Reagents, Indicators and Solutions

USP 36 Reagents / Reagents 1133

Reagents, Indicators andSolutions

This section deals with the reagents and solutions re- Where a particular brand or source of a material or piecequired in conducting the Pharmacopeial and the National of equipment, or the name and address of a manufacturer,Formulary tests and assays. is mentioned, this identification is furnished solely for infor-

As is stated in the General Notices, listing of reagents, in- mational purposes as a matter of convenience, without im-dicators, and solutions in the Pharmacopeia in no way im- plication of approval, endorsement, or certification.plies that they have therapeutic utility; thus, any reference Atomic absorption and flame photometry require the useto the USP in their labeling is to include the term “reagent” of a number of metal-ion standard solutions. While the indi-or “reagent grade.” vidual monographs usually provide directions for prepara-

Reagents required in the tests and assays for the Pharma- tion of these solutions, use of commercially prepared stan-copeial and National Formulary articles are listed in this sec- dardized solutions of the appropriate ions is permissible,tion, generally with specifications appropriate to their in- provided that the analyst confirms the suitability of the solu-tended uses. Exceptions to the latter include those reagents tions and has data to support their use.for which corresponding specifications are presented in the Reagents are substances used either as such or as constit-current edition of Reagent Chemicals, published by the uents of solutions.American Chemical Society, and reagents for which specifi- Indicators are reagents used to determine the specifiedcations could not be drafted in time for inclusion here. endpoint in a chemical reaction, to measure hydrogen-ionThus, where it is directed to “Use ACS reagent grade,” it is concentration (pH), or to indicate that a desired change inintended that a grade meeting the corresponding specifica- pH has been effected. They are listed together with indica-tions of the current edition of ACS Reagent Chemicals shall tor test papers.be used. Where no such specifications exist, and where it is Buffer Solutions are referred to separately.directed to “Use a suitable grade,” the intent is that a suita- Colorimetric Solutions, abbreviated “CS,” are solutionsble reagent grade available commercially shall be used. Oc- used in the preparation of colorimetric standards for com-casionally, additional test(s) augment the designation “suita- parison purposes.ble grade,” as indicated in the text. Listed also are some, Test Solutions, abbreviated “TS,” are solutions of re-but not all, reagents that are required only in determining agents in such solvents and of such definite concentrationsthe quality of other reagents. For those reagents that are as to be suitable for the specified purposes.not listed, satisfactory specifications are available in standard Volumetric Solutions, abbreviated “VS” and known alsoreference works. as Standard Solutions, are solutions of reagents of known

In those instances in which a reagent required in a Phar- concentration intended primarily for use in quantitative de-macopeial or National Formulary test or assay need not be terminations. Concentrations are usually expressed in termsof analytical reagent quality, it suffices to refer to the mono- of normality.graph for that article appearing in this Pharmacopeia or the Water—As elsewhere in the Pharmacopeia, whereNational Formulary or the current edition of the Food “water”, without qualification, is mentioned in the tests forChemicals Codex (FCC). In such cases it is to be understood reagents or in directions for preparing test solutions, etc.,that the specifications are minimum requirements and that Purified Water (USP monograph) is always to be used. Car-any substance meeting more rigid specifications for chemi- bon dioxide-free water is Purified Water that has been boiledcal purity is suitable. vigorously for 5 minutes or more and allowed to cool while

Where the name of a reagent specified in a test or assay is protected from absorption of carbon dioxide from the at-the same as the title of a USP or NF article, and it does not mosphere, or Purified Water that has a resistivity of not lessappear among the following Reagent Specifications, a sub- than 18 Mohm-cm. Deaerated water, for purposes otherstance meeting the requirements of the USP or NF mono- than dissolution and drug release testing, is Purified Watergraph is to be used (e.g., Benzocaine, USP; or Propylparaben, that has been treated to reduce the content of dissolved airNF). However, reference is specifically made, under Reagent by suitable means, such as by boiling vigorously for 5 min-Specifications, to a reagent bearing the name of a USP or NF utes and cooling or by the application of ultrasonic vibra-article: (1) where there are requirements for a reagent in tion. Particle-free water is water that has been passedaddition to the USP or NF monograph requirements (e.g., through a 0.22-µm filter.Sodium Salicylate, USP; or Isopropyl Myristate, NF), (2) where Organic-free water is Purified Water that produces no sig-a source other than the USP or NF monograph is specified nificantly interfering peaks when chromatographed as it is(e.g., Lactose, ACS reagent; or Hydrochloric Acid, ACS rea- indicated in Identification, Control, and Quantification of Re-gent), (3) where complete reagent specifications differ from sidual Solvents under Residual Solvents ⟨467⟩.the USP or NF monograph standards (e.g., Calcium Lactate; Chromatographic Solvents and Carrier Gases—Theor Thymol), or (4) where a standard material is included chromatographic procedures set forth in the Pharmacopeiaamong the reagent specifications (e.g., Calcium Carbonate, may require use of solvents and gases that have been espe-primary standard; or Sodium Carbonate, primary standard). cially purified for such use. The purpose may be (a) to ex-

Reagents and solutions should be preserved in tight con- clude certain impurities that interfere with the proper con-tainers made of resistant glass or other suitable material. duct of the test procedure, or (b) to extend the life of aDirections for storage in light-resistant containers should be column by reducing the build-up of impurities on the col-carefully observed. umn. Where solvents and gases are called for in chromato-

Stoppers and stopcocks brought into contact with sub- graphic procedures, it is the responsibility of the analyst tostances capable of attacking or penetrating their surfaces ensure the suitability of the solvent or gas for the specificmay be given a protective coating of a thin film of a suita- use. Solvents and gases suitable for specific high-pressure orble lubricant unless specifically interdicted. other chromatographic uses are available as specialty prod-

ucts from various reagent supply houses, although there is

1134 Reagents / Reagents USP 36

no assurance that similar products from different suppliers uses of the solvents and gases and not for chromatographicare of equivalent suitability in any given procedure. The rea- uses for which the especially purified specialty products maygent specifications provided herein are for general analytical be required.

ReagentsFor the purposes of the following specifications, these def- Arsenic in Reagents

initions apply: A blank consists of the same quantities of thesame reagents treated in the same manner as the specimen Select reagents for this test for a low arsenic content, sounder test. A control is a blank to which has been added the that a blank test results in either no stain or one that islimiting quantity of the substance being tested for, or is a barely perceptible.specified comparison solution prepared as directed in the APPARATUS—Prepare a generator by fitting a 1-hole rubberparticular test. stopper into a wide-mouth bottle of about 60-mL capacity.The values given in boldface type following chemical sym- Through the perforation insert a vertical exit tube aboutbols and formulas represent, respectively, atomic and molec- 12 cm in total length and 1 cm in diameter along the entireular weights of the substances concerned. upper portion (for about 8 cm) and constricted at its lowerColor and turbidity comparisons are to be made in color- extremity to a tube about 4 cm in length and about 5 mmcomparison tubes that are matched as closely as possible in in diameter. The smaller portion of the tube should extendinternal diameter and in all other respects, as directed for to just slightly below the stopper. Place washed sand or aVisual Comparison under Spectrophotometry and Light-scatter- pledget of purified cotton in the upper portion to abouting ⟨851⟩. Such tubes frequently are called “Nessler tubes.” 3 cm from the top of the tube. Moisten the sand or cottonIn making visual comparisons of the densities of turbid uniformly with lead acetate TS, and remove any excess orfluids, compensate for differences in color, if necessary, by adhering droplets of the latter from the walls of the tube.viewing the turbidity through a column of water, the depth Into the upper end of this tube fit a second glass tubeof which is determined by the volume specified in the indi- 12 cm in length, having an internal diameter of 2.5 tovidual reagent specification. Place the water in color-com- 3 mm, by means of a rubber stopper. Just before runningparison tubes, and hold one of the tubes above the control the test, place a strip of mercuric bromide test paper (seetube and the other below the specimen tube. under Indicator and Test Papers) in this tube, crimping theWhere an expression such as “Retain the filtrate” appears upper end of the strip so that it will remain in positionit is to be understood, unless otherwise indicated, that the about 2 cm above the rubber stopper. Clean and dry thewashings of the residue are not to be added to the filtrate tube thoroughly each time it is used.obtained. In the test heading, Calcium, magnesium, and R2O3

STANDARD ARSENIC SOLUTION—Use Standard Preparation pre-precipitate, the expression R2O3 is intended to indicate thepared as directed under Arsenic ⟨211⟩.residue on ignition from compounds precipitated upon the

TEST PREPARATION—Add 1 mL of sulfuric acid to 5 mL of aaddition of ammonium hydroxide, such as Fe2O3 and Al2O3.solution of the chemical substance (1 in 25), unless anotherquantity is directed in the individual reagent specification.Omit its addition entirely in the case of inorganic acids. Un-GENERAL TESTS FOR REAGENTSless especially directed otherwise, add 10 mL of sulfurousacid. Evaporate the liquid in a small beaker, on a steamThe following general test methods are provided for thebath, until it is free from sulfurous acid and has been re-examination of reagents to determine their compliance withduced to about 2 mL in volume. Dilute with water to 5 mLthe specifications of the individual reagents and are to beto obtain the Test Preparation. Substances subjected to spe-used unless it is otherwise directed in such specifications.cial treatments specified in the individual reagent specifica-tion may be used directly as the Test Preparation.

Boiling or Distilling Range for Reagents [NOTE—Solutions prepared by the dissolving of the chem-ical substances in dilute acids are not considered to have

Use the following procedure for determining the boiling undergone special treatment.]or distilling range of reagents, unless otherwise directed in STANDARD STAIN—Place in the generator bottle 5 mL of po-the individual specifications: tassium iodide TS, 2.0 mL of Standard Arsenic Solution, 5 mL

APPARATUS—Use apparatus similar to that specified for Dis- of acid stannous chloride TS, and 28 mL of water. Add 1.5 gtilling Range—Method I ⟨721⟩, except that the distilling flask of granulated zinc (in No. 20 powder), and immediately in-is to be of 250-mL capacity, to have a short neck, and to be sert the stopper containing the exit tube. Keep the genera-connected to the condenser by means of a three-way con- tor bottle immersed in water at 25° during the period of thenecting tube fitted with standard-taper ground joints. test to moderate the reaction so that the stain will take the

form of a distinctive band to facilitate the comparison ofPROCEDURE—Place the distilling flask in an upright positioncolor intensity. When evolution of hydrogen has continuedin the perforation in the asbestos board, and connect it tofor 1 hour, remove the mercuric bromide test paper forthe condenser.comparison. This stain represents 2 µg of arsenic.Measure 100 mL of the liquid to be tested in a graduated

cylinder, and transfer to the boiling flask together with PROCEDURE—Pipet into the generator bottle 5 mL of potas-some device to prevent bumping. Use the cylinder as the sium iodide TS and 5 mL of the Test Preparation, and addreceiver for the distillate. Insert the thermometer, and heat 5 mL of acid stannous chloride TS. Set the apparatus asideso as to distill at the rate of 3 mL to 5 mL per minute. Make at room temperature for a period of 10 minutes, then adda preliminary trial, if necessary, to determine the adjustment 25 mL of water and 1.5 g of granulated zinc (in No.for the proper rate of heating. Read the thermometer when 20 powder), and proceed as directed under Standard Stain.about 20 drops have distilled and thereafter at volumes of Remove the mercuric bromide test paper, and compare thedistillate of 5, 10, 40, 50, 60, 90, and 95 mL. Continue the stain upon it with the Standard Stain: the stain produced bydistillation until the dry point is reached. the chemical tested does not exceed the standard stain in

The Boiling or Distilling Range is the interval between the length or in intensity of color, indicating not more thantemperatures when 1 mL and 95 mL, respectively, have 10 parts of arsenic per million parts of the substance beingdistilled. tested. Since light, heat, and moisture cause the stain to

USP 36 Reagents / General Tests for Reagents 1135

fade rapidly, place the papers in clean, dry tubes, and make ity are available. The preferred type of flame photometer iscomparisons promptly. one that has a red-sensitive phototube, a multiplier photo-

tube, a monochromator, an adjustable slit-width control, aINTERFERING CHEMICALS—Antimony, if present in the sub-selector switch, and a sensitivity control. Other types ofstance being tested, produces a gray stain. Sulfites, sulfides,photometers may be used, provided the operator hasthiosulfates, and other compounds that liberate hydrogenproved that the instrument will determine accurately thesulfide or sulfur dioxide when treated with sulfuric acid mustamount of impurities permitted in the reagent to be tested.be oxidized by means of nitric acid and then reduced by

The flame photometric procedures depend upon the usemeans of sulfur dioxide as directed under Test Preparationof semi-internal standards, and thus require both a Samplebefore they are placed in the apparatus. Certain sulfur com-Solution and a Control Solution. For the Sample Solution, apounds, as well as phosphine, give a bright yellow band onspecified weight of specimen is dissolved and diluted to athe test paper. If sulfur compounds are present, the lead ace-definite volume. For the Control Solution, the same amounttate-moistened cotton or sand will darken. In that case, re-of specimen is dissolved, the limiting amounts of the sus-peat the operation as directed under Test Preparation upon apected impurities are added, and the solution is then di-fresh portion of the solution being tested and use greaterluted to the same definite volume as the Sample Solution.care in effecting the complete removal of the sulfurous acid.The flame photometer is set as directed in the general pro-In testing hypophosphites, observe special care to oxidizecedures and then adjusted to give an emission reading ascompletely the solution being tested as directed, otherwisenear 100% transmittance as is possible with the Control So-the evolution of phosphine may result in a yellow stainlution at the wavelength specified for the particular impuritywhich may be confused with the orange-yellow color pro-concerned. With the instrument settings left unchanged, theduced by arsine. The stain produced by phosphine may beemission from the Sample Solution is read at the same wave-differentiated from that given by arsine by means of moist-length and at a specified background wavelength. The back-ening it with 6 N ammonium hydroxide. A stain caused byground reading is then used to correct the observed emis-arsine becomes dark when so treated, but a stain producedsion of the Sample Solution for the emission due to theby phosphine does not materially change in color.specimen and the solvent. The specimen being tested con-tains less than the specified limit of impurity if the difference

Chloride in Reagents between the observed background and total emissions forthe Sample Solution is less than the difference between theobserved emissions for the Control Solution and the SampleSTANDARD CHLORIDE SOLUTION—Dissolve 165.0 mg of driedSolution at the wavelength designated for the particularsodium chloride in water to make 1000.0 mL. This solutionimpurity.contains the equivalent of 0.10 mg of chlorine (Cl) in each

mL. CALCIUM IN REAGENTS—PROCEDURE—Neutralize, if alkaline, a solution of the quan- Standard Calcium Solution—Dissolve 250 mg of calcium car-

tity of the reagent indicated in the test in 25 mL of water, bonate in a mixture of 20 mL of water and 5 mL of dilutedor a solution prepared as directed in the test, with nitric hydrochloric acid, and when solution is complete, diluteacid, litmus paper being used as the indicator, and add with water to 1 L. This solution contains 0.10 mg of calcium3 mL more of nitric acid. Filter the solution, if necessary, (Ca) per mL.through a filter paper previously washed with water until Procedure—Use the Sample Solution and the Control Solu-the paper is free from chloride, and add 1 mL of silver ni- tion prepared as directed in the individual test procedure.trate TS. Mix, and allow to stand for 5 minutes protected Set the slit-width control of a suitable flame photometerfrom direct sunlight. Compare the turbidity, if any, with that at 0.03 mm, and set the selector switch at 0.1. Adjust theproduced in a control made with the same quantities of the instrument to give the maximum emission with the Controlsame reagents as in the final test and a volume of Standard Solution at the 422.7-nm calcium line, and record the trans-Chloride Solution equivalent to the quantity of chloride (Cl) mittance. Without changing any of the instrument settings,permitted by the test. Adjust the two solutions with water record the transmittance for the emission of the Sample So-to the same volume before adding the silver nitrate TS, and lution at 422.7 nm. Change the monochromator to thecompare the turbidities. wavelength specified in the individual test procedure, and

In testing barium salts, neutralize, if alkaline, the solution record the background transmittance for the backgroundcontaining the reagent, with nitric acid, and add only emission of the Sample Solution: the difference between the3 drops more of nitric acid. Conduct the remainder of the transmittances for the Sample Solution at 422.7 nm and attest as described previously. the background wavelength is not greater than the differ-

In testing salts giving colored solutions, dissolve 2 g of the ence between transmittances observed at 422.7 nm for thereagent in 25 mL of water, and add 3 mL of nitric acid. Sample Solution and the Control Solution.Filter the solution, if necessary, through a filter paper previ- POTASSIUM IN REAGENTS—ously washed with water, and divide the filtrate into two

Standard Potassium Solution—Dissolve 191 mg of potassiumequal portions. Treat one portion with 1 mL of silver nitratechloride in a few mL of water, and dilute with water to 1 L.TS, allow to stand for 10 minutes, and, if any turbidity isDilute a portion of this solution with water in the ratio of 1produced, filter it through a washed filter paper until clear,to 10 to obtain a concentration of 0.01 mg of potassium (K)and use the filtrate as a blank. Treat the other portion withper mL.1 mL of silver nitrate TS, mix, and allow to stand for 5 min-

Procedure—Use the Sample Solution and the Control Solu-utes protected from direct sunlight. Compare the turbiditytion prepared as directed in the individual test procedure.with that produced in the blank by the addition of a volume[NOTE—In testing calcium salts, use an oxyhydrogenof Standard Chloride Solution equivalent to the quantity ofburner.]chloride (Cl) permitted in the test, both solutions being ad-

Set the slit-width control of a suitable flame photometerjusted with water to the same volume.equipped with a red-sensitive detector at 0.1 mm, unlessotherwise directed, and set the selector switch at 0.1. Adjust

Flame Photometry for Reagents the instrument to give the maximum emission with the Con-trol Solution at the 766.5-nm potassium line, and record the

The use of flame photometric procedures to determine transmittance. Without changing any of the instrument set-traces of calcium, potassium, sodium, and strontium is tings, record the transmittance for the emission of the Sam-called for in some of the reagent specifications. The suitabil- ple Solution at 766.5 nm. Change the monochromator toity of such determinations depends upon the use of ade- 750 nm, and record the background transmittance for thequate apparatus, and several instruments of suitable selectiv- background emission of the Sample Solution: the difference

1136 General Tests for Reagents / Reagents USP 36

between the transmittances for the Sample Solution at 766.5 tube add 10 mL of hydrogen sulfide TS, mix, and comparenm and 750 nm is not greater than the difference between the colors by viewing through the color-comparison tubetransmittances observed at 766.5 nm for the Sample Solution downward against a white surface. The color in the testand the Control Solution. specimen is not darker than that of the control.

If the solution of the reagent is prepared as in (b), use forSODIUM IN REAGENTS—the control 10 mL of the solution, and add to it a volume ofStandard Sodium Solution—Dissolve 254 mg of sodium chlo- Standard Lead Solution equivalent to the amount of lead per-ride in a few mL of water, and dilute with water to 1 L. mitted in 2 g of the reagent. Dilute the remaining 30 mL ofDilute a portion of this solution with water in the ratio of 1 solution (b) with water to 35 mL, and proceed as directed into 10 to obtain a concentration of 0.01 mg of sodium (Na) the preceding paragraph, beginning with “add diluted ace-per mL. tic acid, or ammonia TS,” in the second sentence.

Procedure—Use the Sample Solution and the Control Solu- If the reagent to be tested for heavy metals is a salt of antion prepared as directed in the individual test procedure. aliphatic organic acid, substitute 1 N hydrochloric acid for

Set the slit-width control of a suitable flame photometer the diluted acetic acid specified in the foregoing method.at 0.01 mm, and set the selector switch at 0.1. Adjust theinstrument to give the maximum emission with the ControlSolution at the 589-nm sodium line, and record the trans- Insoluble Matter in Reagentsmittance. Without changing any of the instrument settings,record the transmittance for the emission of the Sample Dissolve the quantity of reagent specified in the test inSolutionat 589 nm. Change the monochromator to 580 nm, 100 mL of water, heat to boiling unless otherwise directed,and record the background transmittance for the back- in a covered beaker, and warm on a steam bath for 1 hour.ground emission of the Sample Solution: the difference be- Filter the hot solution through a tared sintered-glass crucibletween the transmittances for the Sample Solution at 589 and of fine porosity. Wash the beaker and the filter thoroughly580 nm is not greater than the difference between transmit- with hot water, dry at 105°, cool in a desiccator, andtances observed at 589 nm for the Sample Solution and the weigh.Control Solution.

STRONTIUM IN REAGENTS— Loss on Drying for ReagentsStandard Strontium Solution—Dissolve 242 mg of strontiumnitrate in a few mL of water, and dilute with water to 1 L. Determine as directed under Loss on Drying ⟨731⟩.Dilute a portion of this solution with water in the ratio of 1to 10 to obtain a concentration of 0.01 mg of strontium (Sr)per mL. Nitrate in Reagents

Procedure—Use the Sample Solution and the Control Solu-tion prepared as directed in the individual test procedure. STANDARD NITRATE SOLUTION—Dissolve 163 mg of potassium

Set the slit-width control of a suitable flame photometer nitrate in water, add water to make 100 mL, and diluteat 0.03 mm, and set the selector switch at 0.1. Adjust the 10 mL of this solution with water to 1 liter, to obtain ainstrument to give the maximum emission with the Control solution containing the equivalent of 0.01 mg of NO3 perSolution at the 460.7-nm strontium line, and record the mL.transmittance. Without changing any of the instrument set- BRUCINE SULFATE SOLUTION—Dissolve 600 mg of brucine sul-tings, record the transmittance for the emission of the Sam- fate in 600 mL of nitrate-free, dilute sulfuric acid (2 in 3)ple Solution at 460.7 nm. Change the monochromator to that previously has been cooled to room temperature, andthe wavelength specified in the individual test procedure, dilute with the acid to 1 L. [NOTE—Prepare the nitrate-freeand record the background transmittance for the back- sulfuric acid by adding 4 parts of sulfuric acid to 1 part ofground emission of the Sample Solution: the difference be- water, heating the solution to dense fumes of sulfur trioxide,tween the transmittances for the Sample Solution at 460.7 and cooling. Repeat the dilution and heating three or fournm and at the background wavelength is not greater than times.]the difference between transmittances observed at 460.7

SAMPLE SOLUTION—To the weight of sample specified in thenm for the Sample Solution and the Control Solution.individual reagent specification, dissolved in the designatedvolume of water, add Brucine Sulfate Solution to make50 mL.Heavy Metals in Reagents

CONTROL SOLUTION—To a volume of Standard Nitrate Solu-tion equivalent to the weight of nitrate (NO3) specified inSTANDARD LEAD SOLUTION—Use Standard Lead Solution (seethe individual reagent specification, add the weight of sam-Heavy Metals ⟨231⟩). Each mL of this solution contains theple specified in the individual reagent specification and thenequivalent of 0.01 mg of Pb.add Brucine Sulfate Solution to make 50 mL.PROCEDURE—Unless otherwise directed, test for heavy met-

BLANK SOLUTION—Use 50 mL of Brucine Sulfate Solution.als as follows:(a) If the heavy metals limit is 0.0005% (5 ppm), dis- PROCEDURE—Heat the Sample Solution, Control Solution, and

solve 6.0 g of the specimen in water to make 42 mL. Blank Solution in a boiling water bath for 10 minutes, then(b) If the heavy metals limit is 0.001% (10 ppm) or cool rapidly in an ice bath to room temperature. Adjust a

more, or in the event of limited solubility, use 4 g, and dis- suitable spectrophotometer to zero absorbance at 410 nmsolve in water to make 40 mL, warming, if necessary, to aid with the Blank Solution. Determine the absorbance of thesolution. Sample Solution, note the result, and adjust the instrument

For the control, transfer 7 mL of the solution from (a) to a to zero absorbance with the Sample Solution. Determine thecolor-comparison tube, and add a volume of Standard Lead absorbance of the Control Solution: the absorbance readingSolution equivalent to the amount of lead permitted in 4 g for the Sample Solution does not exceed that for the Controlof the reagent. Dilute with water to 35 mL, and add diluted Solution.acetic acid, or ammonia TS, until the pH is about 3.5, deter-mined potentiometrically, then dilute with water to 40 mL,

Nitrogen Compounds in Reagentsand mix. Transfer the remaining 35 mL of the solution from(a) to a color-comparison tube closely matching that usedfor the control, and add diluted acetic acid, or ammonia TS, PROCEDURE—Unless otherwise directed, test for nitrogenuntil the pH is about 3.5, determined potentiometrically, compounds as follows: Dissolve the specified quantity of testthen dilute with water to 40 mL, and mix. Then to each specimen in 60 mL of ammonia-free water in a Kjeldahl flask

USP 36 Reagents / Reagent Specifications 1137

connected through a spray trap to a condenser, the end of PROCEDURE—which dips below the surface of 10 mL of 0.1 N hydrochlo- Method I—Neutralize, if necessary, a solution of the quantityric acid. Add 10 mL of freshly boiled sodium hydroxide solu- of the reagent or residue indicated in the test in 25 mL oftion (1 in 10) and 500 mg of aluminum wire, in small water, or a solution prepared as directed in the test, withpieces, to the Kjeldahl flask, and allow to stand for 1 hour, hydrochloric acid or with ammonia TS, litmus paper beingprotected from loss of, and exposure to, ammonia. Distill used as the indicator, and add 1 mL of 1 N hydrochloric35 mL, and dilute the distillate with water to 50 mL. Add acid. Filter the solution, if necessary, through a filter paper2 mL of freshly boiled sodium hydroxide solution (1 in 10), previously washed with water, and add 2 mL of bariummix, add 2 mL of alkaline mercuric-potassium iodide TS, and chloride TS. Mix, allow to stand for 10 minutes, and com-again mix: the color produced is not darker than that of a pare the turbidity, if any, with that produced in a controlcontrol containing the amount of added N (as ammonium containing the same quantities of the same reagents used inchloride) specified in the individual test procedure. the test and a quantity of Standard Sulfate Solution equiva-

lent to the quantity of sulfate (SO4) permitted in the test.Adjust the two solutions with water to the same volumePhosphate in Reagents before adding the barium chloride TS.

Method II—Heat to boiling the solution, prepared as di-STANDARD PHOSPHATE SOLUTION—Dissolve 143.3 mg of dried rected in the individual test procedure, or the filtrate desig-monobasic potassium phosphate, KH2PO4, in water to make nated in the procedure, and add 5 mL of barium chloride1000.0 mL. This solution contains the equivalent of 0.10 mg TS. Then digest the solution on a steam bath for 2 hours,of phosphate (PO4) in each mL. and allow to stand overnight. If any precipitate is formed,PHOSPHATE REAGENT A—Dissolve 5 g of ammonium molyb- filter the solution through paper, wash the residue with hot

date in 1 N sulfuric acid to make 100 mL. water, and transfer the paper containing the residue to aPHOSPHATE REAGENT B—Dissolve 200 mg of p-methylami- tared crucible. Char the paper, without burning, and ignite

nophenol sulfate in 100 mL of water, and add 20 g of so- the crucible and its contents to constant weight. Perform adium bisulfite. Store this reagent in well-filled, tightly stop- blank determination concurrently with the test specimen de-pered bottles, and use within one month. termination, and subtract the weight of residue obtained

from that obtained in the test specimen determination toPROCEDURE—[NOTE—The tests with the specimen and theobtain the weight of residue attributable to the sulfate con-control are made preferably in matched color-comparisontent of the specimen.tubes.] Dissolve the quantity of the reagent specified in the

test, or the residue obtained after the prescribed treatment,in 20 mL of water, by warming, if necessary, add 2.5 mL of REAGENT SPECIFICATIONSdilute sulfuric acid (1 in 7), and dilute with water to 25 mL.(If preferable, the test specimen or the residue may be dis-

Absolute Ether—See Ethyl Ether, Anhydrous.solved in 25 mL of approximately 0.5 N sulfuric acid.) ThenAbsorbent Cotton—Use Purified Cotton (USP mono-add 1 mL each of Phosphate Reagents A and B, mix, and

graph).allow to stand at room temperature for 2 hours. CompareAcetal, C6H14O2—118.2—Use a suitable grade.any blue color produced with that produced in a controlAcetaldehyde (Ethanal; Acetic Aldehyde), CH3CHO—made with the same quantities of the same reagents as in

44.05 [75-07-0]—Colorless liquid. Miscible with waterthe test with the specimen, and a volume of Standard Phos-and with alcohol. Use ACS reagent grade.phate Solution equivalent to the quantity of phosphate (PO4) Acetanilide (Phenylacetamide; Antifebrin), C8H9NO—designated in the reagent specifications.135.16 [103-84-4]—White, shiny crystals, usually inscales, or a white, crystalline powder. Is stable in air. Freelysoluble in alcohol and in chloroform; soluble in boilingResidue on Ignition in Reagentswater, in ether, and in glycerin; slightly soluble in water.

Melting range ⟨741⟩: between 114° and 116°.PROCEDURE—Unless otherwise directed, determine the resi-due on ignition as follows: Weigh accurately 1 to 2 g of the Reaction—Its saturated solution is neutral to litmus.substance to be tested in a suitable crucible that previously Loss on drying ⟨731⟩—Dry it over sulfuric acid for 2 hours:has been ignited, cooled, and weighed. Ignite the sub- it loses not more than 0.5% of its weight.stance, gently and slowly at first and then at a more rapid Residue on ignition (Reagent test): not more thanrate, until it is thoroughly charred, if organic in nature, or 0.05%.until it is completely volatilized, if inorganic in nature. If the Acetic Acid (6 N Acetic Acid)—Use Acetic Acid (NF mono-use of sulfuric acid is specified, cool the crucible, add the graph) or prepare a suitable dilution of glacial acetic acid inspecified amount of acid, and ignite the crucible gently until such a way as to obtain a final concentration of acetic acidfumes no longer are evolved. Then ignite the crucible at between 36.0% and 37.0%, by weight.800 ± 25°, cool in a suitable desiccator, and weigh. If the Acetic Acid, Diluted (1 N Acetic Acid)—Dilute 60.0 mL ofuse of sulfuric acid is not specified, the crucible need not be glacial acetic acid with water to make 1000 mL.cooled but can be ignited directly at 800 ± 25° once the

Residue on evaporation—Evaporate 50 mL on a steamcharring or volatilization is complete. Continue the ignitionbath, and dry the residue at 105° for 2 hours: the residueuntil constant weight is attained, unless otherwise specified.weighs not more than 1 mg (0.002%).Conduct the ignition in a well-ventilated hood, but pro-

tected from air currents, and at as low a temperature as is Chloride (Reagent test)—Five mL shows not more thanpossible to effect the complete combustion of the carbon. A 0.01 mg of Cl (2 ppm).muffle furnace may be used, if desired, and its use is recom- Sulfate (Reagent test, Method I )—Ten mL shows notmended for the final ignition at 800 ± 25°. more than 0.5 mg of SO4 (50 ppm).

Heavy metals (Reagent test)—Evaporate 20 mL on asteam bath to dryness. Add to the residue 2 mL of the acid,Sulfate in Reagentsdilute with water to 25 mL, and add 10 mL of hydrogensulfide TS: any brown color produced is not darker than that

STANDARD SULFATE SOLUTION—Dissolve 181.4 mg of potas-sium sulfate (dried at 105° for 2 hours) in water to make1000 mL. This solution contains the equivalent of 0.10 mgof sulfate (SO4) per mL.

1138 Reagent Specifications / Reagents USP 36

of a control containing 0.04 mg of added Pb and 2 mL of Melting range ⟨741⟩—When previously dried at 110° in athe diluted acetic acid (2 ppm). capillary tube for 1 hour, it melts between 149° and 152°.

Acetic Acid, Glacial, CH3COOH—60.05 [64-19-7]— Reaction—A solution (1 in 10) is neutral to litmus.Use ACS reagent grade. Residue on ignition (Reagent test): negligible, fromAcetic Anhydride (Acetic Oxide; Acetyl Oxide), 200 mg.(CH3CO)2O—102.09 [108-24-7]—Use ACS reagent

Solubility in alcohol—A solution of 500 mg in 5 mL of al-grade.cohol is complete and colorless.Acetone (Propanone; Dimethylformaldehyde),

Percent of acetyl (CH3CO)—Weigh accurately aboutCH3COCH3—58.08 [67-64-1]—Use ACS reagent grade.400 mg, previously dried at 105° for 3 hours, and dissolve in[NOTE—For UV spectrophotometric determinations, use15 mL of water in a glass-stoppered conical flask. AddACS reagent grade Acetone Suitable for Use in UV40.0 mL of 0.1 N sodium hydroxide VS, and heat on aSpectrophotometry.]steam bath for 30 minutes. Insert the stopper, allow to cool,Acetone, Anhydrous, CH3COCH3—58.08—Use ACS rea-add phenolphthalein TS, and titrate the excess alkali withgent grade Acetone.0.1 N sulfuric acid VS. Determine the exact normality of theAcetone, Neutralized—To a suitable quantity of acetone0.1 N sodium hydroxide by titrating 40.0 mL after it hasadd 2 or 3 drops of phenophthalein TS and a sufficientbeen treated in the same manner as in the test. Each mL ofamount of 0.02 or 0.01 N sodium hydroxide to produce a0.1 N sodium hydroxide is equivalent to 4.305 mg offaint pink color. Prepare neutralized acetone just prior toCH3CO. Between 23.2% and 24.2% is found.use.

Acetonitrile (Methyl Cyanide; Cyanomethane), CH3CN— Percent of chlorine (Cl)—Weigh accurately about 400 mg,41.05 [75-05-8]—Use ACS reagent grade. previously dried at 105° for 3 hours, and dissolve in 50 mL

Acetonitrile, Spectrophotometric—Use ACS reagent of water in a glass-stoppered, 125-mL flask. Add with agita-grade, which meets also the requirements of the following tion 30.0 mL of 0.1 N silver nitrate VS, then add 5 mL oftest. nitric acid and 5 mL of nitrobenzene, shake, add 2 mL of

ferric ammonium sulfate TS, and titrate the excess silver ni-Spectral purity—Measure in a 1-cm cell between 250 nmtrate with 0.1 N ammonium thiocyanate VS: each mL of 0.1and 280 nm, with a suitable spectrophotometer, against airN silver nitrate is equivalent to 3.545 mg of Cl. Betweenas the blank: its absorbance is not more than 0.01.19.3% and 19.8% of Cl is found.Acetophenone (Phenylethanone; Phenyl Methyl Ketone),

3-Acetylthio-2-methylpropanoic Acid, C6H10O3S—CH3COC6H5—120.15 [98-86-2]—Liquid. Slightly soluble162.21—Use a suitable grade.in water, freely soluble in alcohol and in ether.

[NOTE—A suitable grade is available as β-(Acetylmer-Melting range ⟨741⟩: between 19° and 20°.capto)isobutyric Acid, catalog number 39059, from SennRefractive index ⟨831⟩: about 1.534 at 20°. Chemicals AG www.sennchem.com.]

Specific gravity ⟨841⟩: about 1.03. N-Acetyl-L-tyrosine Ethyl Ester, C13H17NO4—251.28—De-p-Acetotoluidide, C9H11NO—149.19 [103-89-9]— termine the suitability of the material as directed in the As-

White to off-white powder. say under Chymotrypsin (USP monograph).Assay—Inject an appropriate volume into a gas chromat- Acrylic Acid (2-Propenoic Acid; Vinylformic Acid),

ograph (see Chromatography ⟨621⟩) equipped with a flame- C3H4O2—72.06 [79-10-7]—Colorless liquid. Miscible withionization detector, helium being used as the carrier gas. water, with alcohol, and with ether.The following conditions have been found suitable: a 0.25- Assay—Inject an appropriate specimen into a gas chro-mm × 30-m capillary column coated with a 1-µm layer of matograph (see Chromatography ⟨621⟩), equipped with aphase G2; the injection port temperature is maintained at flame-ionization detector, helium being used as the carrier230°; the detector temperature is maintained at 300°; and gas. The following conditions have been found suitable: athe column temperature is maintained at 130° and pro- 0.25-mm × 30-m capillary column coated with a 1-µm layergrammed to rise 10° per minute to 280°. The area of the of phase G2; the injection port temperature is maintained atC9H11NO peak is not less than 98.5% of the total peak area. 150°; the detector temperature is maintained at 300°; and

Melting range ⟨741⟩: between 145° and 151°. the column temperature is maintained at 50° and pro-Acetylacetone (2,4-Pentanedione; Diacetylmethane), grammed to rise 10° per minute to 200°. The area of the

C5H8O2—100.12 [123-54-6]—Clear, colorless to slightly C3H4O2 peak is not less than 99% of the total peak area.yellow, flammable liquid. Soluble in water; miscible with al- Refractive index ⟨831⟩: between 1.419° and 1.423° atcohol, with chloroform, with acetone, with ether, and with 20°.glacial acetic acid. Activated Alumina—See Alumina, Activated.

Assay—Not less than 98% of C5H8O2, a suitable gas chro- Activated Charcoal—See Charcoal, Activated.matograph equipped with a flame-ionization detector being Activated Magnesium Silicate—See Magnesium Silicate,used and helium being used as the carrier gas. The follow- Activated.ing conditions have been found suitable: a 3-mm × 1.83-m Adamantane, C10H16—136.23 [281-23-2]stainless steel column containing 10% phase G43 on sup- Melting range ⟨741⟩: between 270° and 271°.port S1A; the injection port and detector temperatures are Adenine Sulfate, (C5H5N5)2 · H2SO4 · 2H2O—404.36—maintained at 250° and 310°, respectively; the column tem- White crystals or crystalline powder. Melts, after drying atperature is programmed to rise 8° per minute, from 50° to 110°, at about 200° with some decomposition. One g dis-220°. solves in about 160 mL of water; less soluble in alcohol. Sol-

Refractive index ⟨831⟩: between 1.4505 and 1.4525, at uble in solutions of sodium hydroxide. It is not precipitated20°. from solution by iodine TS or mercuric-potassium iodide TS,

Acetyl Chloride, CH3COCl—78.50 [75-36-5]—Clear, but a precipitate is produced with trinitrophenol TS.colorless liquid. Is decomposed by water and by alcohol. Residue on ignition (Reagent test): negligible, fromMiscible with benzene and with chloroform. Use ACS rea- 100 mg.gent grade. Water—Dry it at 105° to constant weight: it loses not

Specific gravity ⟨841⟩: about 1.1. more than 10.0% of its weight.Acetylcholine Chloride (Trimethylethanaminium Chloride; Adipic Acid (Hexanedioic Acid; 1,4-Butanedicarboxylic Acid),

Acecoline), [CH3COOCH2CH2N(CH3)3]Cl—181.66 C6H10O4—146.14 [124-04-9]—Colorless to white, crystal-[60-31-1]—White, crystalline powder. Very deliquescent; line powder. Slightly soluble in water and in cyclohexane;very soluble in water; freely soluble in alcohol. soluble in alcohol, in methanol, and in acetone; practically

insoluble in benzene and in petroleum benzin.


Assay—Weigh accurately about 0.3 g, and dissolve in hol, gasoline, isopropanol, terpineol, benzene, castor oil, ac-50 mL of alcohol. Add 25 mL of water, mix, and titrate with etone, nicotine, aniline dyes, ether, cadmium iodide, pyri-0.5 N sodium hydroxide VS to a pH of 9.5. Perform a blank dine bases, sulfuric acid, kerosene, and diethyl phthalate.determination, and make any necessary correction. Each mL Use a suitable grade.of 0.5 N sodium hydroxide is equivalent to 36.54 mg of Alcohol, Diluted—Use Diluted Alcohol (NF monograph).C6H10O4. Not less than 98% is found. Alcohol, Isobutyl—See Isobutyl Alcohol.

Alcohol, Isopropyl—See Isopropyl Alcohol.Melting range ⟨741⟩: between 151° and 155°, but theAlcohol, Methyl—See Methanol.range between beginning and end of melting does not ex-Alcohol, Neutralized—To a suitable quantity of alcoholceed 2°.

add 2 or 3 drops of phenolphthalein TS and just sufficientAgar—Use Agar (NF monograph). When used for bacteri-0.02 N or 0.1 N sodium hydroxide to produce a faint pinkological purposes, it is to be dried to a water content of notcolor. Prepare neutralized alcohol just prior to use.more than 20%.

Alcohol, n-Propyl—See n-Propyl Alcohol.Agarose [9012-36-6]—Polysaccharide consisting of 1,3-Alcohol, Secondary Butyl—See Butyl Alcohol, Secondary.linked β-D-galactopyranose and 1,4-linked 3,6-anhydro-α-L-Alcohol, Tertiary Butyl—See Butyl Alcohol, Tertiary.galactopyranose. Use a suitable grade.Aldehyde Dehydrogenase—A white powder. One mgAir–Helium Certified Standard—A mixture of 1.0% air in

contains not less than 2 enzyme activity units.industrial grade helium. It is available from most suppliers ofspecialty gases. Assay—Transfer about 20 mg, accurately weighed, to a

Albumin Bovine Serum [9048-46-8]—Almost colorless to 200-mL volumetric flask, dissolve in 1 mL of water, dilutefaintly yellow powder. Not less than 95% pure. Solubility, with an ice-cold solution of bovine serum albumin (1 in40 mg in 1 mL of water. Molecular weight is approximately 100) to volume, and mix. Use this solution as the Assay66,000. Use a suitable grade. Store between 2° and 8°. preparation. Dissolve 3.3 g of potassium pyrophosphate,

Alcohol, Ethanol, Ethyl Alcohol, C2H5OH—46.07 15 mg of dithiothreitol, and 40 mg of edetate disodium in[64-17-5]—Use a suitable grade with a content of NLT 70 mL of water, adjust with citric acid monohydrate solution92.3% and NMT 93.8%, by weight, corresponding to NLT (2.1 in 10) to a pH of 9.0 ± 0.1, dilute with water to94.9% and NMT 96% by volume, at 15.56°. 100 mL, and mix to obtain a pH 9.0 buffer. Dissolve an ac-

Alcohol, 70 Percent, 80 Percent, and 90 Percent—Pre- curately weighed quantity of β-nicotinamide adeninepare by mixing alcohol and water in the proportions given, dinucleotide (β-NAD) in water to obtain a β-NAD solutionthe measurements being made at 25°. having a known concentration of about 20 mg per mL. Pi-

pet 0.1 mL of the Assay preparation into a 1-cm spectropho-tometric cell. Pipet 0.1 mL of water into a second 1-cmRelative Proportionsspectrophotometric cell to provide the reagent blank. Add

Volume in 2.5 mL of pH 9.0 buffer, 0.2 mL of β-NAD solution, andmL of 0.1 mL of pyrazole solution (0.68 in 100) to each cell, and

Percent by Alcohol, mix. Stopper the cells, and allow to stand for 2 minutes atVolume of Specific 94.9% v/v, 25 ± 1°. Add 0.01 mL of acetaldehyde solution (0.3 in 100)C2H5OH at Gravity Alcohol, Water, Required to each cell, and mix. Stopper the cells, and determine the

15.56° at 25° mL mL for 100 mL absorbance of the solution obtained from the Assay prepara-70 0.884 38.6 15 73.7 tion at a wavelength of 340 nm, using the solution obtained80 0.857 45.5 9.5 84.3 from the reagent blank as the reference. Calculate the90 0.827 51 3 94.8 change, ∆A, in absorbance per minute for the solution ob-

tained from the Assay preparation, starting at the pointThe proportions of alcohol and water taken to prepare when the absorbance and time relationship becomes linear.

these or any other percentage (v/v) solutions may be deter- One enzyme activity unit is defined as the amount of en-mined as follows. Calculate the amount, in mL, of water to zyme that oxidizes 1 µmol of acetaldehyde per minute whenbe mixed with 100 mL of alcohol taken by the formula: the test is conducted under the conditions described herein.

Calculate the enzyme activity units in each mg of aldehyde[94.9(d/c) − 0.8096]100 dehydrogenase taken by the formula:

in which 94.9 is the percentage (v/v) of C2H5OH in alcohol, [(2.91)(200)/(6.3)(0.1)(1000)](∆A/W)0.8096 is the specific gravity of 94.9% alcohol, d is thespecific gravity, obtained from the Alcoholometric Table (see in which ∆A is as defined above and W is the weight, in g,Reference Tables), of the solution containing c% (v/v) of of aldehyde dehydrogenase taken.C2H5OH, and 100 is the volume, in mL, of alcohol taken. Alkaline Phosphatase Enzyme—See Phosphatase Enzyme,

Alcohol, Absolute, C2H5OH—46.07—Use ACS reagent Alkaline.grade Ethyl Alcohol, Absolute. Alkylphenoxypolyethoxyethanol—A nonionic surfactant.

Alcohol, Aldehyde-free—Dissolve 2.5 g of lead acetate in Use a suitable grade.5 mL of water, add the solution to 1000 mL of alcohol con- [NOTE—A suitable grade is available commercially as “Tri-tained in a glass-stoppered bottle, and mix. Dissolve 5 g of ton X-100” from Sigma-Aldrich, www.sigma-aldrich.com.]potassium hydroxide in 25 mL of warm alcohol, cool the Alpha-Chymotrypsin—25 kDa [9004-07-3]—Use a suit-solution, and add it slowly, without stirring, to the alcohol able salt-free grade for protein sequencing. solution of lead acetate. After 1 hour shake the mixture vig- [NOTE—A suitable grade is available as catalog numberorously, allow it to stand overnight, decant the clear liquid, 4423 from www.sigma-aldrich.com.]and recover the alcohol by distillation. Alpha-Cyclodextrin Hydrate (Alpha-Schardinger Dextrin;

Alcohol, Amyl—See Amyl Alcohol. Cyclohexaamylose), C36H60O30 · xH2O [51211-51-9]—Use aAlcohol, Dehydrated (Absolute Alcohol), C2H5OH— suitable grade with a content of NLT 98%.

46.07—Use ACS reagent grade Ethyl Alcohol, Absolute. [NOTE—A suitable grade is available as catalog numberAlcohol, Dehydrated Isopropyl—See Isopropyl Alcohol, 22729 from www.acros.com.]

Dehydrated. Alpha-(2-(methylamino)ethyl)benzyl alcohol—Use aAlcohol, Denaturated—It is ethyl alcohol to which has suitable grade.

been added some substance or substances which, while al- Alphanaphthol—See 1-Naphthol.lowing the use of the alcohol in most applications, renders Alprenolol Hydrochloride, C15H23NO2 · HCl—285.8it entirely unfit for consumption as a beverage. The most [13707-88-5]—Use a suitable grade.common denaturants used, either alone or in combination, Alum (Ammonium Alum, Aluminum Ammonium Sulfate),are the following: methanol, camphor, aldehol, amyl alco- AlNH4(SO4)2 · 12H2O—453.33 [7784-26-1]—Large, color-


less crystals or crystalline fragments or a white powder. Sol- Nitrogen content (Reagent test)—Determine by theuble in 7 parts of water and in about 0.5 part of boiling Kjeldahl method, using a test specimen previously dried atwater; insoluble in alcohol. Use ACS reagent grade. 105° for 2 hours: between 18.4% and 18.8% of N is found,

Ammonium Alum—See Alum. corresponding to not less than 98.5% of C2H5NO2.Alumina—See Aluminum Oxide, Acid-washed. Insoluble matter (Reagent test): not more than 1 mg,Alumina, Activated (Aluminum Oxide), [1344-28-1]—Use from 10 g (0.01%).

a suitable grade. Residue on ignition (Reagent test): not more than 0.05%.Alumina, Anhydrous (Aluminum Oxide; Alumina speciallyChloride (Reagent test)—One g shows not more thanprepared for use in chromatographic analysis) [1344-28-1]—A

0.1 mg of Cl (0.01%).white or practically white powder, 80- to 200-mesh. It doesSulfate (Reagent test, Method I)—Two g shows not morenot soften, swell, or decompose in water. It is not acid-

than 0.1 mg of SO4 (0.005%).washed. Store it in well-closed containers.Aluminon (Aurin Tricarboxylic Acid, [tri]Ammonium Salt), Heavy metals (Reagent test): 0.001%, 5 mL of 1 N hydro-

C22H23N3O9—473.43 [569-58-4]—Yellowish-brown, glassy chloric acid VS being used to acidify the solution of the testpowder. Freely soluble in water. Use ACS reagent grade. specimen.

Aluminum, Al—At. Wt. 26.98154 [7429-90-5]—Use Iron ⟨241⟩—One g, dissolved in 47 mL of water contain-ACS reagent grade, which also meets the requirements of ing 3 mL of hydrochloric acid, shows not more thanthe following test. 0.01 mg of Fe (0.001%).

Arsenic—Place 750 mg in a generator bottle (see Arsenic 4-Aminoantipyrine, C11H13N3O—203.24 [83-07-8]—in Reagents under General Tests for Reagents), omitting the Light yellow, crystalline powder. A 500-mg portion dissolvespledget of cotton. Add 10 mL of water and 10 mL of so- completely in 30 mL of water and yields a clear solution.dium hydroxide solution (3 in 10), and allow the reaction to Melting range ⟨741⟩: between 108° and 110°.proceed for 30 minutes: not more than a barely perceptible p-Aminobenzoic Acid—See Para-aminobenzoic Acid.stain is produced on the mercuric bromide test paper. 2-Aminobenzonitrile (Anthranilonitrile), C7H6N2—118.14

Aluminum Oxide, Acid-Washed (Alumina specially pre- [1885-29-6]—Use 2-Aminobenzonitrile 98%.pared for use in chromatographic analysis) [1344-28-1]— Melting range ⟨741⟩: between 49° and 52°.White or practically white powder or fine granules. Very hy- 4-Amino-6-chloro-1,3-benzenedisulfonamide,groscopic. Store in tight containers. C6H8ClN3O4S2—285.73 [121-30-2]—White powder. Insol-

pH of Slurry—The pH of a well-mixed slurry of 5 g in uble in water and in chloroform; soluble in ammonia TS.150 mL of ammonia-free and carbon dioxide-free water, af- Residue on ignition (Reagent test): not more than 2 mgter 10 minutes’ standing, is between 3.5 and 4.5. from 2 g (0.1%).

Loss on ignition—Weigh accurately about 1 g, and ignite, Absorbance—A 1 in 200,000 solution in methanol exhib-preferably in a muffle furnace at 800° to 825°, to constant its absorbance maxima at about 223 nm, 265 nm, and 312weight: it loses not more than 5.0% of its weight. nm. Its absorptivity (see Spectrophotometry and Light-Scatter-Silica—Fuse 500 mg with 10 g of potassium bisulfate for ing ⟨851⟩) at 265 nm is about 64.0.

1 hour in a platinum crucible, cool, and dissolve in hot 4-Amino-2-chlorobenzoic Acid, C6H3Cl(NH2)(COOH)—water: not more than a small amount of insoluble matter 171.58 [2457-76-3]—White crystals or white, crystallineremains. powder.

Suitability for chromatographic adsorption—Dissolve 50 mg Melting range ⟨741⟩: between 208° and 212°.of o-nitroaniline in benzene to make 50.0 mL. Dilute 10 mL 2-Amino-5-chlorobenzophenone, C13H10ClNO—231.68of the resulting solution with benzene to 100.0 mL, and mix [719-59-5]—Use USP 2-Amino-5-chlorobenzophenone RS.(Solution A). 7-Aminodesacetoxycephalosporanic Acid, C8H10N2O3S—

Weigh quickly about 2 (±0.005) g of specimen in a glass- 214.2—Light yellow powder.stoppered weighing bottle, and rapidly transfer it to a dry, Ordinary impurities ⟨466⟩—glass-stoppered test tube. Add 20.0 mL of Solution A, insert

Test solution: 1 N ammonium hydroxide.the stopper, shake vigorously for 3 minutes, and allow tosettle. Standard solution: 1 N ammonium hydroxide.

Pipet 10 mL of the clear supernatant into a 100-mL volu- Eluant: 0.5 N sodium chloride.metric flask, dilute with benzene to volume, and mix (Solu- Visualization: 1.tion B). 2-Aminoethyl Diphenylborinate—See DiphenylborinicDetermine the absorbances of Solutions A and B at 395 Acid, Ethanolamine Ester.nm, with a suitable spectrophotometer, using benzene as 1-(2-Aminoethyl)piperazine, C6H15N3—129.20the blank. Calculate the quantity, in mg, adsorbed per g of [140-31-8]—Viscous, colorless liquid.test specimen by the formula:

Assay—Inject an appropriate specimen into a suitable gaschromatograph (see Chromatography ⟨621⟩) equipped with[2(1 − AB/AA)]/Wa flame-ionization detector, helium being used as the carriergas. The following conditions have been found suitable: ain which AA and AB are the absorbances of Solutions A and B,0.25-mm × 30-m capillary column coated with G2. The in-respectively; and W is the weight, in g, of the aluminumjection port temperature is maintained at 280°; the columnoxide. Not less than 0.3 mg of o-nitroaniline is adsorbed fortemperature is maintained at 180° and programmed to riseeach g of the aluminum oxide.10° per minute to 280° and held there for 10 minutes. TheAluminum Potassium Sulfate, AlK(SO4)2 · 12H2O—detector temperature is maintained at 300°. The area of the474.39 [10042-67-1]—Use ACS reagent grade.main peak is not less than 97% of the total peak area.Amaranth, C20H11N2Na3O10S3—604.48 [915-67-3]—A

deep brown or dark reddish-brown fine powder. Use a suita- Refractive index ⟨831⟩: between 1.4978 and 1.5010 atble grade. 20°.

Aminoacetic Acid (Glycine), NH2CH2COOH—75.07[56-40-6]—White, crystalline powder. Very soluble in water;slightly soluble in alcohol.


Aminoguanidine Bicarbonate (Aminoguanidine Hydrogen Sparingly soluble in cold water; freely soluble in hot water,Carbonate), CH6N4 · H2CO3—136.11 [2582-30-1]—White in alcohol, and in ether.powder. Assay—Dissolve about 1.5 g, accurately weighed, in

Assay—Dissolve about 34 mg, accurately weighed, in about 400 mL of water in a 500-mL volumetric flask, dilute50 mL of glacial acetic acid. Titrate with 0.1 N perchloric with water to volume, and mix. Transfer 25.0 mL of thisacid VS, determining the endpoint potentiometrically. Per- solution to an iodine flask, add 50.0 mL of 0.1 N bromineform a blank determination, and make any necessary correc- VS, dilute with 50 mL of water, add 5 mL of hydrochlorictions. Each mL of 0.1 N perchloric acid is equivalent to acid, and immediately insert the stopper in the flask. Shake13.61 mg of CH6N4 · H2CO3. Not less than 98.5% is found. for 1 minute, allow to stand for 2 minutes, and add 5 mL of

potassium iodide TS through the slightly loosened stopper.Melting point ⟨741⟩: about 170°, with decomposition.Shake thoroughly, allow to stand for 5 minutes, remove the2-Aminoheptane (2-Heptylamine; 1-Methylhexylamine),stopper, and rinse it and the neck of the flask with 20 mL ofC7H17N—115.22 [123-82-0]—Use a suitable grade with awater, adding the rinsing to the flask. Titrate the liberatedcontent of not less than 99%.iodine with 0.1 N sodium thiosulfate VS, adding 3 mL ofN-Aminohexamethyleneimine (N-Aminohomopiperidine,starch TS as the endpoint is approached. From the volume1-Aminohomopiperidine), C6H14N2—114.19 [5906-35-4]—of 0.1 N sodium thiosulfate used, calculate the volume, inColorless liquid.mL, of 0.1 N bromine consumed by the test specimen. EachAssay—Inject an appropriate specimen into a suitable gas mL of 0.1 N bromine is equivalent to 1.819 mg of C6H7NO:chromatograph (see Chromatography ⟨621⟩) equipped with not less than 99.5% is found.a flame-ionization detector, helium being used as the carrier

Melting range ⟨741⟩: between 121° and 123°.gas. The following conditions have been found suitable: a0.25-mm × 30-m capillary column coated with G2. The in- Loss on drying ⟨731⟩—Dry it over calcium chloride forjection port temperature is maintained at 180°; the column 4 hours: the loss in weight is negligible.temperature is maintained at 80° and programmed to rise Residue on ignition (Reagent test): negligible, from 2 g.10° per minute to 230° and then maintained at 230° for p-Aminophenol (p-Hydroxyaniline), C6H7NO—109.135 minutes. The detector temperature is maintained at 300°. [123-30-8]—Fine, yellowish, crystalline powder. Slightly sol-The area of the main peak is not less than 95% of the total uble in water and in alcohol. Use a suitable grade with apeak area. content of not less than 99%.

Refractive index ⟨831⟩: between 1.4840 and 1.4860 at 3-Amino-1-propanol, H2N(CH2)3OH—75.1120°. [156-87-6]—Liquid.

4-Amino-3-hydroxy-1-naphthalenesulfonic Acid, Boiling range (Reagent test): between 184° and 188°.C10H9NO4S—239.25 [116-63-2]—Light purple powder. Refractive index ⟨831⟩: between 1.461 and 1.463 at 20°.Use ACS reagent grade. 3-Aminopropionic Acid (β-Alanine), NH2CH2CH2COOH—8-Amino-6-methoxyquinoline (6-Methoxy-8-aminoquin- 89.09 [107-95-9]—Use a suitable grade.oline), C10H10N2O—174.2 [90-52-8]—Use a suitable grade 3-Aminosalicylic Acid, C7H7NO3—153.14 [570-23-0]—with a content of not less than 98.0%. Tan-grey powder. Use a suitable grade with a content of not[NOTE—A suitable grade is available from www.3bmedical- less than 97%.systems.com, catalog number 3B3-002598.] Ammonia Detector Tube—A fuse-sealed glass tube so1,2,4-Aminonaphtholsulfonic Acid, C10H9NO4S— designed that gas may be passed through it and containing239.25—White to slightly brownish pink powder. Sparingly suitable absorbing filters and support media for the indica-soluble in water. tor bromophenol blue.

Sensitiveness—Dissolve 100 mg in 50 mL of freshly pre- Measuring range: 5 to 70 ppm.pared sodium bisulfite solution (1 in 5), warming if neces- [NOTE—Available from Draeger Safety, Inc.,sary to effect solution, and filter. Add 1 mL of the filtrate to www.draeger.com, or from Gastec Corp., www.gastec.co.jp,a solution prepared by adding 2 mL of dilute sulfuric acid (1 distributed in the USA by www.nextteq.com.]in 6) and 1 mL of Phosphate Reagent A (see Reagent test) to Ammonia Solution, Diluted—Use Ammonia TS.20 mL of a 1 in 100 dilution of Standard Phosphate Solution Ammonia Water, 25 Percent [1336-21-6]—Use a suitable(see Reagent test): a distinct blue color develops within grade.5 minutes. Ammonia Water, Stronger (Ammonium Hydroxide)—Solubility in sodium carbonate solution—Dissolve 100 mg [1336-21-6]—Use ACS reagent grade Ammonium Hydrox-

in 3 mL of sodium carbonate TS, and add 17 mL of water: ide.not more than a trace remains undissolved. Ammonium Acetate, NH4C2H3O2—77.08 [631-61-8]—

Residue on ignition (Reagent test)—To 1 g add 0.5 mL of Use ACS reagent grade.sulfuric acid, and ignite at 800 ± 25° to constant weight: the Ammonium Bicarbonate (Ammonium Hydrogenresidue weighs not more than 5 mg (0.5%). Carbonate), NH4HCO3—79.06 [1066-33-7]—Use a suitable

grade with a content of NLT 99.0%.Sulfate (Reagent test, Method I)—Heat 500 mg with aAmmonium Bisulfate (Ammonium Hydrogen Sulfate),mixture of 25 mL of water and 2 drops of hydrochloric acid

NH4HSO4—115.11 [7803-63-6]—White crystals. Freelyon a steam bath for 10 minutes. Cool, dilute with water tosoluble in water; practically insoluble in alcohol, in acetone,200 mL, and filter: 20 mL of the filtrate shows not moreand in pyridine.than 0.25 mg of SO4 (0.5%).

2-Aminophenol (o-Aminophenol; 2-Hydroxyaniline), Assay—Dissolve about 300 mg, accurately weighed, inC6H7NO—109.13 [95-55-6]—Off-white powder. Use a 50 mL of a mixture of water and alcohol (25:25). Titratesuitable grade with a content of not less than 99%. with 0.1 N sodium hydroxide VS, determining the endpoint

m-Aminophenol (3-Amino-1-Hydroxybenzene), C6H7NO— potentiometrically. Perform a blank determination and make109.13 [591-27-5]—Cream-colored to pale yellow flakes. any necessary correction. Each mL of 0.1 N sodium hydrox-


ide is equivalent to 11.51 mg of NH4HSO4. Not less than a stream of carbon dioxide through the solution to remove98% is found. any excess sulfur dioxide, then cool, and titrate with 0.1 N

Ammonium Bromide, NH4Br—97.94 [12124-97-9]— potassium permanganate VS. Each mL of 0.1 N potassiumUse ACS reagent grade. permanganate consumed is equivalent to 11.7 mg of

Ammonium Carbonate (Hartshorn Salt) [506-87-6]—Use NH4VO3. Not less than 98.0% is found.ACS reagent grade. Solubility in ammonium hydroxide—Dissolve 1 g in a mix-

Ammonium Chloride (Salmiac), NH4Cl—53.49 ture of 3 mL of ammonium hydroxide and 50 mL of warm[12125-02-9]—Use ACS reagent grade. water: the solution is clear and colorless.

Ammonium Citrate, Dibasic (Citric Acid Diammonium Carbonate—To 500 mg add 1 mL of water and 2 mL ofSalt), (NH4)2HC6H5O7—226.18 [3012-65-5]—Use ACS re- diluted hydrochloric acid: no effervescence is produced.agent grade.Chloride—Dissolve 250 mg in 40 mL of hot water, addAmmonium Dihydrogen Phosphate—See Ammonium

2 mL of nitric acid, and allow to stand for 1 hour. Filter, andPhosphate, Monobasic.to the filtrate add 0.5 mL of silver nitrate TS: any turbidityAmmonium Fluoride, NH4F—37.04 [12125-01-8]—produced does not exceed that of a blank containingUse ACS reagent grade.0.5 mg of added Cl (0.2%).Ammonium Formate (Formic Acid Ammonium Salt),

Sulfate—Dissolve 500 mg in 50 mL of hot water, and addCH5NO2—63.06 [540-69-2]—Use a suitable grade.2 mL of diluted hydrochloric acid and 1.5 g of hydroxyla-Ammonium Hydroxide (Ammonium Aqueous),mine hydrochloride. Heat at 60° for 3 minutes, filter, cool,[1336-21-6]—Use ACS reagent grade.and add to the filtrate 2 mL of barium chloride TS: no tur-Ammonium Hydroxide, 6 N—Prepare by diluting 400 mLbidity or precipitate is produced within 30 minutes.of Ammonia Water, Stronger (see Reagents section) with

Amyl Acetate (Isoamyl Acetate), CH3CO2C5H11—130.18water to make 1000 mL.[2308-18-1]—Clear, colorless liquid. Slightly soluble inAmmonium Molybdate, (NH4)6Mo7O24 · 4H2O—1235.86water. Miscible with alcohol, with amyl alcohol, with ben-[12054-85-2]—Use ACS reagent grade.zene, and with ether.Ammonium Nitrate, NH4NO3—80.04 [6484-52-2]—

Use ACS reagent grade. Specific gravity ⟨841⟩: about 0.87.Ammonium Oxalate, (NH4)2C2O4 · H2O—142.11 Boiling range (Reagent test, Method I): not less than

[6009-70-7]—Use ACS reagent grade. 90%, between 137° and 142°.Ammonium Persulfate (Ammonium Peroxydisulfate), Solubility in diluted alcohol—A 1.0-mL portion dissolves in(NH4)2S2O8—228.20 [7727-54-0]—Use ACS reagent 20 mL of diluted alcohol to form a clear solution.grade Ammonium Peroxydisulfate.

Acidity—Add 5.0 mL to 40 mL of neutralized alcohol, and,Ammonium Phosphate, Dibasic (Diammonium Hydrogenif the pink color is discharged, titrate with 0.10 N sodiumPhosphate), (NH4)2HPO4—132.06 [7783-28-0]—Use ACShydroxide: not more than 0.20 mL is required to restore thereagent grade.pink color (about 0.02% as CH3COOH).Ammonium Phosphate, Monobasic (Ammonium

Dihydrogen Phosphate), NH4H2PO4—115.03 Water—A 5-mL portion gives a clear solution with 5 mL[7722-76-1]—Use ACS reagent grade. of carbon disulfide.

Ammonium Pyrrolidinedithiocarbamate (1-pyrrolidine- Amyl Alcohol (Isoamyl Alcohol), C5H11OH—88.15carbodithioic acid, ammonium salt), C5H12N2S2—164.29 [598-75-4]—Use ACS reagent grade Isopentyl Alcohol.[5108-96-3]—Use a suitable grade. tert-Amyl Alcohol, C5H12O—88.15 [75-85-4]—Clear,

Ammonium Reineckate (Reinecke Salt), NH4 colorless, flammable, volatile liquid.[Cr(NH3)2(SCN)4] · H2O—354.44 [13573-16-5]—Dark red Specific gravity ⟨841⟩: about 0.81.crystals or red, crystalline powder. Moderately soluble in Boiling range (Reagent test): not less than 95%, be-cold water; more soluble in hot water. Gradually decom- tween 100° and 103°.poses in solution.

Residue on evaporation—Evaporate 50 mL (40 g) on aSensitiveness—Dissolve 50 mg in 10 mL of water. Add steam bath, and dry at 105° for 1 hour: the residue weighs0.2 mL of the solution to 1 mL of a solution of 10 mg of not more than 1.6 mg (0.004%).choline chloride in 20 mL of water, and shake gently: a dis-Acids and esters—Dilute 20 mL with 20 mL of alcohol,tinct precipitate forms within 5 to 10 seconds.

add 5.0 mL of 0.1 N sodium hydroxide VS, and reflux gen-Ammonium Sulfamate, NH4OSO2NH2—114.13tly for 10 minutes. Cool, add 2 drops of phenolphthalein TS,[7773-06-0]—Use ACS reagent grade.and titrate the excess sodium hydroxide with 0.1 N hydro-Ammonium Sulfate, (NH4)2SO4—132.14chloric acid VS: not more than 0.75 mL of the 0.10 N so-[7783-20-2]—Use ACS reagent grade.dium hydroxide is consumed, correction being made for theAmmonium Thiocyanate (Ammonium Rhodanide),amount consumed in a blank (0.06% as amyl acetate).NH4SCN—76.12 [1762-95-4]—Use ACS reagent grade.

Aldehydes—Shake 5 mL with 5 mL of potassium hydrox-Ammonium Vanadate (Ammonium Metavanadate),ide solution (30 in 100) in a glass-stoppered cylinder forNH4VO3—116.98 [7803-55-6]—White, crystalline pow-5 minutes, and allow to separate: no color develops in eitherder. Slightly soluble in cold water; soluble in hot water andlayer.in dilute ammonia TS.

α-Amylase—Use a suitable grade. It can be from vegetalAssay—Weigh accurately about 500 mg, transfer to aor animal or microbiological origin.suitable container, add 30 mL of water and 2 mL of dilute

(E)-Anethole (1-Methoxy-4-(1-propenyl)benzene),sulfuric acid (1 in 4), swirl to dissolve, and pass sulfur diox-C10H12O—148.20 [4180-23-8]—Use a suitable grade ofide gas through the solution until reduction is complete andtransisomer.the solution is bright blue in color. Boil gently while passing


Anhydrous Alumina—See Alumina, Anhydrous. and convert it completely to the chloride form by stirringAnhydrous Barium Chloride—See Barium Chloride, Anhy- with 150 mL of hydrochloric acid (5 in 100) for not less

drous. than 30 minutes. Decant the acid, and wash the resin in theAnhydrous Calcium Chloride—See Calcium Chloride, An- same manner with distilled water until the wash water is

hydrous. neutral to litmus.Anhydrous Cupric Sulfate—See Cupric Sulfate, Anhydrous. Transfer 5 to 7 mL of the regenerated resin to a glassAnhydrous Dibasic Sodium Phosphate—See Sodium filtering crucible, and remove only the excess surface water

Phosphate, Dibasic, Anhydrous. by very careful suction filtration. Transfer the conditioned,Anhydrous Magnesium Perchlorate—See Magnesium dried resin to a tared weighing bottle, and weigh. Dry in a

Perchlorate, Anhydrous. vacuum oven at 100° to 105° and at a pressure of 50 mmAnhydrous Magnesium Sulfate—See Magnesium Sulfate, of mercury for 16 hours. Transfer from the vacuum oven to

Anhydrous. a desiccator, and cool to room temperature. Reweigh. TheAnhydrous Methanol—See Methanol, Anhydrous. loss in weight is between 50% and 65%.Anhydrous Potassium Carbonate—See Potassium Car- Total new volume capacity—Transfer 2.5 to 3 mL of the

bonate, Anhydrous. conditioned, undried (See Moisture content, above) resin toAnhydrous Sodium Acetate—See Sodium Acetate, Anhy- a 5-mL graduated cylinder, and fill it with water. Remove

drous. any air bubbles from the resin bed with a stainless steelAnhydrous Sodium Carbonate—See Sodium Carbonate, wire, and settle the resin to its minimum volume by tapping

Anhydrous. the graduated cylinder. Record the volume of the resin.Anhydrous Sodium Sulfate—See Sodium Sulfate, Anhy- Transfer the resin with 100 mL of water to a 250-mL flask.

drous. Add 2 mL of sulfuric acid, heat to 70° to 80°, and hold atAnhydrous Sodium Sulfite—See Sodium Sulfite, Anhy- that temperature for 5 minutes with occasional stirring (do

drous. not boil). Cool to room temperature, and add 2.5 mL ofAniline, C6H5NH2—93.13 [62-53-3]—Use ACS reagent nitric acid (1 in 2), 2 mL of ferric ammonium sulfate TS, and

grade. 0.20 mL of 0.1 N ammonium thiocyanate. Titrate with 0.1Aniline Blue (Certified Biological Aniline Blue) N silver nitrate VS until the solution turns colorless, and add

[8004-91-9]—A water-soluble dye consisting of a mixture of a measured excess (1 to 5 mL). Heat to boiling to coagulatethe tri-sulfonates of triphenylpararosaniline and of the silver chloride precipitate. Cool to room temperature,diphenylrosaniline. add 10 mL of nitrobenzene, shake vigorously, and titrate the

Aniline Sulfate, C12H14N2 · H2SO4—284.33 excess silver nitrate with 0.1 N ammonium thiocyanate VS.[542-16-5]—Use a suitable grade.

Anion-Exchange Resin, Chloromethylated Polystyrene- (net mL AgNO3 × N)/(mL of resin) = mEq/mLDivinylbenzene—Strongly basic, cross-linked resin contain-ing quaternary ammonium groups. It consists of small, The total exchange capacity of the regenerated, wet resin ismoist, yellow beads having a characteristic amine odor. It is more than 1.0 mEq per mL.available in the chloride form which can be converted to Wet screen analysis—The purpose of this test is to identifythe hydroxide form by regeneration with sodium hydroxide properly the mesh size of the resin. To obtain an accuratesolution (1 in 4). For satisfactory regeneration a contact screen analysis requires special apparatus and technique.time of about 25 minutes is required, after which it must be Add 150 mL of resin to 200 mL of distilled water in anwashed with water until neutral. Suitable for use in column appropriate bottle, and allow it to stand at least 4 hours tochromatography. completely swell the resin.

[NOTE—A suitable resin is “Amberlite IRA-400,” available Transfer by means of a graduated cylinder 100 mL of set-from Sigma-Aldrich, www.sigma-aldrich.com.] tled and completely swollen resin to the top screen of a

Anion-Exchange Resin, Strong, Lightly Cross-Linked, in series (20-, 50-, 100-mesh) of 20.3-cm brass screens. Thor-the Chloride Form—Use a suitable grade. oughly wash the resin on each screen with a stream of dis-

[NOTE—A suitable resin is “AG 1-X4, catalog number tilled water until the resin is completely classified, collecting140-1331,” produced by BioRad Laboratories, www.bio-rad. the wash water in a suitable container. Wash the beads re-com.] maining on the respective screens back into the 100-mL cyl-

Anion-Exchange Resin, Styrene-Divinylbenzene— inder, and record the volume of settled resin on eachStrongly basic, cross-linked resin containing quaternary am- screen: not less than 80% of the resin is between 50- andmonium groups and about 8% of divinylbenzene. It is avail- 100-mesh.able in the chloride form in the 50- to 100-, 100- to 200-, p-Anisaldehyde (4-Methoxybenzaldehyde), C8H8O2—and 200- to 400-mesh sizes. It can be converted to the 136.15 [123-11-5]—Clear, colorless liquid.hydroxide form by regeneration with a sodium hydroxide Boiling temperature: 248°.solution (5 in 100). Insoluble in water, in methanol, and in

Density: between 1.119 and 1.123.acetonitrile. Suitable for use in column chromatography.[NOTE—A suitable resin is Dowex 1X8, produced by Dow Refractive index ⟨831⟩: between 1.5725 and 1.5730 at

Chemical Co. (www.dow.com) and available through 20°.Sigma-Aldrich (www.sigma-aldrich.com).] p-Anisidine, C7H9NO—123.06 [104-94-9]—Brown

Anion-Exchange Resin, 50- to 100-Mesh, Styrene- crystals. Use a suitable grade.Divinylbenzene—Strongly basic, cross-linked resin contain- Anisole, CH3OC6H5—108.14 [100-66-3]—Colorless liq-ing quaternary ammonium groups and about 4% of uid.divinylbenzene. It consists of tan-colored beads that may be Assay—Inject an appropriate specimen (about 0.5 µL)relatively free flowing. It is available in the chloride form into a suitable gas chromatograph (see Chromatographywhich can be converted to the hydroxide form by regenera- ⟨621⟩) equipped with a flame-ionization detector, nitrogention with a sodium hydroxide solution (5 in 100). For satis- being used as the carrier gas. The following conditions havefactory regeneration a contact time of at least 30 minutes is been found suitable: a 30-m capillary column is coated withrequired after which it must be washed free of excess alkali. phase G3; the injection port and detector temperatures areInsoluble in water, in methanol, and in acetonitrile. Suitable maintained at 140° and 300°, respectively; the column tem-for use in column chromatography. perature is maintained at 70° and programmed to rise 10°

[NOTE—A suitable resin is “Dowex 1X4,” available from per minute to 170°. The area of the anisole peak is not lessSigma-Aldrich, www.sigma-aldrich.com.] than 99% of the total peak area.

Moisture content of fully regenerated and expanded resin— Refractive index ⟨831⟩: 1.5160 at 20°.Transfer 10 to 12 mL of the resin (as received) to a flask,


Anthracene, C14H10—178.23 [120-12-7]—White to off- pears the endpoint has been reached. Each mL of 0.1 Nwhite crystals or platelets. Darkens in sunlight. Insoluble in sodium thiosulfate is equivalent to 14.95 mg of SbCl5: notwater; sparingly soluble in alcohol, in benzene, and in chlo- less than 99.0% of SbCl5 is found.roform. Sulfate (Reagent test, Method II)—Dissolve 4.3 mL (10 g)

Melting range ⟨741⟩: between 215° and 218°. in the minimum volume of hydrochloric acid, dilute withAnthrone, C14H10O—194.23 [90-44-8]—Use ACS rea- water to 150 mL, neutralize with ammonium hydroxide, and

gent grade. filter. To the filtrate add 2 mL of hydrochloric acid: the solu-Anti-D Reagent—The reagent can be monoclonal (low tion, 10 mL of barium chloride TS being used, yields not

protein) or polyclonal (high-protein) and must be obtained more than 1.3 mg of residue, correction being made for afrom manufacturers or suppliers licensed by the Center for complete blank test (0.005%).Biologics Evaluation and Research, Food and Drug Adminis- Arsenic—Add 10 mL of a recently prepared solution oftration. The use of reagents from an unlicensed manufac- 20 g of stannous chloride in 30 mL of hydrochloric acid toturer or supplier may invalidate the results. Note that this 100 mg of specimen dissolved in 5 mL of hydrochloric acid.reagent is different from Anti-D (Rho) Reagent. Consult man- Mix, transfer to a color-comparison tube, and allow to standufacturer’s package insert to ensure that the reagent is suita- for 30 minutes. Any color in the solution of the specimenble for the Weak Anti-D test and does not contain other should not be darker than that in a control containingantibodies that will react when antihuman immunoglobulin 0.02 mg of arsenic (As), which has been treated in the sameis added. manner as the test specimen, when viewed downward over

[NOTE—There are many manufacturers and suppliers of a white surface (0.02% of As).these reagents that are licensed by the Center for Biologics Substances not precipitated by hydrogen sulfide (as SO4)—Evaluation and Research, Food and Drug Administration. Dissolve 0.90 mL (2 g) in 5 mL of hydrochloric acid, and di-Some examples of licensed manufacturers or suppliers are lute with 95 mL of water. Precipitate the antimony com-the following: Gamma Biologics, Houston, TX; and Ortho pletely with hydrogen sulfide, allow the precipitate to settle,Diagnostics, Raritan, NJ.] and filter, being careful not to transfer much of the precipi-Anti-D (Rho) Reagent—The reagent can be monoclonal tate to the filter paper. (Retain the precipitate.) To 50 mL ofor polyclonal and must be obtained from manufacturers or the filtrate, add 0.5 mL of sulfuric acid, evaporate in a taredsuppliers licensed by the Center for Biologics Evaluation and porcelain crucible to dryness, and ignite at 800 ± 25° forResearch, Food and Drug Administration for use in 15 minutes. (Retain the residue.) The weight of the ignitedmicroplate tests. The use of reagents from an unlicensed residue should not be more than 0.0010 g greater than themanufacturer or supplier may invalidate the results. Note weight obtained in a complete blank test (0.10%).that this reagent is different from Anti-D Reagent. Consult

Iron ⟨241⟩—To the residue from the test for Substancesmanufacturer’s package insert to ensure that it is Anti-Dnot precipitated by hydrogen sulfide add 2 mL of hydrochloric(Rho) Reagent and not Anti-D Reagent.acid and 5 drops of nitric acid, and evaporate on a steam[NOTE—There are many manufacturers and suppliers ofbath to dryness. Take up the residue in 2 mL of hydrochloricthese reagents that are licensed by the Center for Biologicsacid, and dilute with water to 47 mL: the solution showsEvaluation and Research, Food and Drug Administration.not more than 0.01 mg of Fe (0.001%).Some examples of licensed manufacturers or suppliers are

Other heavy metals (as Pb)—Dissolve the precipitate onthe following: Gamma Biologics, Houston, TX; and Orthothe filter paper from the test for Substances not precipitatedDiagnostics, Raritan, NJ.]by hydrogen sulfide, with 75 mL of a solution containing 6 gAntifoam Reagent—A 10% silicone–glycol emulsion,of sodium sulfide and 4 g of sodium hydroxide dissolved inwhite in appearance. Nonionic but miscible with cool water.and diluted with water to 100 mL. Collect the filtrate in the[NOTE—A suitable grade is available as “Antifoamoriginal flask containing the remainder of the sulfide precipi-Reagent,” catalog number 2210, from Dow Corning Corpo-tate. Warm the solution to dissolve the soluble sulfides, andration, www.dowcorning.com.]allow the insoluble sulfides to settle. Filter, wash thoroughlyAntihuman Globulin Reagent—The reagent can be poly-with hydrogen sulfide TS, and dissolve any precipitate re-specific or anti-immunoglobulin (Anti-IgG) and must be ob-maining on the filter paper with 10 mL of hot diluted hy-tained from manufacturers or suppliers licensed by thedrochloric acid. Dilute the filtrate with water to 50 mL. Neu-Center for Biologics Evaluation and Research, Food andtralize a 25-mL portion of this solution with 1 N sodiumDrug Administration. The use of reagents from an unli-hydroxide, and add 1 mL of 1 N acetic acid and 10 mL ofcensed manufacturer or supplier may invalidate the results.hydrogen sulfide TS. Any brown color should not exceed[NOTE—There are many manufacturers and suppliers ofthat produced by 0.05 mg of lead ion in an equal volume ofthese reagents that are licensed by the Center for Biologicssolution containing 1 mL of 1 N acetic acid and 10 mL ofEvaluation and Research, Food and Drug Administration.hydrogen sulfide TS (0.005%).Some examples of licensed manufacturers or suppliers are

Antimony Trichloride (Antimonous Chloride), SbCl3—the following: Gamma Biologics, Houston, TX; and Ortho228.12 [10025-91-9]—Use ACS reagent grade.Diagnostics, Raritan, NJ.]

Antithrombin III—Antithrombin III human (heparinAntimony Pentachloride, SbCl5—299.02cofactor, factor IIa inhibitor, and factor Xa inhibitor) is a ser-[7647-18-9]—Clear, reddish-yellow, oily, hygroscopic, caus-ine protease inhibitor. It is a glycoprotein having a molecu-tic liquid. Fumes in moist air and solidifies by absorption oflar weight of 58,000 Da.one molecule of water. Is decomposed by water; soluble in

One Antithrombin III Unit is the amount found in 1 mL ofdilute hydrochloric acid and in chloroform. Boils at aboutnormal human plasma. The potency of antithrombin III is92° at a pressure of 30 mm of mercury and has a specificnot less than 4.0 Antithrombin III Units per mg of proteingravity of about 2.34 at 25°.when tested in the presence of heparin. It exhibits 90%[CAUTION—Antimony pentachloride causes severe burns, andhomogeneity when tested by SDS-PAGE.the vapor is hazardous.]

Antithrombin III for test or assay purposes contains noAssay (SbCl5)—Accurately weigh a glass-stoppered,detectable heparin. Test as follows. To a solution containing125-mL flask, quickly introduce about 0.3 mL of the test1 Antithrombin III Unit per mL, add 1 µL of toluidine bluespecimen, and reweigh. Dissolve with 20 mL of diluted hy-solution. In the presence of heparin, the color changes fromdrochloric acid (1 in 5), and add 10 mL of potassium iodideblue to purple.solution (1 in 10) and 1 mL of carbon disulfide. Titrate the

Aprobarbital, C10H14N2O3—210.23 [77-02-1]—Fine,liberated iodine with 0.1 N sodium thiosulfate VS. Thewhite crystalline powder. Slightly soluble in cold water; solu-brown color will gradually disappear from the solution, andble in alcohol, in chloroform, and in ether.the last traces of free iodine will be collected in the carbon

disulfide, giving a pink color. When this pink color disap-


Assay—Dissolve about 200 mg, previously dried at 105° Barium Chloride Dihydrate—Use Barium Chloride.for 2 hours and accurately weighed, in 20 mL of dimethyl- Barium Hydroxide, Ba(OH)2 · 8H2O—315.46formamide in a 100-mL conical flask. Add 4 drops of thymol [12230-71-6]—Use ACS reagent grade.blue solution (1 in 200 in methanol), and titrate with 0.1 N Barium Nitrate, Ba(NO3)2—261.34 [10022-31-8]—Uselithium methoxide VS using a 10-mL buret, a magnetic stir- ACS reagent grade.rer, and a cover for the flask to protect against atmospheric Basic Fuchsin—See Fuchsin, Basic.carbon dioxide. Perform a blank determination, and make Beclomethasone C22H29ClO5—408.92 [4419-39-0]—any necessary correction. Each mL of 0.1 N lithium methox- Use a suitable grade with a content of not less than 99%.ide is equivalent to 21.02 mg of C10H14N2O3. Between Beef Extract—A concentrate from beef broth obtained by98.5% and 101.0% of C10H14N2O3 is found. extraction from fresh, sound, lean beef by means of cooking

with water and evaporating the broth at a low temperature,Melting range ⟨741⟩: between 140° and 143°.usually in vacuum, until a thick, pasty residue results. Yel-Arsenazo III Acid, C22H18As2N4O14S2—776.38lowish brown to dark brown, slightly acid, pasty mass hav-[1668-00-4]—Brown powder. Stable in air. Store at rooming an agreeable meat-like odor. Store it in tight, light-resis-temperature in a dry area.tant containers.Melting temperature ⟨741⟩: greater than 320°. For the following tests, prepare a test solution by dissolv-Arsenic Trioxide, As2O3—197.84 [1327-53-3]—Use ing 25 g in water to make 250 mL of a practically clear andACS reagent grade. practically sediment-free solution.[NOTE—Arsenic Trioxide of a quality suitable as a primary

Assay for nitrogen content of alcohol-soluble substances—standard is available from the National Institute of StandardsPlace a portion of the alcohol filtrate and washings remain-and Technology, Office of Standard Reference Materials,ing from the test for Alcohol-insoluble substances, corre-www.nist.gov, as standard sample No. 83.]sponding to 1 g of the alcohol-soluble solids, in a 500-mLL-Asparagine (L-2-Aminosuccinamic Acid),Kjeldahl flask. Add about 10 g of powdered potassium sul-COOHCH(NH2)CH2CONH2 · H2O—150.13 [70-47-3]—fate and 20 mL of sulfuric acid. Heat the mixture at a lowColorless crystals. One g dissolves in 50 mL of water; solubletemperature until frothing ceases, then raise the tempera-in acids and in alkalies; insoluble in alcohol and in ether. Itsture and boil until the mixture acquires a pale yellow colorneutral or alkaline solutions are levorotatory; its acid solu-or becomes practically colorless. Cool the flask, add abouttions are dextrorotatory.250 mL of water, and cautiously add sodium hydroxide so-Specific rotation ⟨781⟩: between +31° and +33°, deter- lution (3 in 10) until the contents are alkaline, then addmined in a solution in diluted hydrochloric acid containing 5 mL more. Connect the flask at once by means of a spraythe equivalent of 5 g (on the anhydrous basis, as deter- trap to a condenser, the lower outlet tube of which dipsmined by drying at 105° for 5 hours) in each 100 mL. beneath the surface of 50.0 mL of 0.1 N sulfuric acid VS

Residue on ignition (Reagent test): not more than 0.1%. contained in a receiving flask. Distill the mixture until aboutChloride (Reagent test)—One g shows not more than 100 mL of distillate has been collected in the acid. Add

0.03 mg of Cl (0.003%). methyl red TS, and titrate the excess acid with 0.1 N so-dium hydroxide VS. Each mL of 0.1 N sulfuric acid is equiva-Sulfate (Reagent test, Method I )—One g shows not morelent to 1.401 mg of N. Not less than 60 mg of nitrogen isthan 0.05 mg of SO4 (0.005%).found.Heavy metals (Reagent test): 0.002%.

Assay for nitrogen as ammonia—To 100 mL of test solu-Nitrogen content, Method II ⟨461⟩: between 18.4% andtion, contained in a 500-mL Kjeldahl flask, add 5 g of bar-18.8% of N is found.ium carbonate and 100 mL of water, and by means of aL-Aspartic Acid, C4H7NO4—133.1 [56-84-8]—White tospray trap, connect the flask to a condenser, the lower out-off-white powder. Use a suitable grade.let tube of which dips beneath the surface of 50.0 mL of 0.1Azure A, C14H14ClN3S—291.80 [531-53-3]—Use a suit-N sulfuric acid VS contained in a receiving flask. Distill theable grade.mixture until about 100 mL of distillate has been collected,Bacterial Alkaline Protease Preparation—Use a suitableadd methyl red TS, and titrate the excess acid with 0.1 Ngrade.sodium hydroxide VS. Each mL of 0.1 N sulfuric acid is[NOTE—A suitable grade is commercially available asequivalent to 1.703 mg of NH3. The amount of ammonia“Protex 6L” from Genencor, www.genencor.com, or asfound does not exceed 0.35% of the total solids in the por-“Optimase Enzyme” from Solvay Enzymes Inc., www.tion of test solution taken.solvaypharmaceuticals.com.]

Total solids—Distribute 10 mL of test solution over clean,Barbital Sodium, C8H11N2NaO3—206.2 [144-02-5]—dry sand or asbestos, tared in a porcelain dish, and dry atWhite, crystalline powder or colorless crystals. Freely soluble105° for 16 hours: the residue weighs not less than 750 mgin water; slightly soluble in alcohol. Use a suitable reagent(75%).grade.

Barbituric Acid, C4H4N2O3—128.09 [65-52-7]— Residue on ignition—Incinerate the residue obtained inFaintly beige powder. Soluble in water, in alcohol, in chloro- the test for Total solids by heating the dish to a dull-redform, and in ether. Melts with decomposition at 251.6°. Use heat: the residue does not exceed 30% of the total solids.a suitable grade. Chlorides calculated as sodium chloride—Dissolve the ash

Barium Acetate, C4H6BaO4—255.43 [543-80-6]—Use obtained in the test for Residue on ignition in about 50 mL ofACS reagent grade. water, and carefully transfer to a 100-mL volumetric flask.

Barium Chloride, BaCl2 · 2H2O—244.26 Add to the solution a few drops of nitric acid and 10.0 mL[10326-27-9]—Use ACS reagent grade. of 0.1 N silver nitrate VS. Add water to volume, and mix.

Barium Chloride, Anhydrous, BaCl2—208.23 Filter into a dry flask through a dry filter, rejecting the first[10361-37-2]—This may be made by drying barium chloride 10 mL of the filtrate. To 50.0 mL of the subsequent filtratein thin layers at 125° until the loss in weight between two add 1 mL of ferric ammonium sulfate TS, and titrate withsuccessive, 3-hour drying periods does not exceed 1%. 0.1 N ammonium thiocyanate VS. Each mL of 0.1 N silver

nitrate is equivalent to 5.844 mg of NaCl. The weight ofchlorides calculated as sodium chloride obtained, when mul-tiplied by 2, does not exceed 6% of the total solids.

Alcohol-insoluble substances—Transfer 25 mL of test solu-tion to a 100-mL conical flask, add 50 mL of alcohol, andshake thoroughly. Collect the precipitate on a counterpoisedfilter, wash it three times with a mixture of 2 volumes of


alcohol and 1 volume of water, and dry at 105° for 2 hours: and Technology, Office of Standard Reference Materials,the weight of the precipitate, representing the alcohol-insol- www.nist.gov, as standard sample No. 350.]uble solids, does not exceed 10% of the total solids in the Benzophenone, (C6H5)2CO—182.22 [119-61-9]—portion of test solutiontaken. White, crystalline powder.

Nitrate—Boil 10 mL of test solution for 1 minute with Melting range ⟨741⟩: between 47° and 49°.1.5 g of activated charcoal, add water to replace that lost by p-Benzoquinone (Quinone), C6H4O2—108.09evaporation, filter, and add 1 drop of the filtrate to 3 drops [106-51-4]—Dark yellow powder having a green cast.of a 1 in 100 solution of diphenylamine in sulfuric acid: no Slightly soluble in water; soluble in alcohol, in ether, and inblue color is produced. fixed alkali solutions. May darken on standing. Darkened

Benzaldehyde, C7H6O—106.12 [100-52-7]—Color- material may be purified by sublimation in vacuum.less, strongly refractive liquid. Soluble in water; miscible Melting range ⟨741⟩: between 113° and 115°.with alcohol, with ether, and with fixed and volatile oils. Benzoyl Chloride, C6H5COCl—140.57 [98-88-4]—Use

Assay—Pipet about 1 mL into a tared, glass-stoppered ACS reagent grade.weighing bottle, and weigh accurately. Loosen the stopper, N-Benzoyl-L-arginine Ethyl Ester Hydrochloride, and transfer both the weighing bottle and its contents to a C15H22N4O3 · HCl—342.82—Determine suitability for use as a250-mL conical flask containing 25 mL of a hydro-alcoholic substrate as directed under Crystallized Trypsin (USP mono-solution of hydroxylamine hydrochloride (prepared by dis- graph).solving 34.7 g of hydroxylamine hydrochloride in 160 mL of 3-Benzoylbenzoic Acid, C14H10O3—226.23water, then adding alcohol to make 1000 mL, and neutraliz- [579-18-0]—White to off-white powder.ing to bromophenol blue by the addition of sodium hydrox- Assay—Prepare a mixture of 1% trifluoroacetic acid inide TS). Using a graduated cylinder to measure the volume, water and 1% trifluoroacetic acid in acetonitrile (55:45) forrinse the sides of the flask with an additional 50 mL of this the mobile phase. Inject about 20 µL into a suitable liquidreagent solution. Allow the solution to stand for 10 minutes, chromatograph (see Chromatography ⟨621⟩) equipped withadd 1 mL of bromophenol blue TS, and titrate the liberated a 230-nm detector and a 4.6-mm × 15-cm column thathydrochloric acid with 1 N sodium hydroxide VS. Perform a contains packing L1. The flow rate is about 1.5 mL per min-blank determination with the same quantities of the same ute. The area of the C14H10O3 peak is not less than 98.5% ofreagents, and make any necessary correction. Each mL of the total peak area.1 N sodium hydroxide consumed is equivalent to 106.1 mg Benzoylformic Acid (Phenylglyoxylic Acid), of C7H6O. Not less than 98% is found. C6H5COCO2H—150.14 [611-73-4]—Powder. Soluble in

Specific gravity ⟨841⟩: between 1.041 and 1.046. methanol.Refractive index ⟨831⟩: between 1.5440 and 1.5465 at Melting range ⟨741⟩: between 62° and 67°.

20°. Benzphetamine Hydrochloride, C17H21N · HCl—275.82[5411-22-3]—White to off-white, crystalline powder. FreelyHydrocyanic acid—Shake 0.5 mL with 5 mL of water, addsoluble in water, in alcohol, and in chloroform; slightly solu-0.5 mL of sodium hydroxide TS and 0.1 mL of ferrous sul-ble in ether.fate TS, and warm the mixture gently. Add a slight excess of

hydrochloric acid: no greenish-blue color or blue precipitate Assay—Dissolve about 500 mg, accurately weighed, in ais observed within 15 minutes. mixture of 50 mL of glacial acetic acid and 10 mL of mercu-

Benzalkonium Chloride—Use Benzalkonium Chloride (NF ric acetate TS, add 1 drop of crystal violet TS, and titratemonograph). with 0.1 N perchloric acid VS to a blue-green endpoint.

Benzamidine Hydrochloride Hydrate (Benzenecarbox- Perform a blank determination, and make any necessaryimidamide Monohydrochloride, Hydrate), C7H8N2 · HCl · correction. Each mL of 0.1 N perchloric acid is equivalent toxH2O—156.6 [206752-36-5]—White to off-white powder. 27.58 mg of C17H21N · HCl. Between 98.0% and 101.0%,Use a suitable grade. calculated on the dried basis, is found.

[NOTE—A suitable grade is available from Sigma-Aldrich, Melting range ⟨741⟩: between 152° and 158°.www.sigma-aldrich.com.] Specific rotation ⟨781⟩: between +22° and +26°, deter-Benzanilide, C13H11NO—197.23 [93-98-1]—Off-white, mined in a solution containing 200 mg in 10 mL, the speci-light gray to grayish-green powder. Insoluble in water; spar- men having been previously dried in vacuum at 60° foringly soluble in alcohol; slightly soluble in ether. 3 hours.

Melting range ⟨741⟩: between 162° and 165°. Loss on drying ⟨731⟩—Dry it in vacuum at 60° forSolubility in acetone—A 1.0-g portion dissolves completely 3 hours: it loses not more than 1% of its weight.

in 50 mL of acetone to yield a clear solution. Residue on ignition ⟨281⟩: not more than 0.2%.Benzene, C6H6—78.11 [71-43-2]—Use ACS reagent 2-Benzylaminopyridine, C12H12N2—184.24grade. [6935-27-9]—Use a suitable grade.Benzenesulfonamide, C6H5SO2NH2—157.19 1-Benzylimidazole, C10H10N2—158.20 [4238-71-5]—[98-10-2]—White to pale beige crystals. White crystals.Melting range ⟨741⟩: between 150° and 153°. Assay—Transfer about 40 mg, accurately weighed, to aBenzenesulfonyl Chloride, C6H5SO2Cl—176.62 100-mL beaker. Dissolve in 50 mL of glacial acetic acid. Ti-[98-09-9]—Colorless, oily liquid. Insoluble in cold water; sol- trate with 0.1 N perchloric acid VS, determining theuble in alcohol and in ether. Solidifies at 0°. endpoint potentiometrically using a combination calomel-Melting range ⟨741⟩: between 14° and 17°. platinum electrode. Perform a blank determination andBoiling range (Reagent test): between 251° and 252°. make any necessary correction. Each mL of 0.1 N perchloric

Benzhydrol (α-Phenylbenzenemethanol), C13H12O—184.23 acid is equivalent to 15.82 mg of C10H10N2. Not less than[91-01-0]—White to pale yellow crystals. Very slightly solu- 99% is found.ble in water; soluble in alcohol, in ether, and in chloroform. Benzyltrimethylammonium Chloride,

C6H5CH2N(CH3)3Cl—185.69 [56-93-9]—Available as aMelting range ⟨741⟩: between 65° and 67°, but the60% aqueous solution. Is clear and is colorless or not morerange between beginning and end of melting does not ex-than slightly yellow.ceed 2°.

Benzoic Acid, C6H5COOH—122.12 [65-85-0]—Use Assay—Pipet 2 mL into a 50-mL volumetric flask, and addACS reagent grade. water to volume. Pipet 20 mL of the solution into a 125-mL

[NOTE—Benzoic Acid of a quality suitable as a primary conical flask, add about 30 mL of water, then add 0.25 mLstandard is available from the National Institute of Standards of dichlorofluorescein TS, and titrate with 0.1 N silver nitrate


VS. Each mL of 0.1 N silver nitrate is equivalent to 18.57 mg Biphenyl, C12H10—154.21 [92-52-4]—Colorless toof C6H5CH2N(CH3)3Cl. Between 59.5% and 60.5% is found. white crystals or crystalline powder. Insoluble in water; solu-

Beta-lactamase—Beta-lactamase is an enzyme produced ble in alcohol and in ether. Boils at about 254°.by a variety of bacteria, but is usually obtained from culture Melting range ⟨741⟩: between 68° and 72°.filtrates of a strain of Bacillus cereus. It has the specific prop- 2,2′-Bipyridine (α,α′-Dipyridyl), C10H8N2—156.18erty of inactivating penicillins and cephalosporins by split- [366-18-7]—White or pink, crystalline powder. Soluble inting the bond linking the nitrogen of the thiazolidine to the water and in alcohol. Melts at about 69°, and boils at aboutadjacent carbonyl carbon. 272°.

It occurs in the form of small, brown, easily pulverizable Sensitiveness—Prepare the following solutions: (A)—Dis-pieces or granules. Freely soluble in water, forming a slightly solve 350 mg of ferrous ammonium sulfate in 50 mL ofopalescent solution that is practically neutral to litmus pa- water containing 1 mL of sulfuric acid, and add 500 mg ofper. Is precipitated from its water solutions by acetone, by hydrazine sulfate, then add water to make 500 mL. For use,alcohol, and by dioxane, and is inactivated by contact with dilute this solution with water in the ratio of 1 in 100 mL.these solvents. Is rapidly inactivated by ethyl acetate and is (B)—Dissolve 8.3 g of sodium acetate and 12 mL of glacialirreversibly destroyed at a temperature of about 80°. acetic acid in water to make 100 mL. Add 1 mL of a solutionBeta-lactamase is assayed by a procedure depending upon of the specimen (1 in 1000) to a mixture of 10 mL of watera determination of the amount of penicillin G potassium or and 1 mL of each of solutions A and B: a pink color resultspenicillin G sodium destroyed at a pH of 7.0 in a solution of immediately.such concentration that the inactivation proceeds as a zero-Solubility—A 100-mg portion dissolves completely inorder reaction.

10 mL of water.Betanaphthol—See 2-Naphthol.Residue on ignition (Reagent test): not more than 0.2%.Bibenzyl (Dibenzyl), C14H14—182.26 [103-29-7]—Col-

4,4′-Bis(4-amino-1-naphthylazo)-2,2′-stilbenedisulfonicorless crystals. Freely soluble in chloroform and in ether;Acid, C34H26N6O6S2—678.74 [5463-64-9]—Use a suitablesparingly soluble in alcohol; practically insoluble in water.grade.Melting range ⟨741⟩: between 53° and 55°.

[NOTE—A suitable grade is available from TCI America,Bile Salts—A concentrate of beef bile, the principal con-www.tciamerica.com.]stituent of which is sodium desoxycholate, determined as

Bis(2-ethylhexyl) Maleate, C20H36O4—340.50cholic acid. Soluble in water and in alcohol; the solutions[142-16-5]—Colorless to pale yellow, clear liquid. Misciblefoam strongly when shaken.with acetone and with alcohol. Specific gravity about 0.945.Insoluble substances—Dissolve 5 g in 100 mL of dilute al-

Assay—Place about 2.5 g, accurately weighed, in acohol (84 in 100), warming if necessary to aid solution. Fil-250-mL flask, add 50.0 mL of 0.5 N alcoholic potassium hy-ter within 15 minutes through a tared filter, and wash withdroxide VS, and reflux for 45 minutes. Cool, add 0.5 mL ofsmall portions of the dilute alcohol until the last washing isphenolphthalein TS, and titrate the excess alkali with 0.5 Ncolorless or practically so, then dry the residue at 105° forhydrochloric acid VS. Perform a blank determination at the1 hour, and weigh: the weight of the residue does not ex-same time, using the same amount of 0.5 N alcoholic po-ceed 0.1%.tassium hydroxide (see Residual Titrations under TitrimetryAssay— ⟨541⟩). The difference, in mL, between the volumes of 0.5 N

STANDARD CHOLIC ACID SOLUTION—Dissolve 50.0 mg of cholic hydrochloric acid consumed in the test titration and blankacid, accurately weighed, in dilute acetic acid (6 in 10) to titration, multiplied by 85.1, represents the quantity, in mg,make 100 mL, and mix. Store in a refrigerator. of bis(2-ethylhexyl) maleate in the portion taken. Not less

PROCEDURE—Dissolve 1.0 g, accurately weighed, in 50 mL than 97% is found.of dilute acetic acid (6 in 10). Filter the solution, if neces- Bis(2-ethylhexyl) Phthalate, C6H4-1,2-sary, into a 100-mL volumetric flask, wash the original con- [COOCH2(C2H5)CH(CH2)3CH3]2—390.56 [117-81-7]—Col-tainer and the filter with small portions of dilute acetic acid orless to light yellow liquid.(6 in 10), add the same acetic acid to volume, and mix. Refractive index ⟨831⟩: between 1.4855 and 1.4875, atDilute 10 mL of this solution, accurately measured, with di- 20°.lute acetic acid (6 in 10) to make 100 mL, and mix. Bis(2-ethylhexyl) Sebacate (Dioctyl Sebacate),

Pipet 1 mL each of the Standard Cholic Acid Solution and C8H17OOC(CH2)8COOC8H17—426.67 [122-62-3]—Palethe solution of the Bile Salts into two matched test tubes. straw-colored liquid. Insoluble in water. Refractive indexTo each tube add 1 mL, accurately measured, of freshly pre- about 1.448. Suitable for use in gas chromatography.pared furfural solution (1 in 100), immediately place the Specific gravity, 20°/20°⟨841⟩: between 0.913 andtubes in an ice-bath for 5 minutes, then add to each tube 0.917.13 mL, accurately measured, of dilute sulfuric acid, made by

Boiling range: between 243° and 248° at 5 mm of mer-cautiously mixing 50 mL of sulfuric acid with 65 mL ofcury.water. Mix the contents of the tubes, and place them in a

[NOTE—A suitable grade is “Dioctyl Sebacate,” availablewater bath maintained at a temperature of 70° for 10 min-from Sigma-Aldrich, www.sigma-aldrich.com.]utes. Immediately transfer the tubes to an ice-bath for

Bis(2-ethylhexyl)phosphoric Acid [Bis(2-ethylhex-2 minutes, then determine the absorbance of each solutionyl)Phosphate], [CH3(CH2)3CH(C2H5)CH2]2HPO4—322.42at the wavelength of maximum absorbance at about 670[298-07-7]—Light yellow, viscous liquid. Insoluble in water;nm, with a suitable spectrophotometer. Calculate the quan-freely soluble in chloroform and in ethyl acetate. Refractivetity, in mg, of cholic acid (C24H40O5) in the weight of theindex: about 1.443. Specific gravity: about 0.997.Bile Salts taken by the formula:

Assay—Dissolve about 250 mg, accurately weighed, in500(AU/AS) 50 mL of dimethylformamide, add 3 drops of a 1 in 100

solution of thymol blue TS in dimethylformamide, and ti-in which AU and AS are the absorbances of the solutions trate with 0.1 N sodium methoxide VS to a blue endpoint.from the Bile Salts and the Standard Cholic Acid Solution, Perform a blank determination, and make any necessaryrespectively. Not less than 45% of cholic acid is found. correction. Each mL of 0.1 N sodium methoxide is equiva-

lent to 32.24 mg of (C8H17)2HPO4. Between 95% and 105%is found.


Solubility—One volume dissolves in 9 volumes of chloro- [NOTE—There are many manufacturers and suppliers ofform to yield a clear solution, and 1 volume dissolves in 9 these reagents that are licensed by the Center for Biologicsvolumes of ethyl acetate to yield a clear solution. Evaluation and Research Food and Drug Administration.

Some examples of licensed manufacturers or suppliers areColor—A 1 in 100 solution in chloroform exhibits an ab-the following: Gamma Biologics, Houston, TX; and Orthosorptivity of not more than 0.03 at 420 nm.Diagnostics, Raritan, NJ.]Bis(4-sulfobutyl) Ether Disodium, Na2C8H16O7S2—

Anti-A Blood Grouping Reagent, Anti-B Blood334.32—Use a suitable grade with a content of NLT 95%. Grouping Reagent, and Anti-AB Blood Grouping[NOTE—A suitable grade is available as catalog numberReagent—The reagents can be monoclonal or polyclonalRM-969-C50 from www.cydexpharma.com.]and must be obtained from manufacturers or suppliers li-Bismuth Nitrate Pentahydrate, Bi(NO3)3 · 5H2O—485.07censed by the Center for Biologics Evaluation and Research,[10035-06-0]—Use ACS reagent grade.Food and Drug Administration for use in microplate tests.Bismuth Subnitrate (Bismuth(III) Nitrate Basic),The use of reagents from an unlicensed manufacturer orBi5O (OH)9(NO3)4—1461.99 [1304-85-4]—Use Bismuthsupplier may invalidate the results. Generally, all three re-Subnitrate (USP monograph).agents are available as part of a kit.Bismuth Sulfite Agar—Use a suitable grade.

[NOTE—There are many manufacturers and suppliers ofBis(trimethylsilyl)acetamide (N,O-Bis(trimethylsil-these reagents that are licensed by the Center for Biologicsyl)acetamide; BSA), CH3CON[Si(CH3)3]2—203.43Evaluation and Research, Food and Drug Administration.[10416-59-8]—Clear, colorless liquid. Readily hydrolyzesSome examples of licensed manufacturers or suppliers arewhen exposed to moist air. Handle under nitrogen, andthe following: Gamma Biologics, Houston, TX; and Orthostore in a cool place.Diagnostics, Raritan, NJ.]Assay—Not less than 90% of CH3CON[Si(CH3)3]2, a suita- Blue Tetrazolium (3,3′-(3,3′-Dimethoxy[1,1′-biphenyl]-4,4′-ble gas chromatograph equipped with a thermal conductiv- diyl)bis[2,5-diphenyl-2H-tetrazolium]dichloride),ity detector being used. The following conditions are suita- C40H32Cl2N8O2—727.64 [1871-22-3]—Lemon-yellow crys-ble and provide a retention time of approximately tals. Slightly soluble in water; freely soluble in chloroform15 minutes. and in methanol; insoluble in acetone and in ether.

COLUMN: 3-mm × 1.83-m stainless steel containing 5% Solubility in methanol—Dissolve 1 g in 100 mL of metha-phase G1 on support S1A. nol: complete solution results, and the solution is clear.INJECTION TEMPERATURE: 160°. Color—Transfer a portion of the methanol solution ob-COLUMN TEMPERATURE: 90°, programmed to rise 4° per min- tained in the preceding test to a 1-cm cell, and determine

ute to 160°. its absorbance at 525 nm, against water as the blank: theCARRIER GAS: Helium. absorbance does not exceed 0.20.Refractive index ⟨831⟩: between 1.4150 and 1.4170 at Molar absorptivity ⟨851⟩—Its molar absorptivity in metha-

20°. nol, at 252 nm, is not less than 50,000.Bis(trimethylsilyl)trifluoroacetamide (N,O-Bis(trimethyl- Suitability test—

silyl)trifluoroacetamide; BSTFA), CF3CON[Si(CH3)3]2—257.40STANDARD PREPARATION—Dissolve in alcohol a suitable quan-[25561-30-2]—Clear, colorless liquid. Readily hydrolyzes tity of USP Hydrocortisone RS, previously dried at 105° forwhen exposed to moist air. Store in a cool place. 3 hours and accurately weighed, and prepare by stepwise

Assay—Not less than 98% of CF3CON[Si(CH3)3]2, a suita- dilution a solution containing about 10 µg per mL.ble gas chromatograph equipped with a thermal conductiv-

PROCEDURE—Pipet 10-, 15-, and 20-mL portions of Stan-ity detector being used. The following conditions are suita- dard Preparation into separate, glass-stoppered, 50-mL coni-ble and provide a retention time of approximately cal flasks. Add 10 mL and 5 mL, respectively, of alcohol to15 minutes. the flasks containing the 10- and 15-mL portions of Stan-COLUMN: 3-mm × 1.83-m stainless steel containing 5% dard Preparation, and swirl to mix. To each of the flasks, and

phase G1 on support S1A. to a fourth flask containing 20 mL of alcohol, add 2.0 mL ofINJECTION TEMPERATURE: 170°. a solution prepared by dissolving 50 mg of blue tetrazolium

in 10 mL of alcohol, mix, and then add 2.0 mL of a solutionCOLUMN TEMPERATURE: 70°, programmed to rise 4° per min-prepared by diluting 1 mL of tetramethylammonium hy-ute to 140°.droxide TS with alcohol to 10 mL. Mix, allow the flasks toCARRIER GAS: Helium.stand in the dark for 90 minutes, and determine the ab-Refractive index ⟨831⟩: between 1.3820 and 1.3860 at sorbances of the three solutions of the steroid standard at20°. 525 nm, with a suitable spectrophotometer, using the solu-Bis(trimethylsilyl)trifluoroacetamide with Trimethyl- tion in the fourth flask as the blank. Plot the absorbances onchlorosilane [25561-30-2]—Use a suitable grade. the abscissa and the amount of hydrocortisone on the ordi-[NOTE—A suitable grade is available from Sigma-Aldrich, nate scale of arithmetic coordinate paper, and draw thewww.sigma-aldrich.com.] curve of best fit: the absorbance of each solution is propor-Blood (for carbon monoxide test in gases)—Use oxalated tional to the concentration, and the absorbance of the solu-or defibrinated blood of dogs, sheep, cattle, or human beings tion containing 200 µg of hydrocortisone is not less thanwithin 24 hours after bleeding. Prepare oxalated blood by 0.50.adding 10 mg of sodium oxalate to each mL of the freshly Boric Acid, H3BO3—61.83 [10043-35-3]—Use ACS rea-drawn blood. gent grade.Blood Group A1 Red Blood Cells and Blood Group B (–)-Bornyl Acetate (1,7,7-Trimethylbicyclo[2,2,1]-heptan-Red Blood Cells—These cells must be obtained from manu- 2-ol acetate), C12H20O2—196.29 [5655-61-8]—Use afacturers or suppliers licensed by the Center for Biologics suitable grade.Evaluation and Research/Food and Drug Administration. The Boron Trifluoride, BF3—67.81 [7637-07-2]—Use ause of reagents from an unlicensed manufacturer or supplier suitable grade.may invalidate the results. Generally, they are available as 14% Boron Trifluoride–Methanol [373-57-9]—Use apart of a kit for ABO Blood Group testing. The cells licensed suitable grade.for use in test tubes can also be used in the microtiter plate Bovine Collagen—Use a suitable grade that contains lessmethod described in the monographs of Red Blood Cells and than 1 µg glycosaminoglycan per mg.Whole Blood.


[NOTE—A suitable grade is available from Sigma-Aldrich, in water. Miscible with alcohol and with ether. Boils atwww.sigma-aldrich.com.] about 88°.

7 Percent Bovine Serum Albumin Certified Standard— Assay—Available from the National Institute of Standards and Tech- HYDROXYLAMINE HYDROCHLORIDE SOLUTION—Dissolve 20 g ofnology, www.nist.gov, as SRM 927. hydroxylamine hydrochloride in 40 mL of water, and diluteBranched Polymeric Sucrose—about 400 kDa with alcohol to 400 mL. Add, with stirring, 300 mL of 0.5 N[26873-85-8]—White to off-white powder. Synthetic poly- alcoholic potassium hydroxide VS, and filter. Discard after 2mer made by the copolymerization of sucrose and days.epicholrohydrin. Use a suitable grade.

PROCEDURE—Transfer about 1 g, accurately weighed, to a[NOTE—A suitable grade is available commercially asglass-stoppered, 250-mL flask, add 75.0 mL of Hydroxyla-“Ficoll” from Pharmacia Fine Chemicals, Inc., 800 Centen-mine hydrochloride solution,and insert the stopper in thenial Ave., Piscataway, NJ 08854.]flask. Reflux the mixture for 1 hour, then cool to room tem-Brilliant Green (Malachite Green G), C27H34N2O4S—perature. Add bromophenol blue TS, and titrate with 0.5 N482.64 [3051-11-4]—Glistening, golden-yellow crystals.hydrochloric acid VS to a greenish-yellow endpoint. [NOTE—Soluble in water and in alcohol. Absorption maximum: 623Alternatively, the solution may be titrated potentiometricallynm.to a pH of 3.4.] Perform a blank test with the same quanti-Bromelain—A proteolytic enzyme isolated from pineap-ties of reagent used for the test specimen, and make anyple. Use a suitable grade.necessary correction. Each mL of 0.5 N hydrochloric acid isBromine, Br—At. Wt. 79.904 [7726-95-6]—Use ACSequivalent to 43.05 mg of CH3COCOCH3. Not less thanreagent grade.97% of CH3COCOCH3 is found.α-Bromo-2′-acetonaphthone (Bromomethyl 2-naphthyl

Congealing temperature ⟨651⟩: between −2.0° andketone), C12H9BrO—249.10—Tannish–pink crystals.−5.5°.Melting range ⟨741⟩: between 81° and 83°.

Refractive index ⟨831⟩: between 1.3935 and 1.3965, atp-Bromoaniline, C6H6BrN—172.02 [106-40-1]—White20°.to off-white crystals. Insoluble in water; soluble in alcohol

and in ether. Specific gravity ⟨841⟩: about 0.98.1-Butanesulfonic Acid Sodium Salt (SodiumAssay—Transfer about 650 mg, accurately weighed, to a

1-butanesulfonate), C4H9NaO3S—160.16 [2386-54-1]—suitable container, and dissolve in 50 mL of glacial aceticUse a suitable grade with a content of not less than 99.0%.acid TS. Add crystal violet TS, and titrate with 0.1 N per-

1,4-Butane Sultone (4-Hydroxybutane-1-sulfonic Acidchloric acid VS. Perform a blank determination, and makedelta-sultone), C4H8O3S—136.17 [1633-83-6]—Use a suit-any necessary correction. Each mL of 0.1 N perchloric acidable grade with a content of NLT 99%.is equivalent to 17.20 mg of C6H6BrN. Not less than 98% is

Butanol—See Butyl Alcohol.found.Butyl Acetate, Normal, CH3COO(CH2)3CH3—116.16Melting range ⟨741⟩: between 60° and 65°, within a 2°

[123-86-4]—Use ACS reagent grade.range.Butyl Alcohol (1-Butanol; Normal Butyl Alcohol), CH3Bromofluoromethane—Use a suitable grade.

(CH2)2CH2OH—74.12 [71-36-3]—Use ACS reagent grade.N-Bromosuccinimide, C4H4BrNO2—177.98Butyl Alcohol, Normal—See Butyl Alcohol.[128-08-5]—White to off-white crystals or powder. FreelyButyl Alcohol, Secondary (2-Butanol),soluble in water, in acetone, and in glacial acetic acid.

CH3CH2CH(OH)CH3—74.12 [78-92-2]—Use a suitable[CAUTION—Highly irritating to eyes, skin, and mucousgrade with a content of NLT 99%.membranes.]

Butyl Alcohol, Tertiary, (CH3)3COH—74.12Assay—Transfer 200 mg, accurately weighed, to a conical [75-65-0]—Use ACS reagent grade tert-Butyl Alcohol.flask, add 25 mL of 0.5 N alcoholic potassium hydroxide, Butyl Benzoate, C11H14O2—178.23 [136-60-7]—Thick,cover with a watch glass, heat to boiling, and boil for oily, colorless to pale yellow liquid. Practically insoluble in5 minutes. Cool, transfer the solution to a beaker, rinsing water; soluble in alcohol and in ether.the flask with water until the total volume of solution plusAssay—When examined by gas-liquid chromatography, itrinsings is about 100 mL, and add 10 mL of glacial acetic

shows a purity of not less than 98%. The following condi-acid. Insert suitable electrodes, and titrate with 0.1 N silvertions have been found suitable for assaying it: use a 3-mm ×nitrate VS, determining the endpoint potentiometrically.1.8-m stainless steel column packed with liquid phase G4Each mL of 0.1 N silver nitrate is equivalent to 17.80 mg ofon support S1A. Helium is the carrier gas, the injection portC4H4BrNO2. Not less than 98% is found.temperature is maintained at 180°, the column temperatureBrucine Sulfate, (C23H26N2O4)2 · H2SO4 · 7H2O—1013.11is maintained at 190°, and the flame-ionization detector is[5787-00-8]—Use ACS reagent grade.maintained at 280°. The retention time is about 15 minutes.Buffers—See Buffer Solutions under Solutions.

Refractive index ⟨831⟩: between 1.4980 and 1.5000, at1,3-Butanediol (1,3-Butylene Glycol), C4H10O2—90.1220°.[107-88-0]—Viscous, colorless liquid. Very hygroscopic. Solu-

n-Butyl Chloride (1-Chlorobutane), C4H9Cl—92.57ble in water, in alcohol, in acetone, and in methyl ethyl[109-69-3]—Clear, colorless, volatile liquid. [CAUTION—ketone; practically insoluble in aliphatic hydrocarbons, inHighly flammable.] Practically insoluble in water. Misciblebenzene, and in toluene.with alcohol and with ether. Use HPLC grade.Assay—Inject an appropriate specimen into a suitable gas

Butyl Ether (n-Dibutyl Ether), C8H18O—130.23chromatograph (see Chromatography ⟨621⟩) equipped with[142-96-1]—Use a suitable grade.a flame-ionization detector, helium being used as the carrier

Butyl Methacrylate, C8H14O2—142.20 [97-88-1]—Usegas. The following conditions have been found suitable: aa suitable grade.3-mm × 1.8-m stainless steel column containing 20% phase

tert-Butyl Methyl Ether, C5H12O—88.15G16 on support S1A; the injection port temperature is[1634-04-4]—Colorless liquid.maintained at 265°; the column temperature is maintained

Assay—Inject an appropriate specimen into a gas chro-at 150° and programmed to rise 8° per minute to 210°. Thematograph (see Chromatography ⟨621⟩) equipped with aarea of the butanediol peak is not less than 98% of the totalflame-ionization detector, helium being used as the carrierpeak area.gas. The following conditions have been found suitable: aRefractive index ⟨831⟩: between 1.4390 and 1.4410 at0.25-mm × 30-m capillary column coated with a 1-µm layer20°.of phase G2; the injection port temperature is maintained at2,3-Butanedione (Diacetyl), CH3COCOCH3—86.09100°; the detector temperature is maintained at 300°; and[431-03-8]—Bright yellow to yellowish-green liquid. Solublethe column temperature is maintained at ambient tempera-


ture and programmed to rise 10° per minute to 150°. The Assay—Weigh accurately about 500 mg, transfer to aarea of the C5H12O peak is not less than 99.8% of the total suitable container, add 30 mL of water, and mix. Add 40 mLpeak area. of water, and mix. Add phenolphthalein TS, and titrate with

0.1 N sodium hydroxide VS. Each mL of 0.1 N sodium hy-Refractive index ⟨831⟩: between 1.367 and 1.371 at 20°.droxide is equivalent to 8.81 mg of C4H8O2: not less thann-Butylamine, CH3CH2CH2CH2NH2—73.1499.0% of C4H8O2 is found.[109-73-9]—Colorless to pale yellow, flammable liquid. Mis-

cible with water, with alcohol, and with ether. Store it in Refractive index ⟨831⟩: about 1.398 at 20°.tight containers. Specific gravity: about 0.740. Butyrolactone (Dihydro-2-(3H)-furanone, γ-butyrolactone)

—86.1 [96-48-0]—Clear, colorless to practically colorless,Distilling range, Method I ⟨721⟩—Not less than 95% dis-oily liquid. Miscible with water. Soluble in methanol and intills between 76° and 78°.ether.Water, Method I ⟨921⟩: not more than 1.0%, determined

Boiling range ⟨721⟩: between 193° and 208°.by the Titrimetric Method.Refractive index ⟨831⟩: about 1.435, at 20°.Chloride (Reagent test)—One g (1.5 mL) shows not more

than 0.01 mg of Cl (0.001%). Specific gravity ⟨841⟩: between 1.128 and 1.135.Butyrophenone (Phenyl Propyl Ketone), C10H12O—148.21Acidic impurities—To 50 mL add 5 drops of a saturated

[495-40-9]—Use a suitable grade with a content of not lesssolution of azo violet in benzene, and titrate quickly withthan 98.0%.0.1 N sodium methoxide VS to a deep blue endpoint, ob-

Cadmium Acetate, C4H6CdO4 · 2H2O—266.53serving precautions to prevent absorption of atmospheric[543-90-8]—Colorless, transparent to translucent crystals.carbon dioxide as by use of an atmosphere of nitrogen: notFreely soluble in water; soluble in alcohol.more than 1.0 mL of 0.1 N sodium methoxide is required

for neutralization. Insoluble matter (Reagent test): not more than 1 mg,tert-Butylamine, C3H9CNH2—73.14 [75-64-9]—Liquid. from 20 g (0.005%).Assay—Inject an appropriate volume into a gas chromat- Chloride (Reagent test)—One g shows not more than

ograph (see Chromatography ⟨621⟩) equipped with a flame- 0.01 mg of Cl (0.001%).ionization detector, helium being used as the carrier gas. Sulfate (Reagent test, Method II)—Dissolve 10 g inThe following conditions have been found suitable: a 0.25- 100 mL of water, add 1 mL of hydrochloric acid, and filter:mm × 30-m capillary column coated with a 1-µm layer of the residue weighs not more than 1.2 mg more than thephase G2; the injection port temperature is maintained at residue obtained in a complete blank test (0.005%).230°; the detector temperature is maintained at 300°; the Substances not precipitated by hydrogen sulfide—Dissolvecolumn temperature is maintained at 130° and pro- 2 g in a mixture of 135 mL of water and 15 mL of 1 N sulfu-grammed to rise 10° per minute to 280°. The area of the ric acid, heat to boiling, and pass a rapid stream of hydro-C3H9CNH2 peak is not less than 99.5% of the total peak gen sulfide through the solution as it cools. Filter, and toarea. 75 mL of the clear filtrate add 0.25 mL of sulfuric acid, then

Refractive index ⟨831⟩: between 1.3770 and 1.3790 at evaporate to dryness, and ignite gently: the residue weighs20°. not more than 1 mg (0.1%).

4-(Butylamino)benzoic Acid, C11H5NO2—193.25 Cadmium Nitrate, Cd(NO3)2 · 4H2O—308.48[4740-24-3]—Use a suitable grade. [10325-94-7]—Colorless, hygroscopic crystals. Very soluble

[NOTE—A suitable grade is available from Sigma-Aldrich, in water; soluble in alcohol.Inc., P.O. Box 2060, Milwaukee, WI 53201; www.sigma- Insoluble matter (Reagent test): not more than 1 mg,aldrich.com.] from 20 g (0.005%).n-Butylboronic Acid (1-Butaneboronic Acid),

Chloride (Cl) (Reagent test)—One g shows not more thanC4H9B(OH)2—101.94 [4426-47-5]—Use a suitable grade.0.01 mg of Cl (0.001%).[NOTE—This reagent is usually shipped and stored under

Sulfate (Reagent test, Method II)—Evaporate a mixture ofwater. Before use, remove any excess water by light vacuum12 g of specimen and 25 mL of hydrochloric acid on afiltration. A suitable grade is available from Sigma-Aldrich,steam bath to dryness. Add another 15 mL of hydrochloricwww.sigma-aldrich.com.]acid, and again evaporate to dryness. Dissolve the residue intert-Butyldimethylchlorosilane in N-Methyl-N-tert-100 mL of water, filter, and add 1 mL of hydrochloric acid:butyldimethylsilyltrifluoroacetamide, (1 in 100)—Use athe residue weighs not more than 1.0 mg more than thesuitable grade.residue obtained in a blank test (0.003%).[NOTE—A suitable grade is available as 99% MTBSTFA, 1%

TBDMCS from Regis Chemical Company, 8210 Austin Ave., Copper (Cu)—Dissolve 0.5 g in 10 mL of water, addP.O. Box 519, Morton Grove, IL 60053.] 10 mL of Ammonium Citrate Solution (see Lead ⟨251⟩), and

4-tert-Butylphenol, C10H14O—150.22 [98-54-4]— adjust the reaction to a pH of about 9 by the addition ofWhite, crystalline flakes or needles. Practically insoluble in 1 N ammonium hydroxide (about 30 mL). Add 1 mL of so-water; soluble in alcohol and in ether. dium diethyldithiocarbamate solution (1 in 1000), and mix.

Add 5 mL of amyl alcohol, shake for about 1 minute, andMelting range ⟨741⟩: between 98° and 101°.allow the layers to separate: any yellow color in the amylt-Butylthiol (tert-Butylthiol; tert-Butyl Mercaptan; 2-Methyl-alcohol layer is not darker than that of a blank to which2-propanethiol; TBM), (CH3)3CSH—90.19 [75-66-1]—Use a0.01 mg of Cu has been added (0.002%).suitable grade with a content of NLT 98.0%.

[NOTE—A suitable grade is available as catalog number Iron (Fe)—Dissolve 1 g in 15 mL of water, add 2 mL of20230 at www.sigma-aldrich.com.] hydrochloric acid, and boil for 2 minutes. Cool, and add

Butyraldehyde (Butanal), C4H8O—72.11 [123-72-8]— about 30 mg of ammonium persulfate and 15 mL of a solu-Use a suitable grade, purified by redistillation, with a con- tion of potassium thiocyanate in normal butyl alcohol (madetent of not less than 99.5%. by dissolving 10 g of potassium thiocyanate in 10 mL of

Butyric Acid, C4H8O2—88.11 [107-92-6]—Clear, col- water, warming the solution to about 30°, diluting with nor-orless to faint yellow liquid. Miscible with water and with mal butyl alcohol to 100 mL, and shaking until clear). Shakemethanol. vigorously for 30 seconds, and allow the layers to separate:

any red color in the clear alcoholic layer is not darker thanthat of a blank to which 0.01 mg of Fe has been added(0.001%).

Lead (Pb)—Dissolve 1.0 g in 10 mL of water, add 0.2 mLof glacial acetic acid, and filter if necessary. To a 7-mL por-tion of water add 0.2 mL of glacial acetic acid and 3 mL of


Standard Lead Solution (see Lead ⟨251⟩), and mix, to provide Calcium oxide and carbonate—Triturate 1 g of calcium cit-a blank. Then add to each solution 1.0 mL of potassium rate with 5 mL of water for 1 minute: the mixture does notchromate solution (1 in 10), and mix: after 5 minutes, the turn red litmus blue. Then add 5 mL of warm 3 N hydro-test solution is not more turbid than the blank (0.003%). chloric acid: only a few isolated bubbles escape.

Substances not precipitated by hydrogen sulfide—Dissolve Hydrochloric acid-insoluble matter—Dissolve 5 g by heating2 g in 145 mL of water, add 5 mL of sulfuric acid (1 in 10), with a mixture of 10 mL of hydrochloric acid and 50 mL ofheat to boiling, and pass a rapid stream of hydrogen sulfide water for 30 minutes: not more than 2.5 mg of insolublethrough the solution as it cools. Filter, and to 75 mL of the residue remains (0.05%).clear filtrate add 0.25 mL of sulfuric acid, then evaporate to Loss on drying ⟨731⟩—Dry it at 150° to constant weight:dryness, and ignite gently: the residue weighs not more it loses between 12.2% and 13.3% of its weight.than 1 mg (0.1%). Arsenic ⟨211⟩—Proceed with 0.50 g as directed for or-Calcium Acetate, Ca(C2H3O2)2 · H2O—176.18 ganic compounds (6 ppm of As).[5743-26-0]—White, crystalline granules or powder. Soluble

Heavy metals, Method I ⟨231⟩: 0.002%.in about 3 parts of water; slightly soluble in alcohol. UseCalcium Hydroxide [1305-62-0]—Use ACS reagent grade.ACS reagent grade.Calcium Lactate, (CH3CHOHCOO)2Ca · 5H2O—308.29Calcium Carbonate, CaCO3—100.09 [471-34-1]—Use

[814-80-2]—White granules or powder. Is somewhat efflo-ACS reagent grade.rescent and at 120° becomes anhydrous. One g dissolves in[NOTE—Calcium Carbonate of a quality suitable as a pri-20 mL of water; practically insoluble in alcohol. Store it inmary standard is available from the National Institute oftight containers.Standards and Technology, Office of Standard Reference

Assay—Accurately weigh about 500 mg, previously driedMaterials, www.nist.gov, as standard sample No. 915.]at 120° for 4 hours, transfer to a suitable container, andCalcium Carbonate, Chelometric Standard, CaCO3—dissolve in 150 mL of water containing 2 mL of diluted hy-100.09 [471-34-1]—Use ACS reagent grade.drochloric acid. Add 15 mL of sodium hydroxide TS andCalcium Caseinate—White or slightly yellow, nearly300 mg of hydroxy naphthol blue indicator, and titrate withodorless, powder. Insoluble in cold water, but forms a milky0.05 M edetate disodium VS until the solution is deep blue.solution when suspended in water, stirred, and heated.Each mL of 0.05 M edetate disodium is equivalent toResidue on ignition (Reagent test)—Ignite 5 g at 550°: the10.91 mg of C6H10CaO6. Not less than 98% is found.residue weighs between 150 and 300 mg (3.0% to 6.0%).

Loss on drying ⟨731⟩—Dry it at 120° for 4 hours: it losesCalcium—Treat the residue from the preceding test withbetween 25.0% and 30.0% of its weight.10 mL of diluted hydrochloric acid, filter, and to the clear

Acidity—Add phenolphthalein TS to 20 mL of a 1 in 20filtrate add 5 mL of ammonium oxalate TS: it shows a whitesolution, and titrate with 0.10 N sodium hydroxide: notprecipitate upon standing.more than 0.50 mL is required to produce a pink color.Loss on drying ⟨731⟩—Dry it in vacuum at 70° to constant

Heavy metals (Reagent test)—Dissolve 1 g in 2.5 mL ofweight: it loses not more than 7.0% of its weight.diluted hydrochloric acid, dilute with water to 40 mL, andFat—Suspend 1.0 g in 5 mL of alcohol in a Mojonnieradd 10 mL of hydrogen sulfide TS: any brown color pro-flask, add 0.8 mL of stronger ammonia water and 9 mL ofduced is not darker than that of a control containingwater, and shake. Add a second 5-mL portion of alcohol,0.02 mg of added Pb (0.002%).then add successive portions of 25 mL each of ether and

Magnesium and alkali salts—Mix 1 g with 40 mL of water,solvent hexane, shaking after each addition by inverting thecarefully add 5 mL of hydrochloric acid, heat the solution,flask 30 times. Centrifuge, decant the solvent layer, evapo-boil for 1 minute, and add rapidly 40 mL of oxalic acid TS.rate it at a low temperature, and dry on a steam bath: theAdd immediately to the warm mixture 2 drops of methylresidue weighs not more than 20 mg (2.0%).red TS, then add ammonia TS dropwise, from a buret, untilNitrogen content, Method I ⟨461⟩—Between 12.5% andthe mixture is just alkaline. Cool to room temperature,14.3% of N is found, calculated on the anhydrous basis.transfer to a 100-mL graduated cylinder, dilute with waterSuspensibility in water—Place 2 g in a beaker, and add to 100 mL, mix, and allow to stand for 4 hours or overnight.cool water slowly with stirring to form a thin, smooth paste. Filter, and transfer to a platinum dish 50 mL of the clearAdd additional water to make a total of 100 mL. Stir, and filtrate, to which has been added 0.5 mL of sulfuric acid.heat to 80°: a milky suspension is formed that does not Evaporate the mixture on a steam bath to a small bulk.settle after standing for 2 hours. Carefully heat over a free flame to dryness, and continueCalcium Chloride, CaCl2 · 2H2O—147.01 heating to complete decomposition and volatilization of am-[10035-04-8]—Use ACS reagent grade Calcium Chloride Di- monium salts. Finally ignite the residue at 800 ± 25° forhydrate. 15 minutes: the residue weighs not more than 5 mg (1%).Calcium Chloride, Anhydrous (for drying), CaCl2— Volatile fatty acid—Stir about 500 mg with 1 mL of sulfu-110.98 [10043-52-4]—Use ACS reagent grade Calciumric acid, and warm: the mixture does not emit an odor ofChloride Desiccant.volatile fatty acid.Calcium Citrate, Ca3(C6H5O7)2 · 4H2O—570.49

Calcium Nitrate, Ca(NO3)2 · 4H2O—236.15[813-94-5]—A white, crystalline powder. Slightly soluble in[13780-06-8]—Use ACS reagent grade.water; freely soluble in 3 N hydrochloric acid and in 2 N

Calcium Pantothenate, Dextro—Use Calcium Pantothen-nitric acid; insoluble in alcohol. To 15 mL of hot 2 N sulfuricate (USP monograph).acid add in small portions and with stirring about 500 mg

Calcium Sulfate, CaSO4 · 2H2O—172.17of calcium citrate. Boil the mixture for 5 minutes, and filter[7778-18-9]—Use ACS reagent grade.while hot: the cooled filtrate responds to the identification

Calconcarboxylic Acid (2-Naphthalenecarboxylic acid,test for Citrate ⟨191⟩.3-hydroxy-4-[(2-hydroxy-4-sulfo-1-naphthalenyl)azo]; Calcon-Assay—Accurately weigh about 400 mg of the salt, previ- 3-carboxylic Acid; Cal-Red), C21H14N2O7S—438.42ously dried at 150° to constant weight, and transfer to a [3737-95-9]—Use a suitable grade.250-mL beaker. Dissolve the test specimen in 150 mL of Calconcarboxylic Acid Triturate—Mix 1 part of calcon-water containing 2 mL of 3 N hydrochloric acid, add 15 mL carboxylic acid with 99 parts of sodium chloride.of 1 N sodium hydroxide and 250 mg of hydroxy naphthol

Test for sensitivity—Dissolve 50 mg of calconcarboxylicblue, and titrate with 0.05 M edetate disodium VS until theacid triturate in a mixture of 2 mL 10 N sodium hydroxidesolution turns deep blue. Each mL of 0.05 M edetate diso-and 100 mL of water. The solution is blue but becomes vio-dium is equivalent to 8.307 mg of Ca3(C6H5O7)2: betweenlet on addition of 1 mL of a 10 g per L solution of magne-97.5% and 101% is found.sium sulfate and 0.1 mL of a 1.5 g per L solution of calcium


chloride and turns pure blue on addition of 0.15 mL of 0.01 Measuring range: 5 to 150 ppm.M sodium edetate. [NOTE—Available from Draeger Safety, Inc.,

Calf Thymus DNA—Use a suitable grade. [NOTE—A suita- www.draeger.com, or from Gastec Corp., www.gastec.co.jp,ble grade is commercially available from Worthington Bio- distributed in the USA by www.nextteq.com.]chemical Corp., www.worthington-biochem.com.] Carbon Tetrachloride, CCl4—153.82 [56-23-5]—Use

dl-Camphene, C10H16—136.24 [79-92-5]—Use a suita- a grade meeting the specifications of ACS Reagent Chemi-ble grade. cals, 8th Edition.

[NOTE—A suitable grade is available as camphene, 95%, Carboxylate (Sodium Form) Cation-exchange Resincatalog number 45,606-5, from Sigma-Aldrich, www.sigma- (50- to 100-mesh)—See Cation-Exchange Resin, Carboxylatealdrich.com.] (Sodium Form) (50- to 100-mesh).

d-10-Camphorsulfonic Acid [(1S)-(+)-10-Camphorsulfonic Carboxymethoxylamine Hemihydrochloride,acid; (1S)-Camphor-10-sulfonic acid; (+)-Camphor-10-sulfonic 2(C2H5NO3) · HCl—218.59 [2921-14-4]—White, crystal-acid (β)], C10H16O4S—232.30 [3144-16-9]—Use a suitable line powder. Use a suitable grade.grade. Carmine (Alum Lake of Carminic Acid), C22H20O13 · xAl

[NOTE—A suitable grade is available as catalog number [1390-65-4]—Red powder. Use a suitable grade.C2107 from www.sigma-aldrich.com.] (R)-(–)-Carvone (2-Methyl-5-(1-methylethenyl)-2-cyclohex-

dl-10-Camphorsulfonic Acid, [Camphor-10-sulfonic acid ene-1-one), C10H14O—150.22 [6485-40-1]—Use a suitable(β)]; [(RS)-10-Camphorsulfonic acid], C10H16O4S—232.30 grade.[5872-08-2]— Is optically inactive. Casein [9000-71-9]—White or slightly yellow, granular

Use a suitable grade. powder. Insoluble in water and in other neutral solvents;[NOTE—A suitable grade is available as catalog number readily dissolved by ammonia TS and by solutions of alkali

147923 from www.sigma-aldrich.com.] hydroxides, usually forming a cloudy solution.Canada Balsam [8007-47-4]—A natural product derived Residue on ignition (Reagent test)—Ignite 2 g: the residue

from the resin of Abies balsamea. Use a suitable grade. weighs not more than 20 mg (1.0%).Canola Oil [120962-03-0]—Use a suitable grade. Loss on drying ⟨731⟩—Dry it at 105° to constant weight:Capric Acid (Decanoic Acid), C10H20O2—172.26 it loses not more than 10.0% of its weight.[334-48-5]—White, solidified melt or fragments. Soluble in

Alkalinity—Shake 1 g with 20 mL of water for 10 minutes,alcohol, in chloroform, and in ether; practically insoluble inand filter: the filtrate is not alkaline to red litmus paper.water.

Soluble substances—When the filtrate from the AlkalinityAssay—Inject an appropriate sample dissolved in acetonetest is evaporated and dried at 105°, the residue weighs notinto a gas chromatograph (see Chromatography ⟨621⟩) thatmore than 1 mg (0.1%).is equipped with a flame-ionization detector and contains a

Fats—Dissolve 1 g in a mixture of 10 mL of water and0.53-mm × 30-m capillary column coated with a layer of5 mL of alcoholic ammonia TS, and shake out with twophase G25. The carrier gas is helium, flowing at a rate of20-mL portions of solvent hexane. Evaporate the hexane at9 mL per minute. The chromatograph is programmed as fol-a low temperature, and dry at 80°: the weight of the resi-lows. Initially the column temperature is equilibrated atdue does not exceed 5 mg (0.5%).150°, then the temperature is increased at a rate of 10° per

minute to 250°. The injection port temperature is main- Nitrogen content, Method I ⟨461⟩: between 15.2% andtained at 240°, and the detector temperature at 265°. The 16.0% of N is found, on the anhydrous basis.area of the capric acid peak is not less than 98.5% of the Where vitamin-free casein is required, use casein that hastotal peak area. been rendered free from the fat-soluble vitamins by continu-

ous extraction with hot alcohol for 48 hours followed by air-Melting range ⟨741⟩: between 30° and 33°.drying to remove the solvent.Carbazole, C12H9N—167.21 [86-74-8]—Off-white to

Casein, Hammersten [9000-71-9]. [NOTE—A suitabletan powder.grade is available from www.emdchemicals.com, catalogAssay—Inject an appropriate volume into a gas chromat-number CX0525-1.]ograph (see Chromatography ⟨621⟩) equipped with a flame-

Catechol (o-Dihydroxybenzene; Pyrocathecol), C6H4(OH)2—ionization detector, helium being used as the carrier gas.110.11 [120-80-9]—White crystals, which become discol-The following conditions have been found suitable: a 0.25-ored on exposure to air and light. Readily soluble in water,mm × 30-m capillary column coated with a 1-µm layer ofin alcohol, in benzene, in ether, in chloroform, and in pyri-phase G2; the injection port temperature is maintained atdine, forming clear solutions.280°; the detector temperature is maintained at 300°; and

Use a suitable grade with a content of not less than 99%.the column temperature is maintained at 280°. The area ofCation-Exchange Resin—Use a suitable grade.the C12H9N peak is not less than 95.5% of the total peak[NOTE—A suitable grade is available commercially asarea.

“Dowex 50-W-X8-100,” from Sigma-Aldrich, www.sigma-Carbon Dioxide Detector Tube—A fuse-sealed glass tubealdrich.com.]so designed that gas may be passed through it. Contains

Cation-Exchange Resin, Carboxylate (Sodium Form)suitable absorbing filters and support media for the indica-(50- to 100-mesh)—Use a suitable grade.tors hydrazine and crystal violet.

[NOTE—A suitable grade is available as “Bio-Rex 70” fromMeasuring range: 0.01 to 0.3 Vol.–%. BioRad Laboratories, www.bio-rad.com.][NOTE—Available from Draeger Safety, Inc., Cation-Exchange Resin, Polystyrene—Use a suitablewww.draeger.com, or from Gastec Corp., www.gastec.co.jp, grade.distributed in the USA by www.nextteq.com.] [NOTE—A suitable grade is available as Dowex-50X2-100,Carbon Disulfide, Chromatographic—Use a suitable from Sigma-Aldrich, www.sigma-aldrich.com.]grade. Cation-Exchange Resin, Styrene-Divinylbenzene—ACarbon Disulfide, CS [75-15-0]—Use ACS reagent strongly acidic, cross-linked sulfonated resin containinggrade. about 2% of divinylbenzene. It is available in the hydrogenCarbon Monoxide Detector Tube—A fuse-sealed glass form in the 50- to 100-, 100- to 200-, and 200- totube so designed that gas may be passed through it. Con- 400-mesh sizes. It can be regenerated to the hydrogen formtains suitable absorbing filters and support media for the by treating with a hydrochloric acid solution (5 in 100). Forindicators iodine pentoxide and selenium dioxide and fum- satisfactory regeneration, a contact time of at least 30 min-ing sulfuric acid. utes is required after which it must be washed free of excessacid. It is insoluble in water, in methanol, and in acetoni-trile. Suitable for use in column chromatography.


Moisture content of fully regenerated and expanded resin— [NOTE—A suitable grade is available commercially, inTransfer 10 to 12 mL of the resin (as received) to a flask, precoated plate form, with fluorescent indicator, from EMDand convert it completely to the hydrogen form by stirring Chemicals, www.emdchemicals.com.]with 150 mL of hydrochloric acid solution (5 in 100) for not Ceric Ammonium Nitrate, Ce(NO3)4 · 2NH4NO3—less than 30 minutes. Decant the acid, and wash the resin in 548.22—Use ACS reagent grade.the same manner with water until the wash water is neutral Ceric Ammonium Sulfate, Ce(SO4)2 · 2(NH4)2SO4 ·to litmus (pH 3.5). 2H2O—632.55—Yellow to yellowish–orange crystals. Dis-

Transfer 5 to 7 mL of the regenerated resin to a glass solves slowly in water, but more rapidly when mineral acidsfiltering crucible, and remove only the excess surface water are present. Use ACS reagent grade.by very careful suction filtration. Transfer the conditioned Ceric Sulfate, Ce(SO4)2 with a variable amount ofresin to a tared weighing bottle, and weigh. Dry in a vac- water—(anhydrous) 332.24 [13590-82-4]—It may alsouum oven at a pressure of 50 mm of mercury at 100° to contain sulfates of other associated rare earth elements. Yel-105° for 16 hours. Transfer from the vacuum oven to a des- low to orange-yellow crystals or crystalline powder. Practi-iccator, cool to room temperature, and weigh again. The cally insoluble in cold water; slowly soluble in cold diluteloss in weight is between 75% and 83%. mineral acids, but more readily soluble when heated with

these solvents.Total wet volume capacity—Transfer 3 to 5 mL of theregenerated, undried (See Moisture content above) resin to a Assay—Weigh accurately about 800 mg, transfer to a5-mL graduated cylinder, and fill it with water. Remove any flask, add 25 mL of water and 3 mL of sulfuric acid, andair bubbles from the resin bed with a stainless steel wire, warm until dissolved. Cool, and add 60 mL of a mixture ofand settle the resin to its minimum volume by tapping the 1 volume of phosphoric acid and 20 volumes of water. Addgraduated cylinder. Record the volume of the resin. 25 mL of potassium iodide solution (1 in 10), insert the

Transfer the resin to a 400-mL beaker. Add about 5 g of stopper in the flask, and allow to stand for 15 minutes. Re-sodium chloride, and titrate, stirring well, with 0.1 N so- place the air over the solution with carbon dioxide, anddium hydroxide to the blue endpoint of bromothymol blue while continuing the flow of carbon dioxide into the flask,(pH 7.0). titrate the liberated iodine with 0.1 N sodium thiosulfate VS,

adding 3 mL of starch TS as the endpoint is approached.(net mL NaOH × N)/(mL of resin) = mEq/mL Each mL of 0.1 N sodium thiosulfate is equivalent to

33.22 mg of Ce(SO4)2. Not less than 80.0% is found.The total wet volume capacity of the resin is more than 0.6 Chloride (Reagent test)—Dissolve 1 g in a mixture of 5 mLmEq per mL. of nitric acid and 4 mL of water. Filter, if necessary, and

Wet screen analysis—The purpose of this test is to prop- dilute with water to 20 mL. To 10 mL of the dilution adderly identify the mesh size of the resin. To obtain an accu- 1 mL of silver nitrate TS, allow to stand for 10 minutes, andrate screen analysis would require a special apparatus and filter until clear. To the remaining 10 mL of test solution addtechnique. 1 mL of silver nitrate TS: any turbidity produced does not

Add 150 mL of resin to 200 mL of water in an appropriate exceed that in a control prepared by adding 0.05 mg of Clbottle, and allow it to stand at least 4 hours to completely to the filtrate obtained from the first 10 mL of test solutionswell the resin. (0.01%).

Transfer, by means of a graduated cylinder, 100 mL of Heavy metals—Heat 500 mg with a mixture of 10 mL ofsettled and completely swollen resin to the top screen of a water and 0.5 mL of sulfuric acid until solution is complete.series of the designated U.S. Standard 20.3-cm brass Cool, dilute with water to 50 mL, and bubble hydrogen sul-screens. Thoroughly wash the resin on each screen with a fide gas through the solution until it is saturated: the precip-stream of water until the resin is completely classified, col- itate that is formed is white or not darker than pale yellow.lecting the wash water in a suitable container. Wash the Iron—Dissolve 100 mg in a mixture of 5 mL of water andbeads remaining on the respective screens back into the 2 mL of hydrochloric acid, warming if necessary, and cool.100-mL graduate, and record the volume of settled resin on Transfer to a glass-stoppered cylinder, dilute with water toeach screen. At least 70% of the resin will be within the 25 mL, and add 5 mL of ammonium thiocyanate TS andspecific mesh size. 25 mL of ether. Shake gently, but well, and allow the layers[NOTE—A suitable resin is Dowex 50WX2, produced by to separate: any pink color in the ether layer is not darkerDow Chemical Co. (www.dow.com) and also available than that of a control, similarly prepared, containingthrough Sigma-Aldrich (www.sigma-aldrich.com).] 0.02 mg of added Fe (0.02%).Cation-Exchange Resin, Styrene-Divinylbenzene, Cesium Chloride, CsCl—168.36 [7647-17-8]—AStrongly Acidic—Use a suitable grade. white powder. Very soluble in water; freely soluble in meth-[NOTE—A suitable grade is available commercially as anol; practically insoluble in acetone. Use a suitable grade.“Dowex 50-W-X8-100,” from Sigma-Aldrich, www.sigma- Cetrimide—See Cetyltrimethylammonium Bromide.aldrich.com.] Cetyltrimethylammonium Bromide (CTAB; Cetrimide;Cation-Exchange Resin, Sulfonic Acid—Use a suitable Hexadecyltrimethylammonium Bromide), C19H42BrN—364.46grade. [57-09-0]—Use a suitable grade. For any chromatographic[NOTE—A suitable grade is available commercially as application, use a suitable grade with a content of not less“Amberlyst 15” or as “Dowex 50-W-X2” from Sigma- than 99.0%.Aldrich, www.sigma-aldrich.com.] Cetyltrimethylammonium Chloride, 25 Percent inCedar Oil (for clearing microscopic sections) Water, C19H42ClN—320.00—Use a suitable grade.[8000-27-9]—A selected, distilled oil from the wood of the Charcoal, Activated (Activated Carbon; Decolorizing Car-red cedar, Juniperus virginiana Linne (Fam. Pinaceae), should bon) C—12.01 [7440-44-0]—A fine, black powder, whichbe used for this purpose. Refractive index: about 1.504 at is the residue from the destructive distillation of various or-20°. For use with homogeneous immersion lenses, a spe- ganic materials, treated to increase its high capacity for ad-cially prepared oil having a refractive index of 1.5150 ± sorbing organic coloring substances, as well as nitrogenous0.0002 at 20° is required. bases. Use Activated Charcoal (USP monograph).Cellulose, Chromatographic—Use a suitable grade. Chenodeoxycholic Acid, C24H40O4—392.57[NOTE—A suitable grade is available from EMD Chemicals, [474-25-9]—White to off-white powder.www.emdchemicals.com.]

Assay—When tested by thin-layer chromatography, withCellulose, Microcrystalline—Use Cellulose, Microcrystal-the use of plates coated with chromatographic reversed-line, FCC.phase C18 mixture, a developing system consisting of 1 NCellulose Mixture, Chromatographic—Use a suitableacetic acid in methanol and 1 N acetic acid (19:1), andgrade.sprayed with a mixture of sulfuric acid and methanol (1:1),


heated at 110° for 20 minutes, and examined visually and benzene, in chloroform, and in ether. Use ACS reagentunder long-wavelength UV light, a single spot is exhibited. grade.

4-Chlorobenzoic Acid, ClC6H4COOH—156.57Melting range ⟨741⟩: between 165° and 168°.[74-11-3]—White, crystalline solid.Chloramine T (Sodium p-Toluenesulfonchloramide),

C7H7ClNNaO2S · 3H2O—281.69 [7080-50-4]—Use ACS Assay—Dissolve about 700 mg, accurately weighed, in areagent grade. mixture of 100 mL of hot alcohol and 50 mL of water. Ti-

Chlorine, Cl2—70.9 [7782-50-5]—Greenish-yellow trate with 0.5 N sodium hydroxide VS, determining thegas. High-purity grade available from most suppliers of spe- endpoint potentiometrically. Perform a blank determination,cialty gases. and make any necessary correction. Each mL of 0.5 N so-

Chlorine Detector Tube—A fuse-sealed glass tube so de- dium hydroxide is equivalent to 78.28 mg of ClC6H4COOH.signed that gas may be passed through it and containing Not less than 98% is found.suitable absorbing filters and support media for the indica- Solubility—One g dissolved in 25 mL of 0.5 N sodiumtor o-tolidine. hydroxide yields a clear and complete solution.

Measuring range: 0.2 to 3 ppm. m-Chlorobenzoic Acid (3-Chlorobenzoic Acid), [NOTE—Available from Draeger Safety, Inc., C7H5ClO2—156.57 [535-80-8]—Use a suitable grade.

www.draeger.com, or from Gastec Corp., www.gastec.co.jp, 4-Chlorobenzophenone, C13H9ClO—216.66distributed in the USA by www.nextteq.com.] [134-85-0]—Use a suitable grade.

m-Chloroacetanilide, C8H8ClNO—169.61—Off-white to 1-Chlorobutane—See n-Butyl Chloride.beige granules. 2-Chloroethanol (Ethylene Chlorohydrin), C2H5ClO—80.51

[107-07-3]—Use a suitable grade with a content of NLTAssay—99%.MOBILE PHASE—Prepare a mixture of acetonitrile and water 2-Chloroethylamine Monohydrochloride, C2H6ClN ·(22:3). HCl—115.99—Off-white powder.

PROCEDURE—Inject about 20 µL into a suitable liquid chro- Assay—Inject an appropriate specimen into a gas chro-matograph (see Chromatography ⟨621⟩) equipped with a matograph (see Chromatography ⟨621⟩) equipped with a254-nm detector and a 4.6-mm × 15-cm column that con- flame-ionization detector, helium being used as the carriertains packing L1. The flow rate is about 1.5 mL per minute. gas. The following conditions have been found suitable: aThe area of the C8H8ClNO peak is not less than 99.9% of 0.25-mm × 30-m capillary column coated with a 1-µm layerthe total peak area. of a phase consisting of 14% cyanopropylphenyl-86% di-Melting range ⟨741⟩: between 79° and 80°. methylpolysiloxane; the injection port temperature is main-

p-Chloroacetanilide, C8H8ClNO—169.61—White or pale tained at 150°; the detector temperature is maintained atyellow, needle-shaped crystals or crystalline powder. Insolu- 300°; and the column temperature is maintained at 50° andble in water; soluble in alcohol and in ether. programmed to rise 10° per minute to 200°. The area of

Solubility—One g dissolves in 30 mL of alcohol to form a the C2H6ClN · HCl peak is not less than 99% of the totalclear solution. peak area.

Melting range ⟨741⟩: between 178° and 181°. Melting range ⟨741⟩: between 150° and 246°.Chloroform, CHCl3—119.38 [67-66-3]—Use ACS rea-Residue on ignition (Reagent test): not more than

gent grade.0.1%.Chloroform, Alcohol-Free—Use a suitable grade that1-Chloroadamantane, C10H15Cl—170.68 [935-56-8]—

does not contain alcohol as a stabilizer.White crystalline solid.Chloroform, Methyl—See Methyl Chloroform.Assay—Inject an appropriate volume into a gas chromat-Chlorogenic Acid, C16H18O9—354.31 [327-97-9]—ograph (see Chromatography ⟨621⟩) equipped with a flame-

White to off-white powder. Use a suitable grade.ionization detector, helium being used as the carrier gas.Assay—When tested by thin-layer chromatography (seeThe following conditions have been found suitable: a 0.25-

Chromatography ⟨621⟩) with the use of plates coated withmm × 30-m capillary column coated with a 1-µm layer ofchromatographic silica gel mixture and a developing systemphase G2; the injection port temperature is maintained atconsisting of a mixture of butyl alcohol, water, and acetic250°; the detector temperature is maintained at 300°; andacid (60:25:15), and examined under short-wavelength UVthe column temperature is maintained at 150° and pro-light, a single spot is exhibited, with trace impurities.grammed to rise 10° per minute to 280°. The area of the

Chloromethylated Polystyrene-Divinylbenzene Anion-C10H15Cl peak is not less than 97.5% of the total peak area.exchange Resin—See Anion-exchange Resin, Chloromethyl-2-Chloro-4-aminobenzoic Acid—See 4-Amino-ated Polystyrene-Divinylbenzene.2-chlorobenzoic Acid.

1-Chloronaphthalene (α-Chloronaphthalene), C10H7Cl—5-Chloro-2-aminobenzophenone—See 2-Amino-162.62 [90-13-1]—Colorless to light yellow liquid.5-chlorobenzophenone.

3-Chloroaniline, C6H6ClN—127.57 [108-42-9]—Col- Assay—Use a gas chromatograph equipped with a flame-orless to light brown liquid. Soluble in acid and in most ionization detector. The following conditions have beenorganic solvents; practically insoluble in water. found suitable: a 3.2-mm × 1.83-m stainless steel column is

packed with 7% phase G2 on support S1A; the injectionAssay—Inject an appropriate specimen into a gas chro-port temperature is maintained at 250° and the detectormatograph (see Chromatography ⟨621⟩) equipped with atemperature at 310°; and the column temperature is pro-flame-ionization detector, helium being used as the carriergrammed to increase at a rate of 10° per minute from 50°gas. The following conditions have been found suitable: ato 250°. Not less than 90% of C10H7Cl is found, of which0.25-mm × 30-m capillary column coated with a 1-µm layernot more than 10% is 2-chloronaphthalene.of phase G2; the injection port temperature is maintained at

250°; the detector temperature is maintained at 300°; and Refractive index ⟨831⟩: between 1.6320 and 1.6340, atthe column temperature is maintained at 150° and pro- 20°.grammed to rise 10° per minute to 280°. The area of the 4-Chloro-1-naphthol, C10H7ClO—178.6 [604-44-4]—AC6H6ClN peak is not less than 99% of the total peak area. white to off-white powder, with a melting point between

118° and 120°. Use a suitable grade. Store below 0°.Refractive index ⟨831⟩: between 1.592 and 1.596 at2-Chloronicotinic Acid, C6H4ClNO2—157.5520°.

[2942-59-8]—Off-white powder.p-Chloroaniline, (4-Chloroaniline), C6H6ClN—127.57[106-47-8]—Use a suitable grade. Assay—Inject an appropriate volume into a gas chromat-

Chlorobenzene, C6H5Cl—112.56 [108-90-7]—Clear, ograph (see Chromatography ⟨621⟩) equipped with a flame-colorless liquid. Insoluble in water; soluble in alcohol, in ionization detector, helium being used as the carrier gas.


The following conditions have been found suitable: a 0.25- sponding brand names, are published periodically in Phar-mm × 30-m capillary column coated with a 1-µm layer of macopeial Forum as a guide for the chromatographer.]phase G2; the injection port temperature is maintained at Chromatographic Silica Gel—See Silica Gel, Chromato-280°; the detector temperature is maintained at 300°; and graphic.the column temperature is maintained at 180° and pro- Chromatographic Silica Gel Mixture—See Silica Gel Mix-grammed to rise 10° per minute to 280°. The area of the ture, Chromatographic.C6H4ClNO2 peak is not less than 98% of the total peak area. Chromatographic Siliceous Earth—See Siliceous Earth,

2-Chloro-4-nitroaniline, 99%, C6H5ClN2O2—172.57 Chromatographic.[121-87-9]—White to off-white powder. Chromatographic Siliceous Earth, Silanized—See Sili-

ceous Earth, Chromatographic, Silanized.Melting range ⟨741⟩: between 107° and 109°.Chromatographic Solvent Hexane—See Hexane, Solvent,Chloroplatinic Acid, H2PtCl6 · 6H2O—517.90

Chromatographic.[18497-13-7]—Use ACS reagent grade Chloroplatinic AcidChromium Potassium Sulfate Dodecahydrate,Hexahydrate.

CrK(SO4)2 · 12H2O—499.40 [10279-63-7]—Use ACS rea-5-Chlorosalicylic Acid, C7H5ClO3—172.57gent grade.[321-14-2]—White to off-white powder.

Chromium Trioxide, CrO3—99.99 [1333-82-0]—UseAssay—When tested by thin-layer chromatography (see ACS reagent grade.Chromatography ⟨621⟩) with the use of plates coated with Chromogenic Substrate for Amidolytic Test—Syntheticchromatographic silica gel mixture and a developing system molecules consisting of tripeptides or tetrapeptides coupledconsisting of a mixture of cyclohexane, chloroform, and ace- to a chromophore. The terminal amino acid is specific fortic acid (14:4:2), and examined visually and under long- the protease utilized. The synthetic peptides mimic the pep-wavelength UV light or iodine spray, a single spot is exhib- tide sequence (specific to the activated coagulation factor)ited. of the active site on the natural substrate. The coagulationMelting range ⟨741⟩: between 172° and 178°. factor catalyzes the splitting of the chromophore (p-ni-

1-Chloro-2,2,2-trifluoroethylchlorodifluoromethyl troaniline) from the peptide. The amount of release can beEther—Use a suitable grade. measured directly in a spectrophotometer, because the

Chlorotrimethylsilane (Trimethylsylyl Chloride), maximum absorbance spectra of the bound and free chro-C3H9ClSi—108.64 [75-77-4]—Clear, colorless to light yel- mophores differ. The released chromophore is a coloredlow liquid. Fumes when exposed to moist air. compound; the complete substrate itself is colorless.

[CAUTION—It reacts vigorously with water, alcohols, and Molecular weights of the various substrates range fromother hydrogen donors. Store in tight glass containers.] about 600 to 750 Da. Solubility in aqueous solutions can

Refractive index ⟨831⟩: between 1.3850 and 1.3890 at vary. Not all substrates are of equal sensitivity, and incuba-20°. tion periods may have to be extended.

Chlortetracycline Hydrochloride—Use Chlortetracycline Chromotrope 2R, C16H10N2Na2O8S2—468.4Hydrochloride (USP monograph). [4197-07-3]—Red powder or crystals. Use a suitable grade.

Cholestane, C27H48—372.67 [481-21-0]—Use a suita- Chromotropic Acid (4,5-Dihydroxy-2,7-ble grade. naphthalenedisulfonic Acid), C10H8O8S2 · 2H2O—356.33

Cholesterol, C27H46O—386.66 [57-88-5]—Use a suita- [148-25-4], for the anhydrous form—Use a suitable grade.ble grade (NFmonograph). Chromotropic Acid Disodium Salt (4,5-Dihydroxy-2,7-

Cholesteryl Benzoate, C34H50O2—490.76 [604-32-0]— naphthalenedisulfonic Acid, Disodium Salt), C10H6O8Na2S2 ·Use a suitable grade. 2H2O—400.29 [5808-22-0]—Use ACS reagent grade.

Cholesteryl n-Heptylate—Use a suitable grade. Cinchonidine, C19H22N2O—294.39 [485-71-2]—WhiteCholine Chloride, HOCH2CH2N(CH3)3Cl—139.62 crystals, crystalline or granular powder. Soluble in alcohol

[67-48-1]—White crystals or crystalline powder. Very soluble and in chloroform; practically insoluble in water.in water. Is hygroscopic. Store in tight containers. Assay—Dissolve about 125 mg, accurately weighed, in

Assay—Transfer about 100 mg, previously dried at 105° 50 mL of glacial acetic acid. Add a few drops of p-naphthol-for 2 hours and accurately weighed, to a beaker, add 20 mL benzein TS, and titrate with 0.1 N perchloric acid VS. Per-of water and 1 drop of aluminum chloride solution (1 in form a blank determination, and make any necessary correc-10), and mix. Add slowly 20 mL of a freshly prepared, tion. Each mL of 0.1 N perchloric acid is equivalent tofiltered sodium tetraphenylborate solution (1 in 50), and al- 14.72 mg of C19H22N2O. Not less than 99.0% is found.low the mixture to stand for 30 minutes with occasional Loss on drying ⟨731⟩—Dry it at 105° to constant weight:swirling. Pass through a medium-porosity, sintered-glass fil- it loses not more than 1.0% of its weight.ter, and wash the beaker and the precipitate with four Melting range ⟨741⟩: between 200° and 205°.10-mL portions of water. The weight of the precipitate, de-

Specific rotation ⟨781⟩: between −105° and −115°, calcu-termined after drying at 105° for 2 hours, and multiplied bylated on the dried basis, determined in a solution in alcohol0.3298, gives the equivalent weight of C5H14ClNO. Not lesscontaining 10 mg per mL.than 99.5% is found.

Cinchonine, C19H22N2O—294.39 [118-10-5]—WhiteResidue on ignition ⟨281⟩: not more than 0.1%. crystals, crystalline or granular powder. Slightly soluble inChromatographic Fuller’s Earth—See Fuller’s Earth, Chro- chloroform, sparingly soluble in alcohol, and practically in-matographic. soluble in water.Chromatographic n-Heptane—See n-Heptane, Chromato-Assay—Dissolve about 125 mg, accurately weighed, ingraphic.

50 mL of glacial acetic acid. Add a few drops of p-naphthol-Chromatographic Magnesium Oxide—See Magnesiumbenzein TS, and titrate with 0.1 N perchloric acid VS. Per-Oxide, Chromatographic.form a blank determination, and make any necessary correc-Chromatographic Reagents—See Reagents, Chromato-tion. Each mL of 0.1 N perchloric acid is equivalent tographic Reagents.14.72 mg of C19H22N2O. Not less than 99.0% is found.[NOTE—Listings of the numerical designations for phases

(G), packings (L), and supports (S), together with corre- Loss on drying ⟨731⟩—Dry it at 105° to constant weight:it loses not more than 1.0% of its weight.


Melting range ⟨741⟩: between 255° and 261°. ble in alcohol and in acetone. Melts at about 220°, withdecomposition.Specific rotation ⟨781⟩: between +219° and +229°, cal-

culated on the dried basis, determined in a solution in alco- Absorption maximum—The UV absorption spectrum of a 1hol containing 50 mg per 10 mL. in 100,000 solution in alcohol shows a maximum at about

Citric Acid—Use Citric Acid Monohydrate (USP mono- 238 nm.graph). Specific rotation ⟨781⟩: about +209°, determined in a 1 in

Citric Acid, Anhydrous [77-92-9]—Use Anhydrous Citric 100 solution in alcohol.Acid (USP monograph). Cotton, Absorbent—Use Purified Cotton (USP mono-

Cobalt Chloride (Cobaltous Chloride), CoCl2 · 6H2O— graph).237.93 [7791-13-1]—Use ACS reagent grade. m-Cresol Purple, C21H18O5S—382.43 [2303-01-7]—

Cobalt Nitrate, Co(NO3)2 · 6H2O—291.03 Use a suitable grade.[10026-22-9]—Use ACS reagent grade. Cupric Acetate, Cu(C2H3O2)2 · H2O—199.65

Cobaltous Acetate (Cobalt Acetate), Co(C2H3O2)2 · [6046-93-1]—Use ACS reagent grade.4H2O—249.08 [71-48-7]—Red, needlelike crystals. Solu- Cupric Chloride, CuCl2 · 2H2O—170.48ble in water and in alcohol. Use ACS reagent grade. [7447-39-4]—Bluish-green deliquescent crystals. Freely solu-

Cobaltous Chloride—See Cobalt Chloride. ble in water; soluble in alcohol; slightly soluble in ether. UseCoenzyme Q9 (Ubiquinone 45), C54H82O4—795.2 ACS reagent grade.

[303-97-9]—Yellow to yellow-orange powder. Clear yellow Cupric Citrate ([Citrato(4-)]dicopper), Cu2C6H4O7—315.18solution, at a concentration of 1 mg per mL in a mixture of [866-82-0]—Use a suitable grade.chloroform and ethanol (9:1). Cupric Nitrate [3251-23-8]—Use ACS reagent grade Cu-

Absorptivity—Its absorptivity at 275 nm, in alcohol solu- pric Nitrate Hydrate.tion, is about 1700. Cupric Nitrate Hydrate, Cu(NO3)2 · 2.5H2O—232.59

Collagen—Use a suitable grade. [3252-23-8]; Cu(NO3)2 · 3H2O—241.60 [10031-43-3]—Use[NOTE—A suitable grade is acid-soluble Collagen Type I ACS reagent grade.

from calf skin, and is commercially available from Sigma- [NOTE—This reagent is available containing either 2.5 or 3Aldrich Corp., www.sigma-aldrich.com; catalog number molecules of water of hydration.]C3511.] Cupric Sulfate, CuSO4 · 5H2O—249.69—Use ACS reagent

Rat Tail Collagen—Use a suitable grade. grade.[NOTE—A suitable grade is available from BD Biosciences, Cupric Sulfate, Anhydrous, CuSO4—159.61

www.bdbiosciences.com.] [7758-98-7]—A white or grayish-white powder free from aCollagenase—Use a suitable grade. blue tinge. Upon the addition of a small quantity of water,[NOTE—A suitable grade is commercially available as Col- it becomes blue. Soluble in water. Store in tight containers.

lagenase Type 2, CLS-2, from Worthington Biochemical Chloride (Reagent test)—One g shows not more thanCorp., www.worthington-biochem.com.] 0.02 mg of Cl (0.002%).

Compactin, C23H34O5—390.52 [73573-88-3]—Use a Substances not precipitated by hydrogen sulfide—Deter-suitable grade. mine as directed for ACS reagent grade of Cupric Acetate:[NOTE—A suitable grade is available from Sigma-Aldrich, the residue weighs not more than 6 mg (0.15%).www.sigma-aldrich.com.] Cupriethylenediamine Hydroxide Solution, 1.0 M—UseCongo Red, C32H22N6Na2O6S2—696.67 [573-58-0]—A a suitable grade.dark red or reddish-brown powder. Decomposes on expo- [NOTE—A suitable grade is available from GFS Chemicals,sure to acid fumes. Its solutions have a pH of about 8 to www.gfschemicals.com.]9.5. One g dissolves in about 30 mL of water. Is slightly Cyanoacetic Acid, C3H3NO2—85.06 [372-09-8]—soluble in alcohol. White to light yellow, crystalline solid. Very soluble in water.Loss on drying ⟨731⟩—Dry it at 105° for 4 hours: it loses Assay—Dissolve about 300 mg, accurately weighed, innot more than 3.0% of its weight. 25 mL of water and 25 mL of alcohol. Titrate with 0.1 NResidue on ignition—Accurately weigh about 1 g, previ- sodium hydroxide VS, determining the endpoint potentio-

ously dried at 105° for 4 hours, and place it in a porcelain metrically. Perform a blank determination and make anydish or crucible. Carefully ignite until well charred, cool, add necessary corrections. Each mL of 0.1 N sodium hydroxide2 mL of sulfuric acid, and carefully ignite until the residue is is equivalent to 85.06 mg of C3H3NO2. Not less than 99% iswhite or practically so. Cool, add 0.5 mL of sulfuric acid and found.1 mL of nitric acid, evaporate, and again ignite to constant Cyanogen Bromide, BrCN—105.92 [506-68-3]—Col-weight: the weight of the sodium sulfate so obtained is be- orless crystals. Volatilizes at room temperature. Its vapors aretween 20.0% and 24.0% of the weight of the dried speci- highly irritating and very toxic. Melts at about 52°. Freelymen taken. soluble in water and in alcohol. Store in tight containers in

Sensitiveness—To 50 mL of carbon dioxide-free water add a cold place.0.1 mL of congo red solution (1 in 1000). The red color of Solubility—Separate 1-g portions dissolve completely inthe solution is changed to violet by the addition of 0.05 mL 10 mL of water and in 10 mL of alcohol, respectively, toof 0.10 N hydrochloric acid and is restored by the subse- yield colorless solutions.quent addition of 0.05 mL of 0.10 N sodium hydroxide. 4-Cyanophenol (4-Hydroxybenzonitrile), C6H4CNOH—

Coomassie Blue G-250 (Coomassie Brilliant Blue G-250, 119.12 [767-00-0]—Use 95 percent reagent.Serva Blue G), C47H48N3O7S2Na—854.0 [6104-58-1]—A Cyclam (1,4,8,11-Tetraazacyclotetradecane), C10H24N4—dark blue powder. Soluble in water. Use a suitable grade. 200.33 [295-37-4]—Use 98 percent reagent.Store between 15° and 30°. α-Cyclodextrin (Cyclomaltohexaose; Schardinger α-Dex-

Coomassie Brilliant Blue R-250, C45H44N3O7S2Na— trin), C36H60O30—972.86 [10016-20-3]—Use a suitable825.97 [6104-58-1]—Brown powder. grade with a content of not less than 98.0%.

Copper, Cu—At. Wt. 63.546 [7440-50-8]—Use ACS [NOTE—A suitable grade is available from Fluka, www.reagent grade. sigma-aldrich.com, catalog number 28705.]

Cortisone, C21H28O5—360.44 [53-06-5]—White, crys-talline powder. Practically insoluble in water; sparingly solu-


[NOTE—A suitable grade is available from either BD Biosci-Add the following:ences, www.bdbiosciences.com or Applied Biosystems,www.appliedbiosystems.com.]▲ β-Cyclodextrin (β-Schardinger dextrin;

Deuterated Methanol (Methanol-12C-d4, Methyl-12C-d3 al-Cycloheptaamylose), C42H70O35 · xH2O—1134.98 (anhy-cohol-d1)—36.1 [811-98-3]—The degree of deuteration isdrous) [68168-23-0]—Use a suitable hydrate grade.▲ USP36 not less than 99.8%. Is a clear colorless liquid miscible withCyclohexane, C6H12—84.16 [110-82-7]—Use ACS rea-water, with alcohol, and with methylene chloride; density atgent grade.20°: 0.888 g/mL; refractive index at 20° (D-line): 1.326;Cyclohexanol, C6H12O—100.16 [108-93-0]—A clearboiling point 65.4° (760 mm Hg).liquid. Freely soluble in water. Miscible with alcohol, with

Deuterated Water—See Deuterium Oxide.ethyl acetate, and with aromatic hydrocarbons.Deuterium Chloride (Deutero Hydrochloric Acid), DCl—Assay—When examined by gas-liquid chromatography, 37.47 [7698-05-7]—Toxic gas. Use a suitable grade with ausing suitable gas chromatographic apparatus and condi- degree of deuteration of NLT 99%.tions, it shows a purity of not less than 98%. Deuterium Oxide, D2O—20.032 [7789-20-0]—Use a

Melting temperature: about 23°. suitable grade having a minimum isotopic purity of 99.8Specific gravity: about 0.962, at 20°. atom % of deuterium.

(1,2-Cyclohexylenedinitrilo)tetraacetic Acid (trans-1, Deuterochloroform, CDCl3—120.38—Use a suitable2-Diaminocyclohexane-N,N,N′,N′-tetraacetic Acid), grade.C14H22N2O8 · H2O—364.35—Use ACS reagent grade. Devarda’s Alloy (Devarda’s Metal) [8049-11-4]—A gray

Cyclohexylmethanol, C7H14O—114.19—Use a suitable powder composed of 50 parts of copper, 45 parts of alumi-grade. num, and 5 parts of zinc.

L-Cystine, HOOC(NH2)CHCH2S—SCH2CH(NH2)COOH— Dextran, High Molecular Weight [9004-54-0]—A dex-240.30 [58-89-3]—A white, crystalline powder. Very tran molecular weight standard having a weight-averageslightly soluble in water; soluble in dilute mineral acids and molecular weight, MW, of 1 to 2 × 106 Da and a weight-in solutions of alkali hydroxides; insoluble in alcohol and in average molecular weight to number-average molecularother organic solvents. weight ratio, MW / MN, of 1.0 to 1.8.

[NOTE—A suitable grade is available from American Poly-Specific rotation ⟨781⟩: between −215° and −225°, de-mer Standards Corporation, www.ampolymer.com.]termined in a 2 in 100 solution of test specimen, previously

Dextrin, (C6H10O5)n · xH2O [9004-53-9]—A white amor-dried over silica gel for 4 hours, in dilute hydrochloric acidphous powder. Slowly soluble in cold water; more readily(1 in 10) at a temperature of 20°.soluble in hot water; insoluble in alcohol.Loss on drying ⟨731⟩—Dry it over silica gel for 4 hours: it

Insoluble matter—Boil 1 g with 30 mL of water in a smallloses not more than 0.2% of its weight.flask: the solution is colorless and clear, or not more thanResidue on ignition (Reagent test): not more than 0.1%. opalescent.DEAE-Agarose [57407-08-6]—Agarose beads chemically

Loss on drying ⟨731⟩—Dry it at 105° to constant weight:bonded with diethylaminoethane and suspended in a 20%it loses not more than 10.0% of its weight.ethanol solution in water.

[NOTE—Commercially available as DEAE-Sepharose.] Residue on ignition (Reagent test)—Ignite 1 g with 0.5 mLDecanol (n-Decyl Alcohol), C10H22O—158.28 of sulfuric acid: the residue weighs not more than 5 mg

[112-30-1]—A clear, viscous liquid. Specific gravity: about (0.5%).0.83 at 20°. Solidifies at about 6.5°. Insoluble in water; solu- Chloride (Reagent test)—Dissolve 3 g in 75 mL of boilingble in alcohol and in ether. water, cool, dilute with water to 75 mL, and filter if neces-

Assay—When examined by gas-liquid chromatography, sary. To 25 mL of the filtrate add 2 mL of nitric acid andusing suitable gas chromatographic apparatus and condi- 1 mL of silver nitrate TS, and allow to stand for 5 minutes:tions, it shows a purity of not less than 99%. any turbidity produced is not greater than that of a control

Decyl Sodium Sulfate, C10H21NaO4S—260.33—White, containing 0.02 mg of added Cl (0.002%).crystalline solid. Sulfate (Reagent test, Method I)—To a 25-mL portion of

Assay—Transfer about 1 g, accurately weighed, to a suita- the filtrate from the preceding test add 0.5 mL of dilutedble, tared crucible, moisten with a few drops of sulfuric acid, hydrochloric acid and 2 mL of barium chloride TS, and allowand ignite gently to constant weight. Each mg of residue is to stand for 10 minutes: any turbidity produced is notequivalent to 3.662 mg of C10H21NaO4S. Not less than 95% greater than that of a control containing 0.2 mg of addedis found. SO4 (0.02%).

Dehydrated Alcohol—See Alcohol, Dehydrated. Alcohol-soluble substances—Boil 1 g with 20 mL of alcoholDeoxyadenosine Triphosphate, C10H16N5O12P3—491.18 for 5 minutes under a reflux condenser, and filter while hot.

[1927-31-7]—Use a suitable grade. Evaporate 10 mL of the filtrate on a steam bath, and dry at[NOTE—A suitable grade is available from either BD Bio- 105°: the residue weighs not more than 5 mg (1%).

sciences, www.bdbiosciences.com or Applied Biosystems, Reducing sugars—Shake 2 g with 100 mL of water forwww.appliedbiosystems.com.] 10 minutes, and filter until clear. To 50 mL of the filtrateDeoxycytidine Triphosphate, C9H16N3O13P3—467.16 add 50 mL of alkaline cupric tartrate TS, and boil for 3 min-[2056-98-6]—Use a suitable grade. utes. Filter through a tared filtering crucible, wash with[NOTE—A suitable grade is available from either BD Biosci- water, then with alcohol, and finally with ether, and dry atences, www.bdbiosciences.com or Applied Biosystems, 105° for 2 hours: the precipitate of cuprous oxide weighswww.appliedbiosystems.com.] not more than 115 mg (corresponding to about 5% of re-Deoxyguanosine Triphosphate, C10H16N5O13P3—507.18 ducing sugars as dextrose).[2564-35-4]—Use a suitable grade. Dextro Calcium Pantothenate—Use Calcium Pantothen-[NOTE—A suitable grade is available from either BD Biosci- ate (USP monograph).ences, www.bdbiosciences.com, or Applied Biosystems, Dextrose, Anhydrous, C6H12O6—180.16—Use ACS rea-www.appliedbiosystems.com.] gent grade D-Glucose, Anhydrous.Deoxyribonucleic Acid Polymerase—Thermostable, re- Diacetyl—See 2,3-Butanedione.combinant DNA polymerase. Use a suitable grade. 3,3′-Diaminobenzidine Hydrochloride,[NOTE—A suitable grade is available from Applied Biosys- (NH2)2C6H3C6H3(NH2)2 · 4HCl—360.11 [7411-49-6]—tems, www.appliedbiosystems.com.] White to yellowish-tan (occasionally purple), needle-shapedDeoxythymidine Triphosphate, C10H17N2O14P3— crystals. Soluble in water. Stable in organic solvents but un-482.17—Use a suitable grade.


stable in aqueous solution at room temperature. Store aque- (made by dissolving 2.84 g of crystallized sodium borate inous solutions in a refrigerator. 90 mL of warm water, adding 8.2 mL of 1 N sodium hy-

droxide, and diluting with water to 100 mL) and 0.1 mL ofInsoluble matter—Dissolve 2 g in 100 mL of water, with-a solution of 10 mg of the test specimen in 20 mL of alco-out heating, and filter immediately: the insoluble residuehol: a distinct blue color develops within 10 minutes.does not exceed 1 mg (0.05%).

Dibutyl Phthalate, C16H22O4—278.34 [84-74-2]—Residue on ignition (Reagent test): not more than 1 mg, Clear, colorless liquid.from 2 g (0.05%).Assay—Accurately weigh about 2 g into a suitable flask,Suitability test for detection of selenium—Dissolve 1.633 g add 25.0 mL of 1 N sodium hydroxide and 30 mL of isopro-of selenious acid (H2SeO3) in water, and dilute with water to pyl alcohol, and mix. Digest the mixture at a temperature1 L. Dilute 10 mL of this solution with water to 1 L, to make near boiling for 30 minutes, then cool in a water bath toa solution containing 0.010 mg of Se per mL. Place 1 mL of room temperature. Add phenolphthalein TS, and titrate withthe resulting solution in a 100-mL beaker, add 2 mL of for- 1 N sulfuric acid VS to the disappearance of the pink color.mic acid solution (1 in 7), and dilute with water to 50 mL. Perform a complete blank determination, and make anyAdd 2 mL of 3,3′-diaminobenzidine hydrochloride solution necessary correction. Each mL of 1 N sulfuric acid consumed(1 in 200), and allow to stand for 30 to 50 minutes. Adjust is equivalent to 139.2 mg of C16H22O4. Not less than 98% iswith 6 N ammonium hydroxide to a pH between 6 and 7. found.Transfer to a 125-mL separator, add 10.0 mL of toluene, andRefractive index ⟨831⟩: between 1.491 and 1.493 at 20°.shake vigorously for 30 seconds: a distinct yellow color is

produced in the toluene layer. A blank containing diami- Acid content—Accurately weigh about 10 g, and dissolvenobenzidine hydrochloride but no selenium standard, in 100 mL of an alcohol-ether mixture (1:1). Add phenol-treated in the same manner, shows no color in the toluene phthalein TS, and titrate immediately with 0.05 N alcoholiclayer. potassium hydroxide VS. Each mL of 0.05 N alcoholic potas-

2,3-Diaminonaphthalene, C10H10N2—158.20 sium hydroxide is equivalent to 4.15 mg of phthalic acid:[771-97-1]—Use a suitable grade. not more than 0.02% is found.

Diatomaceous Earth [91053-39-3]—Use a suitable grade. Dibutylamine, C8H19N—129.24 [111-92-2]—Colorless[NOTE—A suitable grade is available as Celite 545-AW.] liquid.

Diatomaceous Earth, Flux-Calcined [91053-39-3]—Use a Assay—Inject an appropriate volume into a gas chromat-suitable grade. ograph (see Chromatography ⟨621⟩) equipped with a flame-

[NOTE—A suitable grade is “Chromosorb W, AW-DMCS,” ionization detector, helium being used as the carrier gas.available from Grace, www.grace.com.] The following conditions have been found suitable: a 0.25-

Diatomaceous Earth, Silanized [91053-39-3]—Use a suit- mm × 30-m capillary column coated with a 1-µm layer ofable grade. phase G2; the injection port temperature is maintained at

[NOTE—Suitable grades are available commercially as 200°; the detector temperature is maintained at 300°; and“Anachrome Q,” “Gas-Chrom Q,” and “Varaport 30.”] the column temperature is maintained at 100° and pro-

Diatomaceous Silica, Calcined [68855-54-9]—A form of grammed to rise 10° per minute to 200°. The area of thesilica (SiO2) consisting of fused frustules and fragments of C8H19N peak is not less than 99% of the total peak area.diatoms. It is an amorphous, fine, light pink or white pow- Refractive index ⟨831⟩: between 1.415 and 1.419 atder. Insoluble in water, in acids, and in dilute solutions of 20°.alkali hydroxides. Dibutylammonium Phosphate—Use a suitable grade.

Loss on ignition—Accurately weigh about 4 g, and ignite [NOTE—A suitable grade is available as PIC Reagent D4to constant weight: it loses not more than 10.0% of its from Waters Corporation, www.waters.com.]weight. 1,3-Dicaffeoylquinic Acid (Cynarin; (1R,3R,4S,5R)-1,3-Bis

Organic impurities—It does not darken appreciably upon [[3-(3,4-dihydroxyphenyl)propenoyl]oxy]-4,5-ignition. dihydroxycyclohexanecarboxylic Acid), C25H24O12—516.45

[30964-13-7]—Use a suitable grade. Loss on drying ⟨731⟩—Dry it at 110° for 2 hours: it loses[NOTE— A suitable grade is available as catalog numbernot more than 2.0% of its weight.

3991 from www.chromadex.com.][NOTE—Suitable grades are “Chromosorb P” andDichloroacetic Acid, C2H2Cl2O2—128.9 [79-43-6]—“Chromosorb W,” available from Grace, www.grace.com.]

Colorless liquid. Miscible with water, with alcohol, and withDiaveridine (5-([3,4-Dimethoxyphenyl]methyl)-2,4-ether. Use a suitable grade.pyrimidinediamine), C13H16N4O2—260.3 [5355-16-8]—Use

2,5-Dichloroaniline, Cl2C6H3NH2—162.02 [95-82-9]—a suitable grade. [NOTE—A suitable grade is available as cat-White, needle-like crystals. Slightly soluble in water; solublealog number 46174 from www.sigma-aldrich.com.]in alcohol and in ether.Dibasic Ammonium Citrate—See Ammonium Citrate, Di-

basic. Melting range, Class I ⟨741⟩: between 49° and 50°.Dibasic Ammonium Phosphate—See Ammonium Phos- 2,6-Dichloroaniline, C6H5Cl2N—162.02 [608-31-1]—

phate, Dibasic. Off-white powder.Dibasic Potassium Phosphate—See Potassium Phosphate, Melting range ⟨741⟩: between 38° and 41°.

Dibasic. o-Dichlorobenzene, C6H4Cl2—147.00 [95-50-1]—ClearDibenzyl—See Bibenzyl. liquid, having a light yellowish-brown tint (about APHA 20).2,6-Dibromoquinone-chlorimide (2,6-Dibromo-N-chloro- Practically insoluble in water. Miscible with alcohol and with

p-benzoquinone Imine; DBQ Reagent), O:C6H2Br2:NCl— ether. Boils at about 180°.299.35 [537-45-1]—A yellow, crystalline powder. Insolu- Assay—When examined by gas–liquid chromatography,ble in water; soluble in alcohol and in dilute alkali hydroxide with the use of suitable apparatus and conditions, it shows asolutions. purity of not less than 98%.

Melting range ⟨741⟩: between 82° and 84°. Density: between 1.299 and 1.301.Solubility in alcohol—A solution of 100 mg in 10 mL of Refractive index ⟨831⟩: between 1.548 and 1.550 atalcohol is not more than faintly turbid. 25°.Residue on ignition (Reagent test)—Ignite 500 mg with Residue on evaporation—Evaporate 80 mL on a steam0.5 mL of sulfuric acid: the residue weighs not more than bath, and dry at 105° for 1 hour: the residue weighs not1 mg (0.2%). more than 50 mg (0.005%).Sensitiveness—To 10 mL of a water solution containing Acidity—Add phenolphthalein TS to 25 mL of methanol,0.01 mg of phenol add 0.3 mL of a sodium borate buffer and titrate with 0.02 N alcoholic potassium hydroxide VS


until a faint pink color persists for 15 seconds. Pipet 25 mL crystalline powder. Insoluble in water; soluble in alcohol andof test specimen into the solution; mix, avoiding exposure in dilute alkali hydroxide solutions.to the atmosphere; and titrate with 0.02 N alcoholic potas- Melting range ⟨741⟩: between 65° and 67°.sium hydroxide VS: not more than 2.2 mL is required to Solubility in alcohol—A solution of 100 mg in 10 mL ofrestore the pink color (about 0.005%). alcohol is complete and clear.1,2-Dichloroethane—See Ethylene Dichloride.

Residue on ignition—Ignite 500 mg with 0.5 mL of sulfuricDichlorofluorescein, C20H10Cl2O5—401.20 [76-54-0]—acid: the residue weighs not more than 1 mg (0.2%).[NOTE—This specification covers both the 4,5- and 2,7-iso-

Sensitiveness—It meets the requirements of the test formers of dichlorofluorescein, either of which is suitable forSensitiveness under 2,6-Dibromoquinone-chlorimide.the preparation of dichlorofluorescein TS.] A weak orange-

Dicyclohexyl, (Bicyclohexyl) C12H22—166.31colored, crystalline powder. Sparingly soluble in water; solu-[92-51-3]—Use a suitable grade.ble in alcohol and in solutions of alkali hydroxides.

Dicyclohexyl Phthalate, C20H26O4—330.42 [84-61-7].Residue on ignition (Reagent test)—Ignite 200 mg withMelting range ⟨741⟩: between 62° and 66°.5 drops of sulfuric acid: the residue weighs not more than

Dicyclohexylamine, (C6H11)2NH—181.32 [101-83-7]—1 mg (0.5%).Clear, strongly alkaline liquid. Sparingly soluble in water.Sensitiveness—Dissolve 100 mg in 60 mL of alcohol, addMiscible with common organic solvents. Use a suitable2.5 mL of 0.1 N sodium hydroxide, and dilute with water tograde with a content of not less than 98%.100 mL. Add 1 mL of this solution to a solution of potas-

Diethylamine, (C2H5)2NH—73.14 [109-89-7]—Color-sium iodide prepared by dissolving 100 mg of potassium io-less, flammable, strongly alkaline liquid. Miscible with waterdide, previously dried at 105° to constant weight and accu-and with alcohol. Forms a hydrate with water. May be irri-rately weighed, in 50 mL of water containing 1 mL of glacialtating to skin and mucous membranes. Store in well-closedacetic acid, and titrate with 0.1 N silver nitrate VS until thecontainers. Use ACS reagent grade.color of the precipitate changes from pale yellowish-orange

Diethylamine Phosphate (Phosphoric Acid: Diethyl-to pink. The volume of 0.1 N silver nitrate consumed is notamine), C4H11N · H3PO4—171.13 [68109-72-8]—Use amore than 0.10 mL greater than the calculated volume, thesuitable grade. [NOTE—A suitable grade is available fromcalculated volume being based upon the KI content of thewww.richmanchemical.com.]dried specimen as determined in the Assay under Potassium

N,N-Diethylaniline, C6H5N(C2H5)2—149.23 [91-66-7]—Iodide (USP monograph).Light yellow to amber liquid.Dichlorofluoromethane, CHCl2F—102.92 [75-43-4]—

Assay—Inject an appropriate specimen (about 0.2 µL)Colorless gas.into a suitable gas chromatograph (see ChromatographyAssay—Inject an appropriate specimen into a gas chro-⟨621⟩) equipped with a flame-ionization detector, heliummatograph (see Chromatography ⟨621⟩) equipped with abeing used as the carrier gas flowing at about 40 mL perthermal-conductivity detector, helium being used as the car-minute. The following conditions have been found suitable:rier gas. The following conditions have been found suitable:a 3-mm × 1.8-m stainless steel column containing 20%a 0.53-mm × 30-m capillary column coated with a 5-µmphase G16 on support S1A; the injection port temperaturelayer of phase G2; the injection port temperature is main-is maintained at 250°; the column temperature is main-tained at 200°; the detector temperature is maintained attained at 140° and programmed to rise 6° per minute to200°; and the column temperature is maintained at 0° and200°. The detector temperature is maintained at 310°. Theprogrammed to rise 5° per minute to 40°, and then to risearea of the N,N-diethylaniline peak having a retention time10° per minute to 180°. The area of the CHCl2F peak is notof about 4.9 minutes is not less than 99% of the total peakless than 98% of the total peak area.area.2,6-Dichloroindophenol Sodium—See 2,6-Dichlorophe-

Refractive index ⟨831⟩: between 1.5405 and 1.5425 atnol-indophenol Sodium.20°.Dichloromethane—Use Methylene Chloride.

Diethylene Glycol, (Bis(2-hydroxyethyl) Ether; Diglycol;2,4-Dichloro-1-naphthol, C10H6OCl2—213.062-Hydroxyethyl Ether; 2,2′-Oxydiethanol), C4H10O3—106.12[2050-76-2]—Light tan powder.[111-46-6]—A colorless to faintly yellow, viscous, hygro-Melting range ⟨741⟩: between 103° and 107°, but thescopic liquid. Miscible with water, with alcohol, with ether,range between beginning and end of melting does not ex-and with acetone. Insoluble in benzene and in carbon tetra-ceed 2°.chloride. Use a suitable grade with a content of not less2,6-Dichlorophenol-indophenol Sodium (2,6-Dichloro-in-than 99.0%.dophenol Sodium), O:C6H2Cl2:NC6H4ONa with about 2H2O—

Di(ethylene glycol) Methyl Ether (2-(2-Methoxyeth-290.08 (anhydrous) [620-45-1] —Use ACS reagent grade.oxy)ethanol; Methyldiglycol), C5H12O3—120.152,6-Dichlorophenylacetic Acid, C8H6Cl2O2—205.04[111-77-3]—Use a suitable grade.[6575-24-2]—White powder.

Diethylene Glycol Succinate Polyester,Assay—Inject an appropriate specimen into a gas chro- (OCH2CH2OCH2CH2OOCCH2CH2COO)n [26183-02-8]—matograph (see Chromatography ⟨621⟩) equipped with a Clear, viscous liquid. Soluble in chloroform. Is stabilized byflame-ionization detector, helium being used as the carrier modification of the diethylene glycol succinate polyester, togas. The following conditions have been found suitable: a render it suitable for use in gas–liquid chromatography to a0.25-mm × 30-m capillary column coated with a 1-µm layer temperature of 200°.of phase G2; the injection port temperature is maintained at250°; the detector temperature is maintained at 300°; andthe column temperature is maintained at 150° and pro-grammed to rise 10° per minute to 280°. The area of theC8H6Cl2O2 peak is not less than 97% of the total peak area.

2,6-Dichloroquinone-chlorimide (2,6-Dichloro-N-chloro-p-benzoquinone Imine), O:C6H2Cl2:NCl—210.44—Pale yellow,


[NOTE—A suitable grade is available from Alltech, www. any necessary correction. Each mL of 0.1 N sodium hydrox-alltechweb.com.] ide is equivalent to 15.41 mg of C7H6O4. Not less than 99%

Diethylenetriamine, C4H13N3—103.17 [111-40-0]— is found.Colorless liquid. Melting range ⟨741⟩: about 207°, with decomposition.

Assay—Inject an appropriate specimen into a suitable gas 2,7-Dihydroxynaphthalene—See 2,7-Naphthalenediol.chromatograph (see Chromatography ⟨621⟩) equipped with Diiodofluorescein, C20H10I2O5—584.10 [31395-16-1]—a flame-ionization detector, helium being used as the carrier Orange-red powder. Slightly soluble in water; soluble in al-gas. The following conditions have been found suitable: a cohol and in solutions of alkali hydroxides.0.25-mm × 30-m capillary column coated with G2. The in- Residue on ignition—Ignite 200 mg with 5 drops of sulfu-jection port temperature is maintained at 200°; the column ric acid: the weight of the residue does not exceed 1.0 mgtemperature is maintained at 100° and programmed to rise (0.5%).10° per minute to 250° and held there for 5 minutes; and Sensitiveness—Accurately weigh about 100 mg of potas-the detector temperature is maintained at 300°. The area of sium iodide, previously dried at 105° to constant weight,the main peak is not less than 95% of the total peak area. and dissolve it in 50 mL of water. Add 1 mL of

Refractive index ⟨831⟩: between 1.4815 and 1.4845 at diiodofluorescein TS prepared from the test specimen and20°. 1 mL of glacial acetic acid, and titrate with 0.1 N silver ni-

Di(2-ethylhexyl)phthalate [Bis(2-ethylhexyl)phthalate], trate VS until the color of the precipitate changes fromC24H38O4—390.56 [117-81-7]—Use a suitable grade. brownish-red to a bluish-red. The volume of 0.1 N silver

Diethylpyrocarbonate, C6H10O5—162.14 nitrate consumed is not in excess of 0.10 mL over the calcu-[1609-47-8]—Clear, colorless liquid. Use a suitable grade. lated volume, based on the KI content of the dried potas-

Diethyl Sulfone (Ethyl Sulfone), (C2H5)2SO2—122.19 sium iodide determined as follows. Dissolve about 500 mg[597-35-3]—Use a suitable grade with NLT 97%. of potassium iodide, accurately weighed, in about 10 mL of

Digitonin, C56H92O29—1229.31 [11024-24-1]—White, water, and add 35 mL of hydrochloric acid and 5 mL ofcrystalline powder. Almost insoluble in water; soluble in chloroform. Titrate with 0.05 M potassium iodate VS untilwarm alcohol, and in glacial acetic acid and in 75% acetic the purple color of iodine disappears from the chloroform.acid; insoluble in chloroform and in ether. Melts at about Add the last portions of the iodate solution dropwise, agitat-230°, with decomposition. ing vigorously and continuously. After the chloroform has

Specific rotation ⟨781⟩: between −47° and −49°, deter- been decolorized, allow the mixture to stand for 5 minutes.mined in a solution in 75% acetic acid containing 100 mg If the chloroform develops a purple color, titrate furtherper mL. with the iodate solution. Each mL of 0.05 M potassium io-

date is equivalent to 16.60 mg of KI.Solubility in alcohol—A solution of 500 mg in 20 mL ofDiisodecyl Phthalate [Bis(isodecyl)phthalate], C28H46O4—warm alcohol is colorless and complete.

446.66 [26761-40-0]—Use a suitable grade.Loss on drying ⟨731⟩—Dry it at 105° to constant weight: Diisopropyl Ether (Isopropyl Ether), [(CH3)2CH]2O—it loses not more than 6% of its weight. 102.17 [108-20-3]—Colorless, mobile liquid. Slightly sol-Residue on ignition (Reagent test): not more than 0.3%. uble in water. Miscible with alcohol and with ether.

Digoxigenin (3β,12β,14β,21-Tetrahydroxy-20(22)- [CAUTION—It is highly flammable. Do not use where it maynorcholenic Acid Lactone; 3β,12β,14-Trihydroxy-5β,20(22)- be ignited. Do not evaporate to the point of near dryness,cardenolide; 5β,20(22)-Cardenolide-3β,12β,14-triol; since it tends to form explosive peroxides.]Lanadigenin), C23H34O5—390.51 [1672-46-4]—Use a suita- Specific gravity: between 0.716 and 0.720.ble grade.

Distilling range, Method II ⟨721⟩—Not less than 95% dis-Dihydroquinidine Hydrochloride, C20H27ClN2O2—362.89tills between 65° and 70°.[1476-98-8]—Rhombic plates. Freely soluble in methanol

and in chloroform. Peroxides—To 10 mL, contained in a clean, glass-stop-pered cylinder previously rinsed with a portion of the etherAssay—under examination, add 1 mL of freshly prepared potassiumMOBILE PHASE—Prepare a mixture of water, acetonitrile, di- iodide solution (1 in 10). Shake, and allow to stand forethylamine, and methanesulfonic acid (860:100:20:20). 1 minute: no yellow color is observed in either layer (about

PROCEDURE—Inject about 20 µL into a suitable liquid chro- 0.001% as H2O2).matograph (see Chromatography ⟨621⟩) equipped with a Residue on evaporation—[NOTE—If peroxide is present, do235-nm detector and a 4.6-mm × 15-cm column that con- not carry out this procedure.] Evaporate 14 mL (10 g) from atains packing L1. The flow rate is about 1.5 mL per minute. tared shallow dish, and dry at 105° for 1 hour: the residueThe area of the C20H27ClN2O2 peak is not less than 97.5% of weighs not more than 1 mg (0.01%).the total peak area.Acidity—Add 2 drops of bromothymol blue TS to 10 mLDihydroquinine (Hydroquinine), C20H26N2O2—326.43

of water in a glass-stoppered, 50-mL flask, and titrate with[522-66-7]—Freely soluble in acetone, in alcohol, and in0.010 N sodium hydroxide until a blue color persists afterchloroform; almost insoluble in water.vigorous shaking. Add 5 mL of diisopropyl ether, and titrateAssay— with 0.010 N sodium hydroxide: not more than 0.30 mL is

MOBILE PHASE—Prepare a mixture of water, acetonitrile, di- required to restore the blue color (0.005% as CH3COOH).ethylamine, and methanesulfonic acid (860:100:20:20) and [NOTE—For spectrophotometric determinations, use di-methanol (82:18). isopropyl ether that meets the following additional

PROCEDURE—Inject about 20 µL into a suitable liquid chro- requirement:]matograph (see Chromatography ⟨621⟩) equipped with a Absorbance—Its absorbance at 255 nm, in a 10-mm235-nm detector and a 4.6-mm × 15-cm column that con- quartz cell, does not exceed 0.2, water being used as thetains packing L1. The flow rate is about 1.5 mL per minute. blank.The area of the C20H26N2O2 peak is not less than 97.5% of Diisopropylamine, [(CH3)2CH]2NH—101.19the total peak area. [108-18-9]—Colorless liquid.

2,5-Dihydroxybenzoic Acid, C7H6O4—154.12 Assay—Not less than 98% of C6H15N is found, a suitable[303-07-1]—Off-white powder. Freely soluble in alcohol gas chromatograph equipped with a flame-ionization detec-yielding a clear, very pale yellow solution. tor being used. The following conditions have been foundAssay—Dissolve about 75 mg, accurately weighed, in suitable: a 3.2-mm × 1.83-m stainless steel column is

30 mL of methanol. Slowly add 40 mL of water. Titrate with packed with a cross-linked polystyrene support; the injection0.1 N sodium hydroxide VS, determining the endpoint po- port temperature is maintained at 250° and the detectortentiometrically. Perform a blank determination, and make


temperature at 310°; the column temperature is pro- The area of the dimethyl phthalate peak is not less thangrammed to rise at 10° per minute from 50° to 220°. 99% of the total peak area.

Refractive index ⟨831⟩: between 1.3915 and 1.3935, at Refractive index ⟨831⟩: between 1.514 and 1.518 at 20°.20°. Dimethyl Sulfone (Methyl Sulfone), (CH3)2SO2—94.13

Diisopropylethylamine (N,N-Diisopropylethylamine), [67-71-0]—White crystals.C8H19N—129.24 [7087-68-5]—Clear, colorless liquid. Sol- Melting range ⟨741⟩: between 109° and 111°.uble in glacial acetic acid. Dimethyl Sulfoxide (Methyl Sulfoxide), (CH3)2SO—

Assay—Accurately weigh about 500 mg, dissolve in 78.13—Use ACS reagent grade methyl sulfoxide.50 mL of glacial acetic acid, mix, add crystal violet TS, and Dimethyl Sulfoxide, Spectrophotometric Gradetitrate with 0.1 N perchloric acid VS. Each mL of 0.1 N [67-68-5]—Use methyl sulfoxide ACS spectrophotometric re-perchloric acid is equivalent to 12.92 mg of C8H19N. Not agent grade.less than 98% is found. N,N-Dimethylacetamide, C4H9NO—87.12

[127-19-5]—Clear, colorless liquid. Miscible with water andRefractive index ⟨831⟩: between 1.4125 and 1.4145 atwith many organic solvents. Use a suitable HPLC or spectro-20°.scopic grade.1,2-Dilinoleoyl-3-oleoyl-rac-glycerol, C57H100O6—881.4

p-Dimethylaminoazobenzene (Methyl Yellow, Butter Yel-[2190-21-8]—Use a suitable grade.low), C6H5N:NC6H4N(CH3)2—225.29 [60-11-7]—Yellow1,2-Dilinoleoyl-3-palmitoyl-rac-glycerol, C55H98O6—leaflets or yellow, crystalline powder.855.4 [2190-15-0]—Use a suitable grade.

Diluted Acetic Acid—See Acetic Acid, Diluted. Solubility—Insoluble in water; sparingly soluble in chloro-Diluted Alcohol—Use Diluted Alcohol (NF monograph). form, in ether, or in fatty oils. Dissolve 100 mg in 20 mL ofDiluted Hydrochloric Acid—See Hydrochloric Acid, Di- alcohol: the solution is complete or practically so and clear.

luted. Melting range ⟨741⟩: between 115° and 117°.Diluted Nitric Acid—See Nitric Acid, Diluted. Residue on ignition ⟨281⟩: not more than 0.1%.Diluted Sulfuric Acid—See Sulfuric Acid, Diluted.

Sensitiveness—Add 0.05 mL of an alcohol solution (1 inDimethicone, viscosity 500 centistokes (Poly(dimethyl-200) and 2 g of ammonium chloride to 25 mL of carbonsiloxane), viscosity 500 centistokes), [–Si(CH3)2O–]n dioxide-free water: the lemon-yellow color of the solution is[63148-62-9]—Use a suitable grade.changed to orange by the addition of 0.05 mL of 0.1 N2,5-Dimethoxybenzaldehyde, C9H10O3—166.17hydrochloric acid and restored on the subsequent addition[93-02-7]—Off-white crystals.of 0.05 mL of 0.1 N sodium hydroxide.Assay—Inject an appropriate specimen into a suitable gas p-Dimethylaminobenzaldehyde,chromatograph (see Chromatography ⟨621⟩) equipped with (CH3)2NC6H4CHO—149.19 [100-10-7]—Use ACS reagenta flame-ionization detector, nitrogen being used as the car- grade.rier gas. The following conditions have been found suitable: p-Dimethylaminocinnamaldehyde,a 0.3-mm × 30-m capillary column coated with phase G1; (CH3)2NC6H4CH:CHCHO—175.23—Orange-yellow powder.the injection port temperature is maintained at 270°; the Soluble in acetone, in alcohol, and in benzene.detector temperature is maintained at 300°; the column

Melting range ⟨741⟩: between 132° and 136°.temperature is maintained at 150° and programmed to rise2-Dimethylaminoethyl Methacrylate, C8H15NO2——10° per minute to 270°. The area of the main peak is not

157.2 [2867-47-2]—Use a suitable grade.less than 97% of the total peak area.Dimethylaminophenol (meta isomer), C8H11NO—Melting range ⟨741⟩: between 50° and 52°. 137.18—Purplish–black, gray, or tan-colored, crystalline1,2-Dimethoxyethane, C4H10O2—90.12 [110-71-4]— solid.Clear, colorless liquid. Miscible with water and with alcohol.Melting range ⟨741⟩: between 83° and 85°.Soluble in hydrocarbon solvents. May form peroxides on

2,6-Dimethylaniline, C8H11N—121.18 [87-62-7]—Yel-standing.low liquid.Boiling range (Reagent test)—Not less than 95% distills

Refractive index ⟨831⟩: about 1.5609 at 20°.between 83° and 86°.N,N-Dimethylaniline, C6H5N(CH3)2—121.18Refractive index ⟨831⟩: between 1.379 and 1.381, at [121-69-7]—Light yellow liquid. Clear, colorless liquid when20°. freshly distilled, but acquiring a reddish to reddish-brown

Acidity—To 20 mL add bromophenol blue TS, and titrate color. Specific gravity: about 0.960. Freezing point about 2°.with 0.020 N sodium hydroxide: not more than 2.0 mL is Insoluble in water; soluble in alcohol, in chloroform, inconsumed (about 0.015% as CH3COOH). ether, and in dilute mineral acids.

Water, Method I ⟨921⟩: not more than 0.2%. Assay—Inject an appropriate specimen (about 0.2 µL)Dimethoxymethane (Formaldehyde Dimethyl Acetal, Meth- into a suitable gas chromatograph (see Chromatography

ylal), C3H8O2—76.10 [109-87-5]—Use a suitable grade. ⟨621⟩) equipped with a flame-ionization detector, helium(3,4-Dimethoxyphenyl)acetonitrile (Homoveratronitrile), being used as the carrier gas flowing at about 40 mL per

C10H11NO2—177.20 [93-17-4]—Off-white fibers. minute. The following conditions have been found suitable:Melting range ⟨741⟩: between 65° and 67°. a 3-mm × 1.8-m stainless steel column containing 20%

Dimethyl Phthalate, C10H10O4—194.19 [131-11-3]— phase G16 on support S1A; the injection port temperatureViscous, colorless liquid. is maintained at 250°; the column temperature is main-

tained at 50° and programmed to rise 10° per minute toAssay—200°. The detector temperature is maintained at 310°. TheMOBILE PHASE—Prepare a filtered and degassed mixture ofarea of the N,N-dimethylaniline peak having a retentionchromatographic n-heptane and n-propyl alcohol (HPLCtime of about 11.5 minutes is not less than 99% of the totalgrade) (97:3). Make adjustments if necessary (see Systempeak area.Suitability under Chromatography ⟨621⟩).

STANDARD SOLUTION—Dissolve a suitable quantity of di- Refractive index ⟨831⟩: between 1.5571 and 1.5591 atmethyl phthalate in Mobile phase to obtain a solution having 20°.a known concentration of about 0.26 mg per mL. Boiling range (Reagent test)—Distill 100 mL: the differ-

PROCEDURE—Inject about 20 µL into a suitable liquid chro- ence between the temperatures observed, when 1 mL andmatograph (see Chromatography ⟨621⟩) equipped with a 95 mL have distilled, is not more than 2.5°. Its boiling tem-238-nm detector and a 4.6-mm × 25-cm column that con- perature at a pressure of 760 mm of mercury is 194.2°.tains packing L10. The flow rate is about 1.0 mL per minute.


Hydrocarbons—Dissolve 5 mL in a mixture of 10 mL of Sulfanilamide test—Dissolve 20 mg of USP Sulfanilamidehydrochloric acid and 15 mL of water: a clear solution re- RS in 100 mL of water to obtain the Sulfanilamide solution.sults and it remains clear on cooling to about 10°. Into two 150-mL beakers pipet 1.0 mL and 2.5 mL of the

Sulfanilamide solution, respectively. Dilute with water toAniline or monomethylaniline—Place 5 mL in a glass-stop-90 mL. To provide a blank, place 90 mL of water in a thirdpered flask, add 5 mL of a solution of acetic anhydride inbeaker. To each beaker add 8.0 mL of trichloroacetic acidbenzene (1 in 10), mix, and allow to stand for 30 minutes.solution (3 in 20) and 1.0 mL of sodium nitrite solution (1Add 30.0 mL of 0.5 N sodium hydroxide VS, shake the mix-in 1000). Stir the solutions for 5 minutes, then add 10 mL ofture, add phenolphthalein TS, and titrate with 0.5 N hydro-acetate buffer TS, and 1.0 mL of a 1 in 1000 solution of N,chloric acid VS. Perform a blank determination, and makeN-dimethyl-1-naphthylamine in alcohol. The pH is about 5any necessary correction. Not more than 0.30 mL of 0.5 Nto 6, using pH paper. Stir for an additional 5 minutes, thensodium hydroxide is consumed by the test specimen.add 20 mL of glacial acetic acid. The pH is about 3 to 4,3,4-Dimethylbenzophenone, C15H14O—210.27using pH paper. In comparison with the blank, the beaker[2571-39-3]—White chunks melting at about 45°.containing 1.0 mL of the Sulfanilamide solution shows a pinkAssay—Inject an appropriate specimen into a suitable gas color, while the other beaker shows a deep pink to redchromatograph (see Chromatography ⟨621⟩) equipped with color.a flame-ionization detector, helium being used as the carrier N,N-Dimethyloctylamine, C10H23N—157.30gas. The following conditions have been found suitable: a [7378-99-6]—Colorless liquid.0.25-mm × 30-m capillary column coated with phase G1:

Refractive index ⟨831⟩: 1.4243 at 20°.the detector temperature and the injection port temperature2,5-Dimethylphenol, C8H10O—122.16 [95-87-4]—Useare maintained at 300°; the column temperature is main-

a suitable grade.tained at 180° and programmed to rise at the rate of 10°2,6-Dimethylphenol, (CH3)2C6H3OH—122.16per minute to 280° and held at that temperature for

[576-26-1]—White to pale yellow, crystalline solid.10 minutes. The area of the main peak is not less than 99%of the total peak area. Assay—Inject a 1 in 3 solution of it in xylene into a suita-

5,5-Dimethyl-1,3-cyclohexanedione, C8H12O2—140.18 ble gas chromatograph equipped with a flame-ionization[126-81-8]—White, crystalline solid. Slightly soluble in detector, helium being used as the carrier gas at a flow ratewater; soluble in alcohol, in methanol, in chloroform, and in of about 40 mL per minute. The following conditions haveacetic acid. been found suitable: a 3.2-mm × 1.83-m stainless steel col-

umn packed with 10% phase G25 on support S1A; the in-Melting range ⟨741⟩: between 148° and 150°.jection port temperature is maintained at about 250° andN,N-Dimethyldecylamine (1-(Dimethylamino)decane),the detector temperature at about 310°; the column tem-C4H9NO—185.35 [1120-24-7]—Use a suitable grade withperature is programmed to rise at 8° per minute from 100°a content of not less than 98%.to 200°. Similarly inject a specimen of xylene. The area of1,5-Dimethyl-1,5-diazaundecamethylenethe C8H10O peak is not less than 98% of the total peak areapolymethobromide (Polybrene), [28728-55-4]—This is acorrected for xylene.positively charged polymer. It is available as an off-white,

crystalline solid or powder and is extremely hygroscopic. Melting range ⟨741⟩: between 44° and 46°.Use a suitable reagent grade. 3,5-Dimethylphenol, C8H10O—122.16 [108-68-9]—

[NOTE—Commercially available as Polybrene.] Use a suitable grade.N,N-Dimethyldodecylamine-N-oxide (Lauryldimeth- [NOTE—A suitable grade is available as product number

ylamine-N-oxide), CH3(CH2)11NO(CH3)2—229.40 5600 from www.alfa.com.][1643-20-5]—Use a suitable grade. [NOTE—N,N- N,N-Dimethyl-p-phenylenediamine Dihydrochloride,Dimethyldodecylamine-N-oxide, 0.1 N in Water and N,N- (CH3)2NC6H4NH2 · 2HCl—209.12 [99-89-9]—NearlyDimethyldodecylamine-N-oxide, 30 Percent are suitable white, fine, crystalline, hygroscopic solid that may have agrades as well.] pinkish cast. Freely soluble in water; soluble in alcohol.

Dimethylethyl(3-hydroxyphenyl)ammonium Chloride— Assay—Transfer about 400 mg, accurately weighed, to aSee Edrophonium Chloride. 250-mL beaker, and dissolve in about 75 mL of water. Ti-

Dimethylformamide (N,N-Dimethylformamide), trate with 0.1 N sodium hydroxide VS, determining theHCON(CH3)2—73.09 [68-12-2]—Use ACS reagent grade. endpoint potentiometrically. Each mL of 0.1 N sodium hy-

N,N-Dimethylformamide Diethyl Acetal—147.22 droxide is equivalent to 10.46 mg of C8H12N2 · 2HCl. Not[1188-33-6]—Use a suitable grade. less than 98% is found.

[NOTE—A suitable grade is available from Sigma-Aldrich, Solubility—A solution of 1 g in 10 mL of water produceswww.sigma-aldrich.com.] not more than a slight haze.1,3-Dimethyl-2-imidazolidinone, C5H10N2O—114.15 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyl Tetrazolium[80-73-9]—Use a suitable grade. Bromide, C18H16N5SBr—414.3 [298-93-1]—Yellow to or-1,9-Dimethyl-methylene Blue, C36H46Cl4N6OS2Zn— ange powder. Use a suitable grade.850.1 [23481-50-7]—Dark green powder. Use a suitable Dimethyltin Dibromide, C2H6Br2Sn—308.59grade. [2767-47-7]—Use a suitable grade.[NOTE—A suitable grade is available from Sigma-Aldrich, m-Dinitrobenzene, C6H4(NO2)2—168.11 [99-65-0]—www.sigma-aldrich.com.] Pale yellow crystals or crystalline powder. Almost insolubleN,N-Dimethyl-1-naphthylamine, C12H13N—171.24 in cold water; slightly soluble in hot water. Soluble in chlo-[86-56-6]—Pale yellow to yellow, aromatic liquid. Soluble in roform and in benzene; sparingly soluble in alcohol. Is vola-alcohol and in ether. tile in steam.Assay—Transfer about 250 mg, accurately weighed, to a Melting range ⟨741⟩: between 89° and 92°.suitable beaker, add 100 mL of glacial acetic acid, and dis-

Residue on ignition (Reagent test): not more than 0.5%.solve by stirring. When solution is complete, titrate with 0.13,5-Dinitrobenzoyl Chloride, C7H3ClN2O5—230.56N perchloric acid VS, determining the endpoint potentio-

[99-33-2]—Pale yellow, crystalline powder. Freely soluble inmetrically. Perform a blank determination, and make anydilute sodium hydroxide solutions; soluble in alcohol.necessary correction. Each mL of 0.1 N perchloric acid is[CAUTION—Corrosive, moisture-sensitive, lachrymator, andequivalent to 17.12 mg of C12H13N. Not less than 98% ispossible mutagen. Store under nitrogen.]found.

Melting range ⟨741⟩: between 69° and 71°.Refractive index ⟨831⟩: between 1.6210° and 1.6230° atSolubility in sodium hydroxide—A solution of 500 mg in20°, sodium light being used.

25 mL of 1 N sodium hydroxide is clear or not more thanfaintly turbid.


Residue on ignition—Ignite 1 g with 0.5 mL of sulfuric Disodium Chromotropate (4,5-Dihydroxy-2,7-acid: the residue weighs not more than 1 mg (0.1%). naphthalenedisulfonic Acid, Disodium Salt), C10H6O8S2Na2 ·

2,4-Dinitrochlorobenzene, C6H3(NO2)2Cl—202.55 2H2O—400.29—Use ACS reagent grade Chromotropic Acid[97-00-7]—Yellow to brownish-yellow crystals. Insoluble in Disodium Salt.water; soluble in hot alcohol, in ether, and in benzene. Disodium Ethylenediaminetetraacetate—See Edetate Di-

sodium.Melting range ⟨741⟩: between 51° and 53°.Disodium Phosphate—See Sodium Phosphate.Residue on ignition—Ignite 500 mg with 5 drops of sulfu- 5,5′-Dithiobis(2-nitrobenzoic Acid) (3-Carboxy-4-ni-ric acid: the residue weighs not more than 1 mg (0.2%). trophenyl disulfide; Ellman’s reagent), C14H8N2O8S2—396.352,4-Dinitrofluorobenzene (1-Fluoro-2,4-dinitrobenzene), [69-78-3]—Yellow powder, melting at about 242°. SparinglyC6H3FN2O4—186.10 [70-34-8]—Light yellow solid. Use a soluble in alcohol.suitable grade. Dithiothreitol (Cleland’s Reagent; Threo-1,4-dimercapto-2,4-Dinitrophenylhydrazine, 2,4-C6H3(NO2)2NHNH2— 2,3-butanediol; DTT), HSCH2CH(OH)CH(OH)CH2SH—154.25198.14 [119-26-6]—Orange-red crystals, which under [3483-12-3]—Slightly hygroscopic needles from ether. Freelythe microscope appear individually to be lemon-yellow, lath- soluble in water, in alcohol, in acetone, in ethyl acetate, andlike needles. Very slightly soluble in water; slightly soluble in in ether.alcohol; moderately soluble in dilute inorganic acids. Use aMelting range ⟨741⟩: between 42° and 44°.suitable grade with a content of not less than 97%.

Dithizone (Diphenylthiocarbazone; PhenylazothioformicDioctyl Sodium Sulfosuccinate—Use Docusate Sodium.Acid 2-Phenylhydrazide), C6H5N:NCSNHNHC6H5—256.33Dioxane (Diethylene Dioxide; 1,4-Dioxane), C4H8O2—88.11[60-10-6]—Use ACS reagent grade.[123-91-1]—Use ACS reagent grade.

1-Dodecanol (Dodecyl Alcohol), CH3(CH2)11OH—186.33Diphenyl Ether (Phenyl Ether), (C6H5)2O—170.21[112-53-8]—A clear, colorless liquid. Crystallizes as leaflets[101-84-8]—A colorless liquid. Insoluble in water; soluble infrom dilute alcohol solution. Use ACS reagent grade.glacial acetic acid and in most organic solvents. Boils at

Dodecyl Alcohol—See 1-Dodecanol.about 259°.Dodecyl Lithium Sulfate (Lithium Dodecyl Sulfate, LithiumMelting range ⟨741⟩: between 26° and 28°. Lauryl Sulfate), C12H25LiO4S—272.3 [2044-56-6]—WhiteDiphenylamine, (C6H5)2NH—169.22 [122-39-4]—Use to off-white powder, clear to slightly hazy, colorless to faintACS reagent grade. yellow solution in water at 50 mg per mL at ambient tem-Diphenylborinic Acid, Ethanolamine Ester, (2-Ami- perature. The UV absorbance of a 0.1 M solution is less thannoethyl Diphenylborinate) C14H16BNO—225.09—White, crys- 0.05 at both 260 and 280 nm. The pH of a 0.1 M solutiontalline powder. Use a suitable grade. in water is 7.0 ± 0.5. Use a suitable grade.

Melting range ⟨741⟩: between 192° and 194°. Dodecyl Sodium Sulfonate (Sodium 1-Dodecanesulfonate;Diphenylcarbazide, (C6H5NHNH)2CO—242.28 1-Dodecanesulfonic Acid, Sodium Salt), C12H25SO3Na—272.38

[140-22-7]—Use ACS reagent grade 1,5-Diphenyl- [2386-53-0]—White, powdery solid. One g dissolves incarbohydrazide. 50 mL of warm water to yield a clear, colorless solution. Use

Diphenylcarbazone [Diphenylcarbazone compd. with a suitable grade.s-Diphenylcarbazide (1:1)], C6H5NHNHCON:NC6H5 · Melting point ⟨741⟩: higher than 300°.C6H5NHNHCONHNHC6H5—482.54 [538-62-5]—Use ACS 3-(Dodecyldimethylammonio)propanesulfonate (Laurylreagent grade Diphenylcarbazone Compound with sulfobetaine, N,N-dimethyl-N-dodecyl-N-(3-sulfopropyl)s-Diphenylcarbazide (1:1). ammonium betaine), C17H37NO3S—335.542,2-Diphenylglycine, C14H13NO2—227.26 [14933-08-5]—Use a suitable grade.[3060-50-2]—Off-white powder. Melts at about 244°, with Dodecyltriethylammonium Phosphate, 0.5 M,decomposition. [C12H25N · (C2H5)3]3PO4—906.52—Use a suitable grade.

Assay—Dissolve about 115 mg, accurately weighed, in [NOTE—A suitable grade is available as Ion Pair Cocktail30 mL of methanol. Slowly add about 20 mL of water, heat- Q12 (catalogue number 404031) from Regis Technologies,ing slightly if necessary for complete solution. Titrate with Inc., www.registech.com.]0.1 N sodium hydroxide VS, determining the endpoint po- Dodecyltrimethylammonium Bromidetentiometrically. Perform a blank determination and make (Lauryltrimethylammonium bromide), CH3(CH2)11N(CH3)3Br—any necessary correction. Each mL of 0.1 N sodium hydrox- 308.3 [1119-94-4]—Use a suitable grade.ide is equivalent to 22.73 mg of C14H13NO2. Not less than [NOTE—A suitable grade is available as catalog number98.0% is found. D5047 from Sigma-Aldrich, www.sigma-aldrich.com.]

Dipicrylamine—See Hexanitrodiphenylamine. Drabkin’s Reagent—The reagent consists of 100 parts ofDipropyl Phthalate, C14H18O4—250.29 [131-16-8]— sodium bicarbonate, 20 parts of potassium ferricyanide, and

Viscous, colorless liquid. 5 parts of potassium cyanide. [CAUTION—The reagent isAssay— HIGHLY TOXIC. Very toxic by inhalation, in contact with

skin, and if swallowed, and there is a risk of serious damageMOBILE PHASE—Prepare a mixture of acetonitrile and waterto eyes. Wear suitable protective clothing, gloves, and eye(52:48).and face protection. Do not mix with acids. Contact withPROCEDURE—Inject about 20 µL into a suitable liquid chro-acids liberates a very toxic gas. If ingested, perform gastricmatograph (see Chromatography ⟨621⟩) equipped with alavage, and call a physician.]230-nm detector and a 4.6-mm × 15-cm column that con-

[NOTE—The reagent can be obtained from many manu-tains packing L1. The flow rate is about 2.0 mL per minute.facturers and suppliers. Some examples of manufacturers orThe area of the C14H18O4 peak is not less than 99% of thesuppliers are the following: Sigma Chemical Co., St. Louis,total peak area.MO; and CIMA Scientific, Dallas, TX.]Refractive index ⟨831⟩: between 1.495 and 1.499 at 20°. Dried Peptone—See Peptone, Dried.4,4′-Dipyridyl, C10H8 N2—156.18 [553-26-4]—Use a Earth, Chromatographic, Silanized, Acid-Basesuitable grade. [NOTE—A suitable grade is available from Washed—Use a suitable grade.Sigma-Aldrich Catalog number 289426.] [NOTE—A suitable chromatographic grade is “Gas-Chromα,α′-Dipyridyl—See 2,2′-Bipyridine. Q,” available from Alltech, www.alltechweb.com.]

Edetate Disodium (Disodium Ethylenediaminetetraacetate)C10H14N2O8Na2 · 2H2O—372.24—Use ACS reagent grade(Ethylenedinitrilo)tetraacetic Acid Disodium Salt Dihydrate.


n-Eicosane, C20H42—282.55 [112-95-8]—White, crys- [NOTE—Suitable peroxide test strips can be obtained fromtalline solid. EMD Chemicals, www.emdchemicals.com, or from J. T.

Baker, www.mallbaker.com.]Melting range ⟨741⟩: between 37° and 39°.Ethidium Bromide, C21H20N3Br—394.3 [1239-45-8]—Eicosanol [629-96-9]—Use a suitable grade.

Purple to purple-red powder. Use a suitable grade.Eosin Y (Eosin Yellowish Y) (Certified Biological Eosin Y;4′-Ethoxyacetophenone, C10H12O2—164.20Sodium Tetrabromofluorescein), C20H6Br4Na2O5—691.85

[1676-63-7]—White to tan crystals.[17372-87-1]—Red to brownish-red pieces or powder. UseACS reagent grade. Assay—Dissolve about 50 mg in 1 mL of ether. Inject

Epiandrosterone (trans-Androsterone, 5α-Androstan-3β-ol- about 1 µL of this solution into a suitable gas chromato-17-one), C19H30O2—290.44 [481-29-8]—Use a suitable graph (see Chromatography ⟨621⟩) equipped with a flame-grade. ionization detector and a 0.25-mm × 30-m capillary column

[NOTE—A suitable grade is available as catalog number containing stationary phase G1. The carrier gas is helium.E3375 from www.sigma-aldrich.com.] The chromatograph is programmed as follows. Initially, the

Equilenin, C18H18O2—266.33 [517-09-9]—Colorless or column temperature is equilibrated at 180°, then the tem-white crystals or crystalline powder. Insoluble in water; solu- perature is increased at a rate of 10° per minute to 280°,ble in chloroform and in dioxane; moderately soluble in al- and maintained at 280° for 10 minutes. The injection portcohol. temperature is maintained at 280°, and the detector is

maintained at 300°. The area of the 4′-ethoxyacetophenoneMelting range, Class II ⟨741⟩: between 256° and 260°.peak is not less than 97.5% of the total peak area.Specific rotation ⟨781⟩: between +85° and +88°, deter-

Melting range ⟨741⟩: between 34° and 39°.mined in a solution in dioxane containing 75 mg of equi-2-Ethoxyethanol (Ethylene Glycol Monoethyl Ether),lenin in each 10 mL.

C4H10O2—90.12 [110-80-5]—Clear, colorless liquid. Mis-Absorption maxima—An alcohol solution exhibits absorp- cible with water, with alcohol, with ether, and with acetone.tion maxima at 231, 282, 325, and 340 nm.Specific gravity ⟨841⟩: about 0.93.α-Ergocryptine, C32H41N5O5—575.70 [511-09-1]—Use

a suitable grade. Boiling range (Reagent test)—Not less than 95% distillsEriochrome Black T–Sodium Chloride Indicator—Mix between 133° and 135°.

0.1 g of eriochrome black T and 10 g of sodium chloride, Ethyl Acetate, CH3COOC2H5—88.11 [141-78-6]—Useand triturate until the mixture becomes homogenous. ACS reagent grade.

Eriochrome Cyanine R, C23H15Na3O9S—536.40 Ethyl Acrylate [140-88-5]—Use a suitable grade.[3564-18-9]—Dark, red-brown powder. Freely soluble in Ethyl Alcohol (Alcohol; Ethanol), C2H5OH—46.07—Use Al-water; insoluble in alcohol. cohol.

Ethyl Arachidate, C22H44O2—340.6 [18281-05-5]—UseSolubility—200 mg in 100 mL of water yields a solutiona suitable grade.that remains clear and free from undissolved matter for

Ethyl Benzoate, C9H10O2—150.17 [93-89-0]—Clear,30 minutes.colorless liquid. Practically insoluble in water; miscible withLoss on drying ⟨731⟩—Dry it in vacuum over silica gel to alcohol, with chloroform, and with ether.constant weight: it loses not more than 2% of its weight.

Assay—Inject an appropriate specimen into a suitable gasResidue on ignition (Reagent test)—0.5 g, treated with chromatograph (see Chromatography ⟨621⟩), helium being1 mL of sulfuric acid and 2 mL of nitric acid, yields between used as the carrier gas. The following conditions have been42.0% and 44.0% of the dry weight (theoretical yield is found suitable: a 3-mm × 2.4-m stainless steel column con-42.9% of Na2SO4). taining 20% phase G16 on support S1A; the injection port,Sensitiveness—Add 2 mL of a solution (1 in 1000) to 1 mL column, and detector temperatures are maintained at 180°,

of aluminum sulfate solution (1 in 10,000), heat at 37 ± 3° 195°, and 250°, respectively. The area of the ethyl benzoatefor 5 minutes, cool, and add 1 mL of sodium acetate TS: a peak is not less than 98% of the total peak area.strong red to red-violet color is produced in not more than Refractive index ⟨831⟩: between 1.5048 and 1.5058 at5 minutes. 20°.Escin [6805-41-0]—Use a suitable grade. Ethyl Cyanoacetate, CNCH2COOC2H5—113.11Ethanesulfonic Acid, C2H5SO3H—110.13 [594-45-6]— [105-56-6]—Colorless to pale yellow liquid. Slightly solubleColorless to light yellow liquid. Soluble in water. in water. Miscible with alcohol and with ether. At atmos-

Assay—Accurately weigh about 300 mg, dissolve in pheric pressure it boils between 205° and 209°, with de-30 mL of water, add phenolphthalein TS, and titrate with composition. At a pressure of 10 mm of mercury it distills at0.1 N sodium hydroxide VS. Each mL of 0.1 N sodium hy- about 90°.droxide is equivalent to 11.013 mg of C2H5SO3H: between Specific gravity ⟨841⟩: between 1.057 and 1.062.94.0% and 106.0% is found.

Acidity—Dissolve 2 mL in 25 mL of neutralized alcohol,Refractive index ⟨831⟩: between 1.432 and 1.436 at add phenolphthalein TS, and titrate with 0.10 N sodium20°. hydroxide: not more than 1.5 mL is required to produce aEther—See Ethyl Ether. pink color.Ether, Absolute—See Ethyl Ether, Anhydrous. Ethyl Ether (Diethyl Ether; Ether), (C2H5)2O—74.12Ether, Diphenyl—See Diphenyl Ether. [60-29-7]—Use ACS reagent grade.Ether, Isopropyl—See Diisopropyl Ether. Ethyl Ether, Anhydrous (Diethyl Ether, Anhydrous; Ether,Ether, Nonyl Phenyl Polyethylene Glycol—See (p-tert- Absolute), (C2H5)2O—74.12 [60-29-7]—Use ACS reagentOctylphenoxy)nonaethoxyethanol. grade.Ether, Peroxide-Free (Diethyl Ether; Ether), (C2H5)2O— Ethyl Salicylate, C9H10O3—166.17 [118-61-6]—Color-74.12—Use ACS reagent grade. less liquid.Peroxide—Transfer 8 mL of potassium iodide and starch Assay—Inject an appropriate specimen into a suitable gasTS to a 12-mL ground glass-stoppered cylinder about chromatograph (see Chromatography ⟨621⟩) equipped with15 mm in diameter. Fill completely with the substance a flame-ionization detector, helium being used as the carrierunder test, mix, and allow to stand protected from light for gas. The following conditions have been found suitable: a5 minutes. No color develops. Alternatively, peroxide test 0.25-mm × 10-m capillary column coated with a 1-µm layerstrips may be used. of methylsilicone; the injection port temperature is main-

tained at 240°; the detector temperature is maintained at300°; the column temperature is maintained at 150° andprogrammed to rise 10° per minute to 250°. The area of


the ethyl salicylate peak is not less than 99% of the total potentiometrically, using a silver-ion selective electrode andpeak area. a calomel reference electrode containing 1 M potassium ni-

trate. Perform a blank determination, and make any neces-Refractive index ⟨831⟩: between 1.5216 and 1.5236 atsary correction. Each mL of 0.1 N silver nitrate is equivalent20°.to 29.92 mg of C12H14IN: not less than 97.0% is found.2-Ethylaminopropiophenone Hydrochloride,

Factor Xa (Activated Factor X) for Anti-Factor Xa Test—C6H5COCH(CH3)NHC2H5 · HCl—213.70 [51553-17-4]—Factor Xa is the proteolytic enzyme derived from bovineUse a suitable grade.plasma, and it cleaves prothrombin to form thrombin. It is a4-Ethylbenzaldehyde, C2H5C6H4CHO—134.18glycoprotein having a molecular weight of 40,000. One Fac-[4748-78-1]—Colorless to pale yellow liquid.tor Xa Unit is the amount of activated endogenous Factor XAssay—Dissolve about 600 mg, accurately weighed, in a (55,000 Da when nonactivated) that is contained in 1 mL ofmixture of 100 mL of alcohol and 25 mL of 1 M hydroxyla- normal plasma. Russell’s viper venom is used to activate themine hydrochloride in a beaker. Cover the beaker with a enzyme, and is then removed. The preparation is stabilizedwatch glass. Heat gently until condensate begins to form on and lyophilized.the watch glass. Allow to cool for about 30 minutes. Titrate Factor Xa is free of thrombin at the concentration used inwith 0.5 N sodium hydroxide VS, determining the endpoint the test. When tested against pure fibrinogen, no clottingpotentiometrically. Perform a blank determination, and takes place within 24 hours. It has not less than 40 Factor Xamake any necessary correction. Each mL of 0.5 N sodium Units per mg of protein, and exhibits 90% homogeneityhydroxide is equivalent to 67.09 mg of C2H5C6H4CHO. Not when tested by disk electrophoresis.less than 98% is found. One Factor Xa Unit per mL gives a 15-second clottingEthylbenzene, C8H10—106.17 [100-41-4]—Not less time when tested in the following manner. Mix 0.1 mL of athan 99.5%. saturated solution of cephalin (derived from rabbit brain-Ethylene Dichloride (1,2-Dichloroethane), C2H4Cl2—98.96 acetone powder or from an equivalent amount of rabbit[107-06-2]—Use ACS reagent grade 1,2-Dichloroethane. brain thromboplastin) in 0.1 mL of citrated bovine plasmaEthylene Glycol, HOCH2CH2OH—62.07 [107-21-1]— and 0.1 mL of 0.025 M calcium chloride. Immediately addClear, colorless, slightly viscous, hygroscopic liquid. Slightly 0.1 mL of a solution of factor Xa (1 in 10), and incubate atsoluble in ether; practically insoluble in benzene. Miscible 37°.with water and with alcohol. Fast Blue B Salt, C14H12N4O2 · ZnCl4—475.47

Specific gravity ⟨841⟩: about 1.11. [91-91-8]—Green powder.Boiling range (Reagent test): between 194° and 200°. Loss on drying ⟨731⟩—Dry it in vacuum at 110° forResidue on ignition—Evaporate 100 mL (110 g) in a tared 1 hour: it loses not more than 5.0% of its weight.

evaporating dish over a flame until the vapors continue to Absorbance—Dissolve 50 mg in 100 mL of water. In aburn after the flame is removed. Allow the vapors to burn second container dissolve 100 mg of 2-naphthol in 100 mLuntil the specimen is consumed. Ignite at 800 ± 25° for of 2-methoxyethanol. Pipet 5 mL of the test solution and1 hour, cool, and weigh: the residue weighs not more than 10 mL of the 2-naphthol solution into a 100-mL volumetric5.5 mg (0.005%). flask, and dilute with acetone to volume. For the blank, pi-

Acidity—Add 0.2 mL of phenol red TS to 50 mL of water, pet 5 mL of water and 10 mL of 2-naphthol solution into aand titrate with 0.1 N sodium hydroxide to a red endpoint. second 100-mL volumetric flask, and dilute with acetone toAdd 50 mL (55 g) of ethylene glycol, and titrate with 0.1 N volume. Determine the absorbance of the test solution in asodium hydroxide: not more than 1 mL is required to re- 1-cm cell at the wavelength of maximum absorbance atstore the red color (0.01% as CH3COOH). about 545 nm, with a suitable spectrophotometer, using the

blank to set the instrument: the absorbance is not less thanChloride (Reagent test)—A 4.5-mL (5-g) portion shows0.80.not more than 0.025 mg of Cl (5 ppm).

Fast Blue BB Salt, (C17H18ClN3O3)2 · ZnCl2—831.89Water, Method I ⟨921⟩: not more than 0.20%.[15710-69-7]—Yellow powder melting at about 162°, withEthylene Glycol Monoethyl Ether—See 2-Ethoxyethanol.decomposition. Sparingly soluble in water.Ethylene Oxide in Methylene Chloride (50 mg/mL)—

Chloride—Transfer about 80 mg, accurately weighed, to aUse a suitable grade.suitable beaker. Add 25 mL of acetone, 25 mL of water, and[NOTE—A suitable grade is available from Sigma Aldrich500 mg of sodium nitrate. Stir until solution is complete.Corporation, www.sigma-aldrich.com.]Titrate with 0.01 N silver nitrate VS, determining the endEthylenediamine (1,2-Diaminoethane) C2H8N2—60.10point potentiometrically. Perform a blank determination and[107-15-3]—Use a suitable grade with a content of not lessmake any necessary correction. Not less than 15.0% of chlo-than 99%.ride is found.N-Ethylmaleimide (1-Ethyl-1H-pyrrole 2,5-Dione),

Fast Green FCF, C37H34N2Na2O10S3—808.86C6H7NO2—125.12 [128-53-0]—Use a suitable grade.[2353-45-9]—Red to brown-violet powder or crystals. Solu-Melting range ⟨741⟩: between 43° and 47°.ble in water; sparingly soluble in alcohol. Use a suitable2-Ethyl-2-methylsuccinic Acid, C7H12O4—160.17—Whitegrade.crystals.

FD&C Blue No. 1 (Brilliant Blue), C37H34N2O9S3Na2—Assay—Transfer about 80 mg, accurately weighed, to a 792.86 [3844-45-9]—Use a suitable grade.suitable beaker, add 30 mL of methanol, and dissolve by Ferric Ammonium Citrate—Thin, transparent, garnet-redstirring. Slowly add 40 mL of deionized water. [NOTE—If scales or granules or brownish-yellow powder. Is deliques-cloudiness appears when adding the deionized water, dis- cent and is affected by light. Very soluble in water; insolublesolve in 50 mL of methanol only.] When solution is com- in alcohol.plete, titrate with 0.1 N sodium hydroxide VS, determiningAssay—Accurately weigh about 1 g, dissolve in 25 mL ofthe endpoint potentiometrically. Perform a blank titration,

water in a glass-stoppered flask, add 5 mL of hydrochloricand make any necessary correction. Each mL of 0.1 N so-acid and 4 g of potassium iodide, insert the stopper in thedium hydroxide is equivalent to 16.02 mg of C7H12O4. Notflask, and allow to stand in the dark for 15 minutes. Addless than 98.5% of C7H12O4 is found.100 mL of water, and titrate the liberated iodine with 0.1 NMelting point ⟨741⟩: between 101° and 103°. sodium thiosulfate VS, adding 3 mL of starch TS as the1-Ethylquinaldinium Iodide, C12H14IN—299.15 endpoint is approached. Perform a blank determination, and[606-55-3]—Yellow-green solid. Sparingly soluble in water. make any necessary correction. Each mL of 0.1 N sodium

Assay—Dissolve about 290 mg, accurately weighed, in thiosulfate is equivalent to 5.585 mg of Fe: between 16.5%100 mL of water, and add 10 mL of glacial acetic acid. Ti- and 18.5% is found.trate with 0.1 N silver nitrate VS, determining the endpoint


Ferric citrate—To 250 mg dissolved in 25 mL of water add Zinc—To the combined acid extracts saved from the Cop-1 mL of potassium ferrocyanide TS: no blue precipitate is pertest, add 0.5 M sodium acetate to bring the pH betweenformed. 5.0 and 5.5, and then add 1 mL of 0.1 N sodium thiosul-

fate. Add 10 mL of Standard Dithizone Solution (see LeadTartrate—Dissolve 1 g in 10 mL of water, add 1 mL of⟨251⟩), shake for 2 minutes, and allow the layers to separate.potassium hydroxide TS, boil to coagulate the ferric hydrox-Draw off the dithizone, and discard the water layer. Anyide, adding more potassium hydroxide TS, if necessary, topink color is not greater than that in a control prepared byprecipitate all of the iron, filter, and slightly acidify the fil-adding 0.006 mg of zinc ion (Zn) to the combined acidtrate with glacial acetic acid. Add 2 mL of glacial acetic acid,extracts from the control used in the test for Copperand allow to stand for 24 hours: no crystalline white precipi-(0.005%).tate is formed.

Nitrate—Dissolve 10 g in 100 mL of dilute sulfuric acid (1Lead ⟨251⟩—Dissolve 1.0 g in 30 mL of water, add 5 mLin 100), heat to boiling, and pour, slowly, into a mixture ofof dilute nitric acid (1 in 21), boil gently for 5 minutes, cool,140 mL of water and 50 mL of stronger ammonia TS. Filterand dilute with water to 50 mL: 20 mL of the solutionthrough a folded filter while still hot, wash with hot watershows not more than 0.008 mg of Pb (0.002%).until the volume of the filtrate is 300 mL, mix, and cool. ToFerric Ammonium Sulfate, FeNH4(SO4)2 · 12H2O—15 mL of this solution add 1 mL of sodium chloride solution482.19—Use ACS reagent grade.(1 in 200), 0.10 mL of indigo carmine TS, and 15 mL ofFerric Chloride, FeCl3 · 6H2O—270.29 [10025-77-1]—sulfuric acid. The blue color is not completely discharged atUse ACS reagent grade.the end of 5 minutes (0.01%).Ferric Nitrate, Fe(NO3)3 · 9H2O—404.00

[10421-48-4]—Use ACS reagent grade. Substances not precipitated by ammonia—Evaporate toFerric Sulfate, Fe2(SO4)3 · xH2O [10028-22-5]—Grayish- dryness 30 mL of the filtrate obtained in the test for Nitrate,

white, hygroscopic powder, or fawn-colored pearls, slowly and ignite gently: the weight of residue does not exceedsoluble in water. 1 mg (0.10%).

Ferrocyphen (Dicyano-bis (1,10-phenantroline) iron (II)Assay—Accurately weigh about 700 mg, and dissolve it inComplex), (C12H8N2)2Fe(CN)2—468.3—Brown to black pow-a mixture of 50 mL of water and 3 mL of hydrochloric acidder. Dark red solution at 10 mg per mL in glacial aceticin a glass-stoppered flask. Add 3 g of potassium iodide, andacid. Soluble in chloroform and in water at 5 mg per mL,allow to stand in the dark for 30 minutes. Then dilute withyielding a clear purple solution in chloroform and a clear100 mL of water, and titrate with 0.1 N sodium thiosulfateorange solution in water.VS, adding 3 mL of starch TS as the endpoint is approached.

Each mL of 0.1 N sodium thiosulfate is equiv- Water, Method I ⟨921⟩: not more than 10%.alent to 5.585 mg of Fe: not less than 21.0% and not more Ferrous Ammonium Sulfate, Fe(NH4)2(SO4)2 · 6H2O—than 23.0% is found. 392.14—Use ACS reagent grade.

Ferrous Sulfate, FeSO4 · 7H2O—278.02 [7782-63-0]—Insoluble matter (Reagent test)—A 10-g portion, dissolvedUse ACS reagent grade.in a mixture of 100 mL of water and 5 mL of sulfuric acid,

Ferulic Acid (4-Hydroxy-3-methoxycinnamic acid),shows not more than 2 mg of insoluble matter (0.02%).C10H10O4—194.19 [1135-24-6]—Use a suitable grade.Chloride—Dissolve 1 g by warming with a mixture of Fibroblast Growth Factor-2—Use a suitable grade.10 mL of water and 1 mL of nitric acid, add 4 mL of addi- [NOTE—A suitable grade can be obtained from Roche Di-tional nitric acid, and dilute with water to 50 mL. To 25 mL agnostics Corporation, www.roche-diagnostics.com.]add 1 mL of phosphoric acid and 1 mL of silver nitrate TS. Filter Paper, Quantitative—For the Mercuric Bromide TestAny turbidity does not exceed that produced in a control Paper used in testing for arsenic, use Swedish O filter papercontaining 0.01 mg of chloride ion (Cl), 1 mL of nitric acid, or other makes of like surface, quality, and ash.1 mL of phosphoric acid, and 1 mL of silver nitrate TS Fluorene, C13H10—166.22 [86-73-7]—White to off-(0.002%). white crystals or powder. Soluble in benzene, in carbon di-

Ferrous iron—Dissolve 4 g by warming with 50 mL of disulfide, in ether, and in hot alcohol; freely soluble in glaciallute sulfuric acid (1 in 10), cool, and titrate with 0.1 N acetic acid.potassium permanganate: not more than 0.16 mL is re- Solubility test—One g dissolves in 10 mL of acetone toquired to produce a permanent pink color (0.02% as Fe+2). yield a clear and complete solution.[NOTE—Because the reagents used in the tests for Copper

Melting range ⟨741⟩: between 113° and 117°, within a 2°and Zinc may contain excessive amounts of copper andrange.zinc, they should first be purified by extracting with

9-Fluorenylmethyl Chloroformate, C15H11ClO2—258.70Dithizone Extraction Solution(see Lead ⟨251⟩).][28920-43-6]—Clear, colorless solid. Melts at about 62°.Copper—Dissolve 1.2 g in 100 mL of water. To 10 mL add Fluorescamine, C17H10O4—278.26 [38183-12-9]—50 mL of a solution containing 5 g of ammonium tartrate White to off-white powder. Very slightly soluble in water;and 5 mL of ammonium hydroxide. Add 10 mL of Standard freely soluble in methylene chloride; soluble in alcohol;Dithizone Solution (see Lead ⟨251⟩), shake for 2 minutes, slightly soluble in chloroform.draw off the dithizone layer, and compare the pink color

Assay—Dissolve about 600 mg in 75 mL of dimethylform-with that in a control containing 6 µg of copper ion (Cu)amide, and titrate with 0.1 N lithium methoxide to a blueand treated exactly as the 10-mL portion of test solution. Ifendpoint, using 1% thymol blue in dimethylformamide asthe color in the test solution is less than that in the control,the indicator. Perform a blank determination, and make anythen the test specimen contains less than the limit of bothnecessary correction. Each mL of 0.1 N lithium methoxide isCopper and Zinc. If the color in the test solution is moreequivalent to 27.83 mg of C17H10O4. Not less than 99% isthan that in the control, add 15 mL of dilute hydrochloricfound.acid (1 in 250), and shake for 2 minutes. Draw off the

dithizone solution, and shake with a second 15 mL of dilute Loss on drying ⟨731⟩—Dry it at 105° for 4 hours: it loseshydrochloric acid (1 in 250) for 2 minutes. Draw off the not more than 0.5% of its weight.dithizone, combine the two acid extracts, and reserve for 4′-Fluoroacetophenone, FC6H4COCH3—138.14the Zinc test. Any pink color in the dithizone solution is not [403-42-9]—Colorless liquid.darker than that in the control solution treated exactly asthe test solution (0.005%).


Assay—Inject an appropriate specimen into a suitable gas Specific rotation ⟨781⟩: between +3.8° and +4.8°, deter-chromatograph (see Chromatography ⟨621⟩) equipped with mined in a solution of pyridine containing 10 mg per mL,a flame-ionization detector, helium being used as the carrier with the use of a mercury light at 546.1 nm; between +21°gas. The following conditions have been found suitable: a and +25°, determined in a solution of equal parts of chloro-25-mm × 30-m capillary column coated with a 1-µm layer form and methanol containing 5 mg per mL, with the useof phase G2; the injection port temperature is maintained at of sodium light.200°; the detector temperature is maintained at 250°; the Suitability—Dissolve 10 mg each of USP Digitoxin RS, pre-column temperature is maintained at 100° and pro- viously dried, USP Digoxin RS, previously dried, and gitoxin,grammed to rise 10° per minute to 250°. The area of the respectively, in separate 5-mL portions of a mixture ofFC6H4COCH3 peak is not less than 99% of the total peak 2 parts of chloroform and 1 part of methanol, and dilutearea. each with additional solvent mixture to 10 mL. Then pro-

Refractive index ⟨831⟩: 1.510 at 20°. ceed as directed in the Identification test under Digoxin. TheFormaldehyde Solution, HCHO—(30.03) and water— chromatogram of gitoxin shows one fluorescent spot, lo-

Use ACS reagent grade. cated between the digoxin and digitoxin spots.Formamide, HCONH2—45.04 [75-12-7]—Use ACS re- Glacial Acetic Acid—See Acetic Acid, Glacial.

agent grade. Glass Wool—Fine threads of glass.Preparation for Digitoxin Assay—To ensure freedom from Acid-soluble substances—Boil 1 g for 30 minutes with

ammonia, treat Formamide as follows. Shake a suitable 30 mL of diluted hydrochloric acid, and filter. Evaporate thequantity of formamide with about 10% of its weight of an- filtrate, and dry the residue at 105° to constant weight: thehydrous potassium carbonate for 15 minutes, and filter. Dis- residue weighs not more than 5 mg (0.5%).till the filtrate in an all-glass apparatus under vacuum at a Heavy metals—Boil 2 g with a mixture of 25 mL each ofpressure of about 25 mm of mercury or less. Reject the first diluted nitric acid and water for 5 minutes, and filter. Evapo-portion of distillate containing water, and collect the frac- rate one-half of the filtrate to dryness, dissolve the residue intion that boils at about 115° at a pressure of 25 mm of 10 mL of water to which 3 drops of hydrochloric acid havemercury or at 101° at a pressure of 12 mm of mercury. been added, filter if necessary, and add an equal volume ofStore in tight containers, protected from light. hydrogen sulfide TS to the filtrate: no darkening is pro-

Formamide, Anhydrous, HCONH2—45.04 duced.[75-12-7]—Use formamide that has a water content of less D-Gluconic Acid, 50 Percent in Water, C6H12O7—196.16than 0.1%. [526-95-4]—Pale yellow liquid.

Formic Acid, HCOOH—46.03 [64-18-6]—Use ACS rea- Assay—Dilute about 200 mg of the solution, accuratelygent grade Formic Acid, 88 Percent. weighed, with 30 mL of water. Titrate with 0.1 N sodiumFormic Acid, 96 Percent, HCOOH—46.03 [64-18-6]— hydroxide VS, determining the endpoint potentiometrically.Use ACS reagent grade Formic Acid, 96 Percent. Perform a blank determination and make any necessary cor-Formic Acid, Anhydrous—Use ACS reagent grade Formic rection. Each mL of 0.1 N sodium hydroxide is equivalent toAcid, 96 Percent. 19.62 mg of C6H12O7. Not less than 49.0% is found.Fuchsin, Basic (Basic Red 9, Parafuchsin Hydrochloride),Refractive index ⟨831⟩: between 1.4160 and 1.4180 atC19H17N3—323.82 [569-61-9]—Use a suitable grade.

20°.Fuller’s Earth, Chromatographic—(Very Fine and Moder-Specific rotation ⟨781⟩: between +9.9° and +11.9°, deter-ately Coarse)—Gray or grayish-white powder or granules

mined as is, at 20°.consisting mainly of hydrous aluminum-magnesium silicate.Glucose, C6H12O6—180.2 [50-99-7]—Use a suitablePowder fineness—See Powder Fineness ⟨811⟩.

grade. A white, crystalline powder. Freely soluble in water;Soluble matter—Twenty g, treated with 50 mL of cold sparingly soluble in alcohol.water and filtered, yields not more than 60 mg of residue D-Glucuronolactone, C6H8O6—176.12 [32449-92-6]—upon evaporation of the filtrate (0.3%). A second 20-g por- Use a suitable grade.tion, treated with 50 mL of cold alcohol and filtered, yields Glutamic Acid, C5H9NO4—147.13 [56-86-0]—Use anot more than 14 mg upon evaporation of the filtrate suitable grade.(0.07%). L-Glutamic Acid, C5H9NO4—147.1 [56-86-0]—WhiteLoss on drying ⟨731⟩—Dry it at 105° for 6 hours: it loses powder or white powder with a faint yellow cast. Use a

between 7.0% and 10.0% of its weight. suitable grade.[NOTE—Adjust the water content, if necessary, by drying L-Glutamine, C5H10N2O3—146.15 [56-85-9]—White,

in vacuum at room temperature, restoring the water re- crystalline powder. Use a suitable grade.quired, and equilibrating by shaking for 2 hours.] Glycerin (Glycerol) [56-81-5]—Use ACS reagent grade

Fuming Nitric Acid—See Nitric Acid, Fuming. Glycerol.Fuming Sulfuric Acid—See Sulfuric Acid, Fuming. Glycolic Acid, C2H4O3—76.05 [79-14-1]—White crys-Furfural (2-Furancarboxyaldehyde; 2-Furaldehyde), talline powder or chunks.

C4H3OCHO—96.08 [98-01-1]—Use ACS reagent grade. Assay—G Designations—See phases for gas chromatographySILYLATING REAGENT: Pyridine, hexamethyldisilazane, chloro-under Reagents, Chromatographic Columns.

trimethylsilane (9:3:1)Gadolinium (Gd III) Acetate Hydrate, (CH3CO2)3Gd ·SAMPLE PREPARATION: Weigh approximately 25 mg (aboutxH2O—334.38 [100587-93-7]—White, crystalline, hygro-

3 drops) of the sample into a test tube. Add 2 mL of thescopic powder. Irritant. Use a suitable grade.Silylating reagent and cap the test tube. Mix well and allowGeneticin (G418; O-2-Amino-2,7-dideoxy-D-glycero-alpha-to incubate at room temperature for a minimum of 2 h. AD-glucoheptopyranosyl-(1-4)-O-(3-deoxy-4-C-methyl-3-(methyl-white precipitate of ammonium chloride will form. Centri-amino)-beta-L-arabinopyranosyl-(1-6)-D-streptamine),fuge and use the clear supernatant for injection.C20H40N4O10—496.55 [49863-47-0]—Use a suitable grade,

cell culture tested. PROCEDURE: Inject an appropriate volume of the SampleGirard Reagent T—See Trimethylacethydrazide Ammonium preparation into a gas chromatograph (see Chromatography

Chloride. ⟨621⟩) equipped with a flame-ionization detector, heliumGitoxin, C41H64O14—780.94 [4562-36-1]—White, crys- being used as the carrier gas. The following conditions have

talline powder. Practically insoluble in water, in chloroform, been found suitable: a 0.25-mm × 30-m capillary columnand in ether; slightly soluble in pyridine and in diluted alco- coated with a 1-µm layer of phase G2. The injection porthol. Melts at about 250°, with decomposition. temperature is maintained at 250°; the detector tempera-

ture is maintained at 300°; the column temperature is main-


tained at 100° and programmed to rise 10° per min to [NOTE—A suitable grade is available as Bovine Hemoglobin250°. The area of the peak corresponding to C2H4O3 is NLT substrate powder from Sigma-Aldrich, www.sigma-aldrich.98.5% of the total peak area. com.]

Gold Chloride (Chlorauric Acid), HAuCl4 · 3H2O—393.83 1-Heptadecanol, C17H36O—256.48 [1454-85-9]—Use[16903-35-8]—Use ACS reagent grade. a suitable grade.

Guaiacol (o-Methoxyphenol), C7H8O2—124.14 Heptafluorobutyric Acid, C4F7O2H—214.04[95-05-1]—Colorless to yellowish, refractive liquid. Soluble [375-22-4]—Use a suitable grade.in about 65 parts of water; soluble in sodium hydroxide so- Heptakis-(2,6-di-O-methyl)-β-cyclodextrin (2,6-Di-O-lution; miscible with alcohol, with chloroform, with ether, methyl-β-cyclodextrin; Dimethyl-β-cyclodextrin) C56H98O35—and with glacial acetic acid. 1331.36 [51166-71-3]—Use a suitable grade.

n-Heptane—Use n-Heptane, Chromatographic.Assay—When examined by gas–liquid chromatography, itn-Heptane, Chromatographic C7H16—100.21shows a purity of not less than 98%. The following condi-

[142-82-5]—Clear, colorless, volatile, flammable liquid con-tions have been found suitable for assaying it: a 3-mm ×sisting essentially of C7H16. Practically insoluble in water; sol-1.8-m stainless steel column containing liquid phase G16 onuble in absolute alcohol. Miscible with ether, with chloro-60- to 80-mesh support S1A. Helium is the carrier gas, theform, with benzene, and with most fixed and volatile oils.injection port temperature is maintained at 180°, the col-Use a suitable grade, chromatographic or HPLC, with a con-umn temperature is maintained at 200°, and the flame-ioni-tent of not less than 99%.zation detector is maintained at 280°. The retention time is

Heptyl p-Hydroxybenzoate (Heptyl 4-Hydroxybenzoate;about 8 minutes.N-Heptyl 4-Hydroxybenzoate; Benzoic Acid, 4-Hydroxy-, HeptylRefractive index ⟨831⟩: between 1.5430 and 1.5450, at Ester), C14H20O3—236.31 [1085-12-7]—Use a suitable20°. grade with a content of NLT 98%.Guanidine Hydrochloride, (Aminoformamidine Hydrochlo- Hexadecyl Hexadecanoate (Hexadecyl Palmitate; Cetylride; Aminomethanamidine Hydrochloride), CH5N3 · HCl— Palmitate), C32H64O2—480.85 [540-10-3]—Use a suitable95.53 [50-01-1]—White, crystalline powder. Freely solu- grade.ble in water and in alcohol. Use a suitable grade with a [NOTE—Suitable grades are available commercially ascontent not less than 99%. Hexadecyl Palmitate and Palmitic Acid Palmityl Ester fromGuanidine Isothiocyanate, C2H6N4S—118.2 Sigma-Aldrich, www.sigma-aldrich.com, and Cetyl Palmitate,[593-84-0]—White powder or colorless crystals. Use a suita- Catalog number C1203, from Spectrum Chemical Mfg.ble grade. Corp., www.spectrumchemical.com.]Guanine Hydrochloride, C5H5N5O · HCl · H2O—205.60 Hexadecyltrimethylammonium Bromide—See Cetyl-[635-39-2]—White, crystalline powder. Melts above 250°, trimethylammonium Bromide.with decomposition. Slightly soluble in water and in alcohol; Hexadimethrine Bromide, (C13H30Br2N2)n [28728-55-4]—soluble in acidulated water and in sodium hydroxide TS. Its White to off-white powder, hygroscopic, amorphous poly-solutions are not precipitated by iodine TS or by mer. Soluble in water up to 10% to give a colorless to lightmercuric–potassium iodide TS, but form a precipitate with yellow solution. Use a suitable grade.trinitrophenol TS. Hexamethyldisilazane, C6H19NSi2—161.39

Residue on ignition (Reagent test): negligible, from [999-97-3]—Clear, colorless liquid.100 mg. Assay—When examined by gas–liquid chromatography, it

Loss on drying ⟨731⟩—Dry it at 105° to constant weight: shows a purity of not less than 95%. The following condi-it loses not more than 10.0% of its weight. tions have been found suitable for assaying the article: A

Hematein, C16H12O6—300.26 [475-25-2]—Prepared 2-mm × 1.8-m glass column packed with phase G3 on sup-from logwood extract or from hematoxylin by treatment port S1. Helium, flowing at a rate of about 40 mL per min-with ammonia and exposure to air. Reddish-brown crystals ute, is the carrier gas; the detector temperature is aboutwith a yellowish-green metallic luster. Very slightly soluble in 310°; the injection port temperature is about 100°; and thewater (about 1 in 1700); slightly soluble in alcohol and in column temperature is programmed to start at 35°, hold forether; insoluble in benzene and in chloroform; freely soluble 5 minutes, then rise at a rate of 8° per minute to 200°. Ain diluted ammonia solution to form a solution of dusky flame-ionization detector is employed.purplish-red color and in an aqueous solution of sodium hy- Residue after evaporation—Transfer 200 g to a tared dish,droxide (1 in 50), to form a solution of bright red color, and evaporate on a steam bath to dryness. Dry the residueviewed in each case through a layer 1 cm in depth. Melts at at 105° for 1 hour, cool, and weigh: not more thana temperature above 200° and tends to decompose at 250°. 0.0025% of residue is found.Hematoxylin (Hydroxybrasilin), C16H14O6 · 3H2O—356.32 Hexamethyleneimine (Homopiperidine), C6H12NH—99.17[517-28-2]—A crystalline substance derived from the heart- [111-49-9]—Colorless to nearly colorless liquid.wood of Haematoxylon campechianum Linne (Fam. Legumi-

Refractive index ⟨831⟩: between 1.4640 and 1.4660 atnosae). Colorless to yellow prisms. Very slightly soluble in20°.cold water and in ether; rapidly soluble in hot water and in

Hexamethylenetetramine—See Methenamine.hot alcohol. When exposed to light, it acquires a red colorn-Hexane, C6H14—86.18 [110-54-3](for use in spectro-and yields a yellow solution. Dissolves in ammonia TS and in

photometry)—Use Hexanes.solutions of alkali hydroxides and carbonates. When dis-Hexane, Solvent (Petroleum Benzin; Petroleum Ether, Lig-solved in solutions of the following salts, it develops the

roin) [8032-32-4]—Clear, volatile liquid. Practically insolublecolors indicated: in alum solution, a red color; in stannousin water; soluble in absolute alcohol. Miscible with ether,chloride solution, a rose color; and in solutions of cupricwith chloroform, with benzene, and with most fixed andsalts, a greenish-gray color. It gradually turns black in potas-volatile oils.sium dichromate solution. Store hematoxylin and its solu-

[CAUTION—It is dangerously flammable. Keep it away fromtions protected from light and air.flames, and store in tight containers in a cool place.]Hemoglobin, Bovine [9008-02-0]—Use a suitable grade.

Use ACS reagent grade Petroleum Ether.Hexane, Solvent, Chromatographic—Use ACS HPLC rea-

gent grade.Hexanes (suitable for use in UV spectrophotometry); usu-

ally a mixture of several isomers of hexane (C6H14), predomi-


nantly n-hexane, and methylcyclopentane (C6H12)—Use ACS Use this grade also for alkoxyl determinations in assays inspectrophotometric reagent grade. the individual monographs.]

Hexanitrodiphenylamine (Dipicrylamine), C12H5N7O12— Hydrobromic Acid, HBr—80.91 [10035-10-6]—Use439.21 [131-73-7]—Yellow-gold powder or prisms. Explo- ACS reagent grade.sive. Usually contains about 15% of water as a safety pre- Hydrochloric Acid, HCl—36.46 [7647-01-0]—Use ACScaution. Insoluble in water, in alcohol, in acetone, and in reagent grade.ether; soluble in glacial acetic acid and in alkalies. Hydrochloric Acid, Diluted (10 percent) [7647-01-0]—

Prepare by mixing 226 mL of hydrochloric acid with suffi-Water, Method I ⟨921⟩: not more than 16%.cient water to make 1000 mL.Hexanophenone, C12H16O—176.25 [942-92-7]—Yel-

Hydrofluoric Acid, HF—20.01 [7664-39-3]—Use ACSlow liquid.reagent grade.Assay—Inject an appropriate specimen into a suitable gas Hydrogen Peroxide, H2O2—34.01 [7722-84-1]—Usechromatograph (see Chromatography ⟨621⟩) equipped with ACS reagent grade with an assay content between 29.0%a flame-ionization detector, helium being used as the carrier and 32.0%.gas. The following conditions have been found suitable: a Hydrogen Peroxide, 10 Percent, H2O2—34.01—Dilute0.25-mm × 30-m capillary column coated with a 1-µm layer 30 mL of 30 percent hydrogen peroxide with water toof phase G3; the injection port temperature is maintained at 100 mL.280°; the detector temperature is maintained at 300°; the Hydrogen Peroxide, 30 Percent, Unstabilized H2O2—column temperature is maintained at 180° and pro- 34.01 [7722-84-1]—Use ACS reagent grade, with an assaygrammed to rise 10° per minute to 280°. The area of the content between 29.0% and 32.0%, without an added sta-C12H16O peak is not less than 98% of the total peak area. bilizer.

Refractive index ⟨831⟩: 1.511 ± 0.002 at 20°. Hydrogen Peroxide, 50 Percent in Water, H2O2—34.01Hexylamine (1-Aminohexane), C6H15N—101.19 [7722-84-1]—Use a suitable grade.

[111-26-2]—Use a suitable grade with a content of not less Hydrogen Peroxide Solution—Use Hydrogen Peroxidethan 99%. Topical Solution.

Histamine Dihydrochloride, C5H9N3 · 2HCl—184.07—Use Hydrogen Sulfide, H2S—34.08 [7783-06-4]—Color-USP Histamine Dihydrochloride RS. less, poisonous gas, heavier than air. Soluble in water. Is

L-Histidine Hydrochloride Monohydrate, C6H9N3O2 · generated by treating ferrous sulfide with diluted sulfuric orHCl · H2O—209.63 [5934-29-2]—Use a suitable grade. diluted hydrochloric acid. Other sulfides yielding hydrogen

Horseradish Peroxidase Conjugated to Goat Anti- sulfide with diluted acids may be used. Is also available inMouse IgG—Affinity purified polyclonal antibody to Mouse compressed form in cylinders.Immune globulin (IgG) heavy and light chains (whole IgG) Hydrogen Sulfide Detector Tube—A fuse-sealed glassproduced in Goat and labeled with horseradish peroxidase. tube so designed that gas may be passed through it andAvailable either as a lyophilized powder or as a solution in a containing suitable absorbing filters and support media forsuitable buffer, generally 10 mM sodium phosphate, pH 7.4, the indicator, the latter consisting of a suitable lead salt.containing a suitable preservative, such as 0.01% thimero- Measuring range: 1 to 20 ppm.sal, and an inactive protein(s) to prevent adsorption on the [NOTE—Available from Draeger Safety, Inc., www.draeger.surface of the container. Use a suitable grade. Store at –20°. com, or from Gastec Corp., www.gastec.co.jp, distributed inHydrazine Dihydrochloride, (NH2)2 · 2HCl—104.97 the USA by www.nextteq.com.][5341-61-7]—White powder. Hydroquinone, C6H4(OH)2—110.11 [123-31-9]—Fine,

Assay—Dissolve about 34 mg, accurately weighed, in colorless or white, needle crystals. Darkens on exposure to50 mL of water. Add carefully while stirring, 1 g of sodium air and light. Soluble in water, in alcohol, and in ether.bicarbonate. [CAUTION—There may be a rapid evolution of Assay—Accurately weigh about 250 mg, and dissolve in acarbon dioxide.] Titrate with 0.1 N iodine solution, deter- mixture of 100 mL of water and 10 mL of 0.1 N sulfuric acidmining the endpoint potentiometrically. Perform a blank de- in a 250-mL conical flask. Add 3 drops of a 1 in 100 solu-termination, and make any necessary corrections. Each mL tion of diphenylamine in sulfuric acid, and titrate with 0.1 Nof 0.1 N iodine solution is equivalent to 2.63 mg of (NH2)2 · ceric sulfate VS until the solution is red-violet in color. Each2HCl. Not less than 98% is found. mL of 0.1 N ceric sulfate is equivalent to 5.506 mg ofHydrazine Hydrate, 85% in Water, (NH2)2 · H2O—50.06 C6H4(OH)2. Not less than 99% is found.[7803-57-8]—Colorless liquid.

Melting range ⟨741⟩: between 172° and 174°.Assay—Transfer 600 mg, accurately weighed, to a Hydroxy Naphthol Blue (1-(2-Naphtholazo-3,6-disulfonic100-mL volumetric flask. Dilute with water to volume, and Acid)-2-naphthol-4-sulfonic Acid, Disodium Salt),mix. Pipet 10 mL into a suitable beaker, and add 1.0 g of C20H12N2O11S3Na2—598.50 [165660-27-5]—Deposited onsodium bicarbonate and 50.0 mL of 0.1 N iodine VS. Titrate crystals of sodium chloride in the concentration of aboutthe excess iodine with 0.1 N sodium thiosulfate VS, using 1%. Use ACS reagent grade.starch TS as the indicator. Perform a blank determination, 3′-Hydroxyacetophenone, C8H8O2—136.15and make any necessary correction. Each mL of 0.1 N io- [121-71-1]—Light brown powder chips and chunks. Meltsdine is equivalent to 1.252 mg of (NH2)2 · H2O. Not less at about 96°. Sparingly soluble in chloroform, yielding athan 83% is found. clear, light yellow solution.Hydrazine Sulfate, (NH2)2 · H2SO4—130.12Assay—Inject an appropriate specimen into a suitable gas[10034-93-2]—Use ACS reagent grade. [CAUTION—Great

chromatograph (see Chromatography ⟨621⟩) equipped withcare should be taken in handling hydrazine sulfate becausea flame-ionization detector, helium being used as the carrierit is a suspected carcinogen.]gas. The following conditions have been found suitable: aHydrindantin (2,2′-Dihydroxy-2,2′-biindan-1,1′,3,3′-tet-0.25-mm × 30-m capillary column coated with G1; the de-rone), C18H10O6—322.27 [5103-42-4]—Sparingly solubletector and the injection port temperatures are maintained atin hot water; soluble in methoxyethanol. When heated300°; the column temperature is maintained at 180° andabove 200°, it becomes reddish brown.programmed to rise 10° per minute to 280° and held atMelting range ⟨741⟩: between 249° and 254°. that temperature for 10 minutes. The area of the main peakHydriodic Acid, HI—127.91 [10034-85-2]—Use ACS is not less than 97% of the total peak area.reagent grade (containing not less than 47.0% of HI). 4′-Hydroxyacetophenone, HOC6H4COCH3—136.15[NOTE—For methoxy determination (see Methoxy Determi- [99-93-4]—Gray powder, melting at about 109°.nation ⟨431⟩), use hydriodic acid ACS reagent grade 55%. p-Hydroxybenzoic Acid, C7H6O3—138.12 [99-96-7]—White crystals.


Assay—Transfer about 700 mg, accurately weighed, to a [94035-02-6]—Use a suitable grade with a substitution de-suitable container, and dissolve in 50 mL of acetone. Add gree between 0.40 and 1.50.100 mL of water, mix, and titrate with 0.5 N sodium hy- 8-Hydroxyquinoline (Oxine), C9H7NO—145.16droxide VS, determining the endpoint potentiometrically. [148-24-3]—Use ACS reagent grade 8-Quinolinol.Perform a blank determination, and make any necessary Hypophosphorous Acid, 50 Percent (Hypophosphorouscorrection. Each mL of 0.5 N sodium hydroxide is equiva- Acid), HPH2O2—66.00 [6303-21-5]—A colorless to faintlylent to 69.06 mg of C7H6O3: not less than 97% is found. yellow liquid. Miscible with water and with alcohol.

Melting range ⟨741⟩: over a range of 2° that includes Assay—Accurately weigh about 4 mL, dilute with 25 mL216°. of water, add methyl red TS, and titrate with 1 N sodium

4-Hydroxybenzoic Acid Isopropyl Ester, hydroxide VS: each mL of 1 N sodium hydroxide is equiva-HOC6H4COOCH(CH2)2—180.18 [4191-73-5]—Use a suit- lent to 66.00 mg of HPH2O2. Not less than 48% is found.

able grade. Chloride—Add 0.2 mL to a mixture of 10 mL of silver ni-[NOTE—A suitable grade is available from TCI America, trate TS and 5 mL of nitric acid, and heat until brown fumes

www.tciamerica.com.] are no longer evolved: any white, insoluble residue remain-Melting range ⟨741⟩: between 84° and 87°. ing is negligible.

2-Hydroxybenzyl Alcohol, C7H8O2—124.14 Phosphate—Dilute 1 mL with water to 50 mL, render al-[90-01-7]—Off-white flakes. Very soluble in alcohol, in chlo- kaline with ammonia TS, filter if a precipitate is formed, androform, and in ether; soluble in 15 parts water and in ben- add to the filtrate 5 mL of magnesia mixture TS: not morezene. than a slight precipitate is formed within 5 minutes.

Assay—Inject an appropriate specimen into a gas chro- Sulfate (Reagent test, Method I)—Dilute 1 mL with watermatograph (see Chromatography ⟨621⟩), equipped with a to 50 mL: 20 mL of the solution shows not more thanflame-ionization detector, helium being used as the carrier 0.2 mg of SO4.gas. The following conditions have been found suitable: a Hypoxanthine, C5H4N4O—136.11 [68-94-0]—White0.25-mm × 30-m capillary column coated with a 1-µm layer to yellowish-white powder. Soluble in 1 N sodium hydrox-of phase G2; the injection port temperature is maintained at ide. Use a suitable grade.250°; the detector temperature is maintained at 300°; and IgG-Coated Red Cells—Red cells coated with human im-the column temperature is maintained at 150° and pro- munoglobulin (IgG). The reagent must be obtained fromgrammed to rise 10° per minute to 280°. The area of the manufacturers or suppliers licensed by the Center for Bio-C7H8O2 peak is not less than 99% of the total peak area. logics Evaluation and Research, Food and Drug Administra-

Melting range ⟨741⟩: between 83° and 85°. tion. The use of reagents from an unlicensed manufacturer4-Hydroxybutane-1-sulfonic Acid (4-Hydroxy- or supplier may invalidate the results.

1-butanesulfonic Acid), C4H10O4S—154.19 [26978-64-3]— [NOTE—There are many manufacturers and suppliers ofUse a suitable grade with a content of NLT 95%. [NOTE—A these reagents that are licensed by the Center for Biologicssuitable grade is available as catalog number RM-967-C50 Evaluation and Research, Food and Drug Administration.from www.cydexpharma.com.] Some examples of licensed manufacturers or suppliers are

N-(2-Hydroxyethyl)piperazine-N’-(2-ethanesulfonic the following: Gamma Biologics, Houston, TX; and Orthoacid), C8H18N2O4S—238.3 [7365-45-9]—Use a suitable Diagnostics, Raritan, NJ.]grade. Imidazole, C3H4N2—68.08 [288-32-4]—White to light

Hydroxylamine Hydrochloride, NH2OH · HCl—69.49 yellow crystals. Freely soluble in water. Use ACS reagent[5470-11-1]—Use ACS reagent grade. grade.

10β-Hydroxynorandrostenedione (10β-Hydroxy- Indene, C9H8—116.16 [95-13-6]—Colorless liquid.19-norandrost-4-ene-3,17-dione), C18H24O3—288.38—Use a Assay—Inject an appropriate specimen into a suitable gassuitable grade. chromatograph (see Chromatography ⟨621⟩) equipped with

4-(4-Hydroxyphenyl)-2-butanone, C10H12O2—164.20 a flame-ionization detector, helium being used as the carrier[5471-51-2]—White powder. gas. The following conditions have been found suitable: a

Assay—Inject an appropriate volume into a gas chromat- 0.25-mm × 10-m capillary column coated with a 1-µm layerograph (see Chromatography ⟨621⟩) equipped with a flame- of methylsilicone; the injection port temperature is main-ionization detector, helium being used as the carrier gas. tained at 200°; the detector temperature is maintained atThe following conditions have been found suitable: a 0.25- 300°; the column temperature is maintained at 100° andmm × 30-m capillary column coated with a 1-µm layer of programmed to rise 10° per minute to 250°. The area ofphase G43; the injection port temperature is maintained at the indene peak is not less than 99% of the total peak area.280°; the detector temperature is maintained at 300°; the Refractive index ⟨831⟩: between 1.5749 and 1.5769 atcolumn temperature is maintained at 180° and pro- 20°.grammed to rise 10° per minute to 280°. The area of the Indicators—See separate subsection.C10H12O2 peak is not less than 98.5% of the total peak area. Indigo Carmine—Use Indigotindisulfonate Sodium.

Melting range ⟨741⟩: between 81° and 87°. Indole (2,3-Benzopyrrole), C8H7N—117.143-Hydroxyphenyldimethylethyl Ammonium Chloride [120-72-9]—Use a suitable grade.

[Dimethylethyl(3-hydroxyphenyl)ammonium Chloride]—Use Indole-3-carboxylic Acid, C9H7NO2—161.2Edrophonium Chloride. [771-50-6]—Use a suitable grade.

D-α-4-Hydroxyphenylglycine, C8H9NO3—167.16 Inosine, C10H12N4O5—268.23 [58-63-9]—White, crys-[22818-40-2]—Shiny leaflets. Sparingly soluble in water, in talline powder.alcohol, in acetone, in ether, in chloroform, in ethyl acetate, Melting point ⟨741⟩: about 90°.in benzene, and in glacial acetic acid; soluble in alkalies and Inositol (Hexahydroxycyclohexane), C6H6(OH)6—180.16in mineral acids; freely soluble in warm 20% v/v hydrochlo- [87-89-8]—Fine, white crystals or a white, crystalline pow-ric acid. der; stable in air. Its solutions are neutral to litmus. Optically

Melting range ⟨741⟩: between 220° and 247°, with de- inactive. One g dissolves in 5.7 mL of water. Slightly solublecomposition. in alcohol; insoluble in ether and in chloroform. Store in

2′-(4-Hydroxyphenyl)-5-(4-methyl-1-piperazinyl)-2,5′-bi- well-closed containers.1H-benzimidazole Trihydrochloride Pentahydrate—623.97 [23491-44-3]—Dark yellow to tan powder with agreen cast. Use a suitable grade.

Hydroxypropyl-β-cyclodextrin (Hydroxypropylbetadex),C42H70O35(C3H6O)x with x = 7 molar substitution


Melting range ⟨741⟩: between 223° and 226°. Specific gravity ⟨841⟩: between 0.863 and 0.868.Loss on drying ⟨731⟩—Dry it at 105° for 4 hours: it loses Refractive index ⟨831⟩: between 1.3900 and 1.3920 at

not more than 0.5% of its weight. 20°.Isobutyl Alcohol (2-Methyl-1-propanol),Residue on ignition (Reagent test): not more than 0.1%.

(CH3)2CHCH2OH—74.12 [78-83-1]—Use ACS reagentIobenguane Sulfate (m-Iodobenzylguanidine Hemisulfategrade.Salt), C8H10IN3 · 1/2H2SO4—324.1—White powder. Freely sol-

4-Isobutylacetophenone, C12H16O—176—Pale yellow liq-uble in methanol.uid. Soluble in chloroform, in glycerols, in alcohols, in ether,Assay—When tested by thin-layer chromatography, with and in fatty oils; insoluble in water. Use a suitable grade.the use of plates coated with chromatographic silica gel [NOTE—A suitable grade is available from TCI America,mixture, a developing system consisting of a mixture of bu- www.tciamerica.com.]tyl alcohol, water, and acetic acid (60:25:15), and examined N-Isobutylpiperidone, C9H17NO—155.24—Use a suitableunder short-wavelength UV light, not more than a single grade.impurity spot of not more than 0.5% is observed. Isoflupredone Acetate (9-α-Fluoroprednisolone Acetate),Iodic Acid, HIO3—175.91 [7782-68-5]—Use ACS rea- C23H29FO6—420.47—Use Isoflupredone Acetate USP.gent grade. Isomaltotriose (α-D-Glucosyl-(1-6)-α-D-glucosyl-(1-6)-α-D-Iodine, I2—253.81 [7553-56-2]—Use ACS reagent glucose), C18H32O16—504.4 [3371-50-4]—White lyophi-grade. lized powder. Use a suitable grade.Iodine Monobromide, IBr—206.81 [7789-33-5]— Isonicotinic Acid, C6H5NO2—123.11 [52-22-1]—Use aBlack, gray, or blue-purple crystals, crystalline needles, or suitable grade.crystalline chunks. Isonicotinic Acid Hydrazide—Use Isoniazid.

Assay—Place about 100 mL of acetic acid in a 150-mL Isooctane—See 2,2,4-Trimethylpentane.beaker. Separately dissolve 2 g of potassium iodide in a min- Isopropyl Acetate, C5H10O2—102.13 [108-21-4]—Useimum volume of water, add this solution to the acetic acid, a suitable grade.and mix. Transfer about 200 mg of Iodine Monobromide, Isopropyl Alcohol (2-Propanol), (CH3)2CHOH—60.10accurately weighed, to the beaker containing the potassium [67-63-0]—Use ACS reagent grade.iodide and acetic acid mixture, and stir to dissolve. Titrate [NOTE—For use in assays and tests involving UV spectro-immediately with 0.1 N sodium thiosulfate VS, determining photometry, use ACS reagent grade Isopropyl Alcohol Suita-the endpoint potentiometrically (see Titrimetry ⟨541⟩). Per- ble for Use in UV Spectrophotometry.]form a blank determination, and make any necessary correc- Isopropyl Alcohol, Dehydrated [67-63-0]—Use Isopropyltion. Each mL of 0.1 N sodium thiosulfate is equivalent to Alcohol that previously has been dried by being shaken with20.681 mg of IBr. Not less than 97.5% is found. a suitable molecular sieve capable of adsorbing water, and

Iodine Monochloride, ICl—162.36 [7790-99-0]—Use filtered.ACS reagent grade. Isopropyl Ether—See Diisopropyl Ether.

Iodoethane, C2H5I—155.9 [75-03-6]—Use a suitable Isopropyl Iodide (2-Iodopropane), C3H7I—169.99grade. [75-30-9]—Use a suitable grade.

p-Iodonitrotetrazolium Violet, (2-(4-Iodophenyl)-3-(4-ni- Isopropyl Myristate, C17H34O2—270.45 [110-27-0]—trophenyl)-5-phenyltetrazolium chloride), C19H13ClIN5O2— Use Isopropyl Myristate (NF monograph). For use as a sol-505.70—Light yellow powder. vent in sterility test procedures, Isopropyl Myristate con-

Assay—When tested by thin-layer chromatography, with forms to the following additional specification:the use of plates coated with chromatographic silica gel pH of water extract—Transfer 100 mL to a 250-mL centri-mixture and a developing system consisting of a mixture of fuge bottle, add 10 mL of twice-distilled water, close theamyl alcohol, formic acid, and water (8:1:1), sprayed with bottle with a suitable closure, and shake vigorously for0.1% sodium thiosulfate solution, and examined under 60 minutes. Centrifuge the mixture at 1800 rpm for 20 min-short-wavelength UV light, a single spot is exhibited, with utes, aspirate the upper (isopropyl myristate) layer, and de-trace impurities. termine the pH of the residual water layer: the pH is not less

Melting point ⟨741⟩: 240°, with decomposition. than 6.5.Ion-Exchange Resin—An intimate mixture of 4 parts of a Isopropyl Myristate not conforming to the test for pH of

strongly acidic cation-exchanger in the hydrogen form (pro- water extract may be rendered suitable for use in sterilityduced by sulfonation of a styrene-divinylbenzene copolymer, test procedures as follows:representing 8 to 10% divinylbenzene) and 6 parts of a Using a 20-mm × 20-cm glass column, add activated alu-strongly basic anion-exchanger in the hydroxyl form (pro- mina, and tamp down to a height of 15 cm. Pass 500 mL ofduced by amination with trimethylamine of a chlorometh- the isopropyl myristate through the column, using a slightylated styrene-divinylbenzene copolymer, representing 3 to positive pressure to maintain an even flow, and use the elu-5% divinylbenzene). ate collected directly in the sterility test procedure.

[NOTE—A suitable resin is “Amberlite MB-150,” available Isopropyl Salicylate, C6H4OHCOOCH(CH3)2—180.20—from Sigma-Aldrich, www.sigma-aldrich.com.] Colorless liquid.

Iron Wire, Fe—At. Wt. 55.847—Use a suitable grade. Assay—Inject an appropriate specimen into a suitable gasIsoamyl Alcohol—Use Amyl Alcohol. chromatograph (see Chromatography ⟨621⟩) equipped withIsobutyl Acetate, C6H12O2—116.16 [110-19-0]—Clear, a flame-ionization detector, helium being used as the carrier

colorless liquid. Slightly soluble in water. Miscible with alco- gas. The following conditions have been found suitable: ahol. 2-mm × 1.8-m glass column packed with 7% phase G2 on

Assay—Inject an appropriate specimen into a suitable gas support S1A; the injection port temperature is maintained atchromatograph (see Chromatography ⟨621⟩) equipped with 250°; the detector temperature is maintained at 310°; thea flame-ionization detector, helium being used as the carrier column temperature is maintained at 50° and programmedgas. The following conditions have been found suitable: a to rise 10° per minute to 250°. The area of the main peak is0.25-mm × 30-m capillary column coated with G2. The innot less than 97% of the total peak area.jection port temperature is maintained at 130°; the column Isopropylamine (2-Aminopropane), C3H7NH2—59.11temperature is maintained at 30° and programmed to rise [75-31-0]—Clear, colorless, flammable liquid. Miscible with10° per minute to 180° and held there for 10 minutes. The water, with alcohol, and with ether.detector temperature is maintained at 300°. The area of the Assay—Transfer about 0.2 g, accurately weighed, to amain peak is not less than 99% of the total peak area. suitable container, add 50 mL of water, and mix. Titrate

with 0.1 N hydrochloric acid VS, using a mixture of bromo-cresol green TS and methyl red TS (5:1) as indicator. Each


mL of 0.1 N hydrochloric acid is equivalent to 59.11 mg of acid and lead acetate TS (1:10). Remove, dry, and cut intoC3H9N. Not less than 98% is found. 15-mm × 40-mm strips.

Lead Monoxide (Litharge), PbO—223.20Boiling range (Reagent test)—Not less than 95% distills[1317-36-8]—Heavy, yellowish or reddish-yellow powder. In-between 31° and 33°.soluble in water and in alcohol; soluble in acetic acid, inRefractive index ⟨831⟩: between 1.3743 and 1.3753, at diluted nitric acid, and in warm solutions of the fixed alkali20°. hydroxides.Isorhamnetin, C16H12O7—316.27 [418-19-3]—Yellow

Assay—Accurately weigh about 300 mg, freshly ignited inpowder.a muffle furnace at 600 ± 50°, and dissolve it by warmingMelting point: greater than 300°. with 10 mL of water and 1 mL of glacial acetic acid. DiluteIsovaleric Acid (3-Methylbutanoic Acid, Isovalerianic Acid, with 75 mL of water, heat to boiling, add 50.0 mL of 0.1 NIsopropylacetic Acid), C5H10O2—102.13 [503-74-2]—Use a potassium dichromate VS, and boil for 2 to 3 minutes. Cool,suitable grade. transfer to a 200-mL volumetric flask with the aid of water,Kaempferol, C15H10O6—286.24 [520-18-3]—Light yel- dilute with water to volume, mix, and allow to settle. With-low to yellow powder. It is a clear, bright yellow solution in draw 100.0 mL of the clear liquid, and transfer to a glass-alcohol. stoppered flask. Add 10 mL of diluted sulfuric acid and 1 gKerosene [8008-20-6]—A mixture of hydrocarbons, of potassium iodide, insert the stopper, mix gently, and al-chiefly of the methane series. A clear, colorless liquid. Spe- low to stand for 10 minutes. Then titrate the liberated io-cific gravity: about 0.80. Distills between 180° and 300°. dine, representing the excess of dichromate, with 0.1 N so-L Designations—See packings for high-pressure liquid dium thiosulfate VS, adding 3 mL of starch TS as thechromatography under Reagents, Chromatographic Columns. endpoint is approached: each mL of 0.1 N potassiumLactose, C12H22O11 · H2O—360.31 [64-42-3]—Use ACS dichromate is equivalent to 7.440 mg of PbO. Not less thanreagent grade. 98% is found.Alpha Lactose Monohydrate (α-D-Lactose Monohydrate),

Insoluble in acetic acid—Dissolve 2 g in 30 mL of diluteC12H22O11 · H2O—360.31—White powder. The β-D-lactoseglacial acetic acid (1 in 2), boil gently for 5 minutes, filter,content is less than 3%.wash the residue with diluted acetic acid, and dry at 105°Assay—Inject an appropriate derivatized specimen into a for 2 hours: the residue weighs not more than 10 mggas chromatograph (see Chromatography ⟨621⟩) equipped (0.5%).with a flame-ionization detector, helium being used as the

Substances not precipitated by hydrogen sulfide—Com-carrier gas. The following conditions have been found suita-pletely precipitate the lead from the filtrate obtained in theble: a 0.25-mm × 30-m capillary column coated with atest for Insoluble in acetic acid by passing hydrogen sulfide1-µm layer of phase G2; the injection port temperature isinto it, filter, and wash the precipitate with 20 mL of water.maintained at 250°; the detector temperature is maintainedTo one-half of the mixed filtrate and washings add 5 dropsat 280°; the column temperature is maintained at 230° andof sulfuric acid, evaporate to dryness, and ignite atprogrammed to rise 4° per minute to 280°. The area of the800 ± 25° for 15 minutes: the residue weighs not more thanC12H22O11 · H2O peak is not less than 97% of the total peak5 mg (0.5%).area.

Beta Lactose (β-D-Lactose), C12H22O11—342.30—White to Volatile substances—Accurately weigh about 5 g, and heatfaint yellow powder. The α-D-lactose content is not more strongly in a covered porcelain crucible: it loses not morethan 35%. than 2.0% of its weight.

Lead Nitrate, Pb(NO3)2—331.21 [10099-74-8]—UseAssay—Inject an appropriate derivatized specimen into aACS reagent grade.gas chromatograph (see Chromatography ⟨621⟩) equipped

Lead Perchlorate, Pb(ClO4)2 · 3H2O—460.15—Use ACSwith a flame-ionization detector, helium being used as thereagent grade.carrier gas. The following conditions have been found suita-

Lead Tetraacetate, C8H12O8Pb—443.38 [546-67-8]—ble: a 0.25-mm × 30-m capillary column coated with aColorless to pinkish crystals. Soluble in hot glacial acetic1-µm layer of phase G43; the injection port temperature isacid, in chloroform, in nitrobenzene, and in tetrachloroeth-maintained at 250°; the detector temperature is maintainedane. Hydrolyzed by water, producing brown lead dioxideat 250°; the column temperature is maintained at 20° andand acetic acid. Unstable in air.programmed to rise 8° per minute to 280°. The area of the

C12H22O11 peak is not less than 99% of the total peak area. Melting range ⟨741⟩: between 175° and 180°.Lanthanum Alizarin Complexan Mixture—Use a suitable Linalool (3,7-Dimethyl-1,6-octadien-3-ol), C10H18O—

grade. 154.25 [78-70-6]—Use a suitable grade.Lanthanum Chloride, LaCl3 · (6–7)H2O [10025-84-0]— Linoleic Acid, C18H32O2—280.4 [60-33-3]—Clear, col-

This reagent is available in degrees of hydration ranging orless liquid. Use a suitable grade.from 6 to 7 molecules of water. Use ACS reagent grade. α-Lipoic Acid, C8H14O2S2—206.3 [1077-28-7]—Yellow

Lanthanum Nitrate Hexahydrate, La(NO3)3 · 6H2O— powder. Use a suitable grade.433.01 [10277-43-7]—Use a suitable grade with a con- Liquid Petrolatum—Use Mineral Oil.tent of NLT 99.9%. Lithium Chloride, LiCl—42.39 [7447-41-8]—Use ACS

Lanthanum Oxide, La2O3—325.82 [1312-81-8]—An reagent grade.almost white, amorphous powder, practically insoluble in Lithium Hydroxide, LiOH · H2O—41.96 [1310-65-2]—water. It dissolves in dilute solutions of mineral acids and Use ACS reagent grade.absorbs atmospheric carbon dioxide. Use Atomic Absorption Lithium Metaborate, LiBO2—49.75 [13453-69-5]—Spectroscopy grade. Use ACS reagent grade.

Lauryl Dimethyl Amine Oxide (N,N-Dimethyldodecyl- Lithium Nitrate, LiNO3—68.95 [7790-69-4]—Colorlessamine-N-oxide),C14H31NO [1643-20-5]—229.41—Use a suita- crystals. Use a suitable grade labeled to contain not lessble grade. than 97.0%.

[NOTE—A suitable grade is available from Fluka, catalog Lithium Perchlorate, LiClO4—106.39 [7791-03-9]—number 40234, www.sigma-aldrich.com.] Use ACS reagent grade.

Lead Acetate, Pb(C2H3O2)2 · 3H2O—379.33 Lithium Sulfate, Li2SO4 · H2O—127.96 [10377-48-7]—[6080-56-4]—Use ACS reagent grade. Use ACS reagent grade.

Lead Acetate Paper—Immerse filter paper weighing Lithocholic Acid, C24H40O3—376.57 [434-13-9]—about 80 g per square meter in a mixture of diluted acetic White powder.

Assay—When tested by thin-layer chromatography, withthe use of plates coated with chromatographic silica gel


mixture, a developing system consisting of a mixture of tol- while still warm to tight containers, as the anhydrous salt isuene, 1,4-dioxane, and acetic acid (15.2:4.2:0.6), and very hygroscopic.sprayed with a mixture of sulfuric acid and methanol (1:1), Malachite Green G—See Brilliant Green.heated at 110° for 20 minutes, and examined visually and Maleic Acid, C4H4O4—116.07 [110-16-7]—White, crys-under long-wavelength UV light, a single spot is exhibited. talline powder. Soluble in 1.5 parts of water, in 2 parts of

alcohol, and in 12 parts of ether.Melting range ⟨741⟩: between 184° and 186°.Litmus [1393-92-6]—A blue pigment prepared from vari- Assay—Dissolve about 2 g, accurately weighed, in

ous species of Rocella DeCandolle, Lecanora Acharius, or 100 mL of water and titrate with 1 N sodium hydroxide VS,other lichens (Fam. Parmeliaceae). using phenolphthalein TS as the indicator. Each mL of 1 N

sodium hydroxide is equivalent to 58.04 mg of C4H4O4: notDescription—Cubes, masses, fragments, or granules, of anless than 99% of C4H4O4, calculated on the dried basis, isindigo blue or deep violet color. Has the combined odor offound.indigo and violets, and tinges the saliva a deep blue. The

indicator substances it contains are soluble in water and less Loss on drying—Dry it in vacuum over phosphorus pent-soluble or insoluble in alcohol. oxide for 2 hours: it loses not more than 1.5% of its weight.

Ash—It yields not more than 60.0% of ash. Residue on ignition ⟨281⟩: not more than 0.1%.Locust Bean Gum—A gum obtained from the ground en- Maltotriose, C18H32O16—504.44 [1109-28-0]—Use a

dosperms of Ceratonia siliqua Linne Taub. (Fam. Legumi- suitable grade with a content of not less than 95%.nosae). Use Locust Bean Gum, FCC. Manganese Dioxide—See Manganese Dioxide, Activated.

L-Lysine (2,6-Diaminohexanoic Acid), C6H14N2O2—146.19 Manganese Dioxide, Activated (Manganese (IV) Oxide,[56-87-1]—Crystalline needles or hexagonal plates. Soluble Activated), MnO2—86.94 [1313-13-9]—Use a suitablein water; very slightly soluble in alcohol; insoluble in ether. grade.

Melamine (2,4,6-Triamino-1,3,5-triazine), C3H6N6—126.1Specific rotation ⟨781⟩: between +25.5° and +26.0°.[108-78-1]—Use a suitable grade.Test solution: 20 mg per mL, in dilute hydrochloric acid 2-Mercaptoethanol (β-Mercaptoethanol), C2H6OS—(1 in 2). 78.13 [60-24-2]—Use a suitable grade.

Nitrogen content, Method I ⟨461⟩: between 18.88% and Mercuric Acetate, Hg(C2H3O2)2—318.6819.44% of N is found, corresponding to not less than [1600-27-7]—Use ACS reagent grade.98.5% of C6H14N2O2, the test specimen previously having Mercuric Bromide, HgBr2—360.40 [7789-47-1]—Usebeen dried at 105° for 2 hours. ACS reagent grade.

Magnesium, Mg—24.305 [7439-95-4]—Silvery metal Mercuric Chloride, HgCl2—271.50 [7487-94-7]—Usein ribbon form. Reacts slowly with water at room tempera- ACS reagent grade.ture. Dissolves readily in dilute acids with the liberation of Mercuric Iodide, Red, HgI2—454.40 [7774-29-0]—Usehydrogen. ACS reagent grade.

Assay—Transfer 1 g, accurately weighed, to a 250-mL vol- Mercuric Nitrate, Hg(NO3)2 · xH2O—342.62umetric flask, and dissolve in a mixture of 15 mL of hydro- [10045-94-0]—Use ACS reagent grade. This reagent is avail-chloric acid and 85 mL of water. When solution is complete, able as either the mono- or dihydrate.dilute with water to volume, and mix. Pipet 25 mL of the Mercuric Oxide, Yellow, HgO—216.59dilution into a 400-mL beaker, dilute with water to 250 mL, [21908-53-2]—Use ACS reagent grade.add 20 mL of ammonia–ammonium chloride TS and a few Mercuric Sulfate, HgSO4—296.65 [7783-35-9]—Usemg of eriochrome black T trituration, and titrate with 0.1 M ACS reagent grade.edetate disodium VS to a blue endpoint. Each mL of 0.1 M Mercuric Thiocyanate, Hg(SCN)2—316.76edetate disodium VS is equivalent to 2.430 mg of Mg. Not [592-85-8]—White, crystalline powder. Very slightly solubleless than 99% is found. in water; soluble in solutions of sodium chloride; slightly sol-

Magnesium Acetate, Mg(C2H3O2)2 · 4H2O—214.45 uble in alcohol and in ether.[142-72-3]—Use ACS reagent grade. Mercurous Nitrate Dihydrate (Mercury (I) Nitrate

Magnesium Chloride, MgCl2 · 6H2O—203.30 Dihydrate), Hg2(NO3)2 · 2H2O—561.22—Use ACS reagent[7786-30-3]—Use ACS reagent grade. grade.

Magnesium Nitrate, Mg(NO3)2 · 6H2O—256.41 Mercury, Hg—At. Wt. 200.59 [7439-97-6]—Use ACS[10377-60-3]—Use ACS reagent grade. reagent grade.

Magnesium Oxide, MgO—40.30 [1309-48-4]—Use Mesityl Oxide, C6H10O—98.14 [141-79-7]—ColorlessACS reagent grade. liquid.

Magnesium Oxide, Chromatographic—Use a suitable Assay—Inject an appropriate specimen into a suitable gasgrade. chromatograph (see Chromatography ⟨621⟩) equipped with

Magnesium Perchlorate, Anhydrous, Mg(ClO4)2— a flame-ionization detector, helium being used as the carrier223.21 [10034-81-8]—Use ACS reagent grade. gas. The following conditions have been found suitable: a

Magnesium Silicate, Activated—Use a suitable grade. 0.25-mm × 30-m capillary column coated with a 1-µm layerMagnesium Silicate, Chromatographic—Extremely of phase G2; the injection port temperature is maintained at

white, hard, powdered (60- to 100-mesh) magnesia–silica 150°; the detector temperature is maintained at 300°; thegel. Suitable for use as an adsorbant in column chromatog- column temperature is maintained at 50° and programmedraphy. to rise 10° per minute to 200°. The area of the C6H10O peak

Magnesium Sulfate, MgSO4 · 7H2O—246.48 is not less than 98% of the total peak area.[10034-99-8]—Use ACS reagent grade. Refractive index ⟨831⟩: between 1.443 and 1.447 at 20°.Magnesium Sulfate, Anhydrous, MgSO4—120.37 Metanil Yellow (Acid Yellow 36;[7487-88-9]—Anhydrous Magnesium Sulfate may be pre- 3-(4-Anilinophenylazo)benzenesulfonic Acid Sodium Salt), pared as follows. Place a suitable quantity of magnesium C18H14N3NaO3S—375.38 [587-98-4]—Use a suitable gradesulfate (see above), preferably powdered, in a shallow ves- with a dye content of NLT 70%.sel, and expose to a temperature of about 80° for several Metaphenylenediamine Hydrochloride (Metaphenylene-hours with occasional stirring. Then heat at 275° to 300° diamine Dihydrochloride), C6H4(NH2)2 · 2HCl—181.06—Whiteuntil the weight is practically constant. Transfer the product or slightly reddish-white, crystalline powder. Easily soluble in

water. On exposure to light it acquires a reddish color.Store it protected from light.

Solubility—A solution of 1 g in 200 mL of water is color-less.


Residue on ignition (Reagent test)—Ignite 1 g with 0.5 mL tion. Each mL of 0.1 N perchloric acid is equivalent toof sulfuric acid: the residue weighs not more than 1 mg 15.12 mg of C8H9NO2. Not less than 99.0% is found.(0.1%). Melting range ⟨741⟩: between 108° and 110°.

[NOTE—Metaphenylenediamine hydrochloride solution can Methyl Arachidate (Eicosanoic acid, methyl ester),be decolorized by treatment with a small quantity of acti- C21H42O2—326.56 [1120-28-1]—Off-white flakes.vated charcoal.] Assay—Inject an appropriate specimen into a gas chro-Metaphosphoric Acid (Vitreous Sodium Acid Metaphos- matograph (see Chromatography ⟨621⟩) equipped with aphate), HPO3—79.98 [37267-86-0]—Use ACS reagent thermal-conductivity detector, helium being used as the car-grade. rier gas. The following conditions have been found suitable:Methacrylic Acid [79-41-4]—Use a suitable grade. a 2.0-mm × 1.8-m glass column packed with 5% G2 phaseMethanesulfonic Acid, CH4O3S—96.11 [75-75-2]— on support S1A; the injection port temperature is main-Use a suitable grade. tained at 300°; the detector temperature is maintained atMethanol (Methyl Alcohol), CH3OH—32.04 300°; the column temperature is maintained at 230° and[67-56-1]—Use ACS reagent grade. programmed to rise 3° per minute to 280°. The area of theMethanol, Aldehyde-Free, CH3OH—32.04—Dissolve C2H42O2 peak is not less than 99% of the total peak area.25 g of iodine in 1 L of methanol and pour the solution,

Melting range ⟨741⟩: between 46° and 51°.with constant stirring, into 400 mL of 1 N sodium hydrox-Methyl Behenate, C23H46O2—354.61 [929-77-1]—ide. Add 150 mL of water, and allow to stand for 16 hours.

White powder.Filter, and boil under a reflux condenser until the odor ofAssay—Inject an appropriate specimen into a gas chro-iodoform disappears. Distill the solution by fractional distilla-

matograph (see Chromatography ⟨621⟩) equipped with ation. It contains not more than 0.001% of aldehydes andthermal conductivity detector, helium being used as the car-ketones.rier gas. The following conditions have been found suitable:Methanol, Anhydrous—Use Methanol.a 2.0-mm × 1.8-m glass column packed with 5% G3 phaseMethanol, Spectrophotometric—Use ACS reagent gradeon support S1A; the injection port temperature is main-Methanol Suitable for Use in UV Spectrophotometry.tained at 300°; the detector temperature is maintained atMethenamine (Hexamethylenetetramine; Urotropine;300°; the initial temperature of the oven is 220°, which isUritone; Hexamine), C6H12N4—140.19 [100-97-0]—Useheld for 2 minutes, and then programmed to rise 3° perACS reagent grade Hexamethylenetetramine.minute to attain a final temperature of 270°, which is held7-Methoxycoumarin (Herniarin; Methyl Umbelliferylfor 10 minutes. The area of the C23H46O2 peak is not lessEther), C10H8O3—176.17 [531-59-9]—Use a suitable gradethan 98% of the total peak area.with a content of not less than 98%.

Methoxyethanol (Ethylene Glycol Monomethyl Ether; Melting range ⟨741⟩: between 54° and 56°.2-Methoxyethanol), CH3OCH2CH2OH—76.09 Methyl Benzenesulfonate, C7H8O3S—172.20[109-86-4]—Use ACS reagent grade. [80-18-2]—Use a suitable grade.

2-Methoxyethanol (Ethylene Glycol Monomethyl Ether; Methyl Caprate, C11H22O2—186.29 [110-42-9]—Col-Methoxyethanol), CH3OCH2CH2OH—76.09 [109-86-4]— orless liquid.See Methoxyethanol. Assay—Inject an appropriate volume into a gas chromat-

ograph (see Chromatography ⟨621⟩) equipped with a flame-ionization detector, helium being used as the carrier gas.Add the following:The following conditions have been found suitable: a 0.25-mm × 30-m capillary column coated with a 1-µm layer of▲ 5-Methoxy-1H-benzimidazole-2-thiol (5-Methoxy-phase G2; the injection port temperature is maintained at2-benzimidazolethiol), C8H8N2OS—180.23 [37052-78-1]—250°; the detector temperature is maintained at 300°; theUse a suitable grade with a content of NLT 99.0%.▲ USP36 column temperature is maintained at 150° and pro-5-Methoxy-2-methyl-3-indoleacetic Acid, C12H13NO3— grammed to rise 10° per minute to 280°. The area of the219.24 [2882-15-7]—Off-white powder.C11H22O2 peak is not less than 98.5% of the total peak area.Assay—Transfer about 110 mg, accurately weighed, to a Methyl Caprylate, C9H18O2—158.24 [111-11-5]—Col-100-mL beaker. Add 30 mL of methanol and dissolve by stir- orless liquid.ring. Add 40 mL of water, and mix. Titrate with 0.1 N so-

Assay—Inject an appropriate volume into a gas chromat-dium hydroxide VS, determining the endpoint potentiomet-ograph (see Chromatography ⟨621⟩) equipped with a flame-rically. Perform a blank determination and make anyionization detector, helium being used as the carrier gas.necessary correction. Each mL of 0.1 N sodium hydroxide isThe following conditions have been found suitable: a 0.25-equivalent to 21.92 mg of C12H13NO3. Not less than 98% ismm × 30-m capillary column coated with a 1-µm layer offound.phase G2; the injection port temperature is maintained atMelting range ⟨741⟩: between 161° and 168°, but the 230°; the detector temperature is maintained at 300°; therange between beginning and end of melting does not ex- column temperature is maintained at 130° and pro-ceed 3°. grammed to rise 10° per minute to 280°. The area of theMethoxyphenylacetic Acid (α-Methoxyphenylacetic Acid), C9H18O2 peak is not less than 98.5% of the total peak area.C9H10O3—166.2 [7021-09-2]—Use a suitable grade. Methyl Carbamate, C2H5NO2—75.07 [598-55-0]—Methyl Acetate, C3H6O2—74.08 [74-20-9]—Colorless White crystals. Freely soluble in water.liquid. Soluble in water. Miscible with alcohol and with

Melting range ⟨741⟩: between 54° and 56°.ether.Methyl Chloroform (Methylchloroform; 1,1,Specific gravity ⟨841⟩: about 0.933. 1-Trichloroethane), CH3CCl3—133.40 [71-55-6]—Use ACS

Refractive index ⟨831⟩: between 1.3615 and 1.3625 at reagent grade.20°. Methyl Erucate, C23H44O2—352.59 [1120-34-9]—Col-

Boiling range (Reagent test)—Not less than 95% distills orless liquid.between 57° and 58°. Methyl Ethyl Ketone, CH3COC2H5—72.11 [78-93-3]—

Methyl 4-Aminobenzoate, C8H9NO2—151.16 Use ACS reagent grade 2-butanone.[619-45-4]—Off-white powder. Methyl Green (Methyl Green Zinc Chloride Double Salt;

Ethyl Green Zinc Chloride Double Salt; C.I. 42590),Assay—Dissolve about 38 mg, accurately weighed, inC27H35Cl2N3 · ZnCl2—608.78 [7114-03-6]—Use a suitable50 mL of glacial acetic acid. Titrate with 0.1 N perchloricgrade for microscopy.acid VS, determining the endpoint potentiometrically. Per-

Methyl Heptadecanoate, C18H36O2—284.48form a blank determination, and make any necessary correc-[1731-92-6]—White, crystalline flakes.


Assay—Inject an appropriate specimen into a gas chro- Assay—Inject an appropriate volume into a gas chromat-matograph (see Chromatography ⟨621⟩) equipped with a ograph (see Chromatography ⟨621⟩) equipped with a flame-flame-ionization detector, helium being used as the carrier ionization detector, helium being used as the carrier gas.gas. The following conditions have been found suitable: a The following conditions have been found suitable: a 0.25-0.25-mm × 30-m capillary column coated with a 1-µm layer mm × 30-m capillary column coated with a 1-µm layer ofof phase G8; the injection port temperature is maintained at phase G2; the injection port temperature is maintained at220°; the detector temperature is maintained at 220°; the 300°; the detector temperature is maintained at 300°; thecolumn temperature is maintained at 180° and pro- column temperature is maintained at 200° and pro-grammed to rise 4° per minute to 220°. The area of the grammed to rise 10° per minute to 300°. The area of theC18H36O2 peak is not less than 99% of the total peak area. C15H30O2 peak is not less than 99% of the total peak area.

Melting range ⟨741⟩: between 31° and 32°. Refractive index ⟨831⟩: between 1.434 and 1.438 at 20°.Methyl Iodide, (Iodomethane), CH3I—141.94 Methyl Oleate, C19H36O2—296.49 [112-62-9]—Color-

[74-88-4]—Colorless, heavy, transparent liquid. Slightly solu- less liquid.ble in water. Miscible with alcohol, with ether, and with Assay—Inject an appropriate specimen into a suitable gassolvent hexane. Turns brown on exposure to light as a result chromatograph (see Chromatography ⟨621⟩) equipped withof liberation of iodine. a flame-ionization detector, helium being used as the carrier

Use a suitable grade with a content of not less than 99%. gas. The following conditions have been found suitable: aMethyl Isobutyl Ketone—See 4-Methyl-2-pentanone. capillary column coated with a 1-µm layer of phase G2; theMethyl Laurate, C13H26O2—214.34 [110-82-0]—Color- injection port temperature is maintained at 300°; the detec-

less liquid. tor temperature is maintained at 300°; the column tempera-Assay—Inject an appropriate volume into a gas chromat- ture is maintained at 230° and programmed to rise 10° per

ograph (see Chromatography ⟨621⟩) equipped with a flame- minute to 280°. The area of the C19H36O2 peak is not lessionization detector, helium being used as the carrier gas. than 99% of the total peak area.The following conditions have been found suitable: a 0.25- Refractive index ⟨831⟩: 1.452 at 20°.mm × 30-m capillary column coated with a 1-µm layer of Methyl Palmitate, C17H34O2—270.45 [112-39-0]—phase G2; the injection port temperature is maintained at White solid.280°; the detector temperature is maintained at 300°; the Assay—Inject an appropriate volume into a gas chromat-column temperature is maintained at 180° and pro- ograph (see Chromatography ⟨621⟩) equipped with a flame-grammed to rise 10° per minute to 280°. The area of the ionization detector, helium being used as the carrier gas.C13H26O2 peak is not less than 99.45% of the total peak The following conditions have been found suitable: a 0.25-area. mm × 30-m capillary column coated with a 1-µm layer ofMethyl Lignocerate, C25H50O2—382.66 [2442-49-1]— phase G2; the injection port temperature is maintained atWhite crystals. 300°; the detector temperature is maintained at 300°; theMethyl Linoleate, C19H34O2—294.47 [112-63-0]—Col- column temperature is maintained at 200° and pro-orless liquid. grammed to rise 10° per minute to 300°. The area of the

Assay—Inject an appropriate volume into a gas chromat- C17H34O2 peak is not less than 96.5% of the total peak area.ograph (see Chromatography ⟨621⟩) equipped with a flame- Methyl Red (2-[4-Dimethylaminophenylazo]benzoic Acid;ionization detector, helium being used as the carrier gas. C. I. Acid Red 2) C15H15N3O2, free acid— 269.30The following conditions have been found suitable: a 0.25- [493-52-7] C15H14N3O2Na, sodium salt—291.28mm × 30-m capillary column coated with a 1-µm layer of [845-10-3]—Use ACS reagent grade. The free acid is recom-phase G2; the injection port temperature is maintained at mended for nonaqueous titrations, particularly when an300°; the detector temperature is maintained at 300°; the aprotic solvent is used. The sodium salt is recommended forcolumn temperature is maintained at 200° and pro- titrations in aqueous media and also for nonaqueous titra-grammed to rise 10° per minute to 300°. The area of the tions where the medium is an amphiprotic solvent. The hy-C19H34O2 peak is not less than 99% of the total peak area. drochloride salt is recommended for titrations in aqueous

Methyl Linolenate, C19H32O2—292.46 [301-00-8]— media and amphiprotic solvents.Colorless liquid. Methyl Stearate, C19H38O2—298.50 [112-61-8]—Off-

Assay—Inject an appropriate volume into a gas chromat- white, crystalline solid.ograph (see Chromatography ⟨621⟩) equipped with a flame- Assay—Inject an appropriate specimen into a suitable gasionization detector, helium being used as the carrier gas. chromatograph (see Chromatography ⟨621⟩) equipped withThe following conditions have been found suitable: a 0.25- a flame-ionization detector, helium being used as the carriermm × 30-m capillary column coated with a 1-µm layer of gas. The following conditions have been found suitable: aphase 14% cyanopropylphenyl-86% dimethylpolysiloxane; capillary column coated with a 1-µm layer of phase G2; thethe injection port temperature is maintained at 280°; the injection port temperature is maintained at 300°; the detec-detector temperature is maintained at 300°; the column tor temperature is maintained at 300°; the column tempera-temperature is maintained at 180° and programmed to rise ture is maintained at 200° and programmed to rise 10° per10° per minute to 280°. The area of the C19H32O2 peak is minute to 300°. The area of the C19H38O2 peak is not lessnot less than 99% of the total peak area. than 99% of the total peak area.

Refractive index ⟨831⟩: between 1.469 and 1.473 at 20°. Melting range ⟨741⟩: between 40° and 42°.Methyl Methacrylate [80-62-6]—Use a suitable grade. Methyl Sulfoxide [67-68-5]—See Dimethyl Sulfoxide.Methyl Myristate, C15H30O2—242.40 [124-10-7]—Col- Methyl Yellow (p-Dimethylaminoazobenzene), C14H15N3—

orless liquid. 225.3 [60-11-7]—Use a suitable grade.


Methylamine, 40 Percent in Water, CH5N—31.06 Melting range ⟨741⟩: between 59° and 63°, but the[74-89-5]—Colorless liquid. range between beginning and end of melting does not ex-

ceed 2°.Assay—Using a syringe, transfer about 0.5 mL of a well-4-Methylpentan-2-ol, C6H14O—102.2—Use a suitableshaken specimen to 100 mL of water at a point below the

grade.surface of the water. Determine the weight of the specimen2-Methylpentane (2-Methyl-pentane; 1,1-Dimethylbutane;by weighing the syringe before and after the transfer. Mix,

Isohexane), C6H14—86.18 [107-83-5]—Use a suitableand titrate with 0.5 N hydrochloric acid VS, determining thegrade with a content of not less than 99.0%.endpoint potentiometrically, using a silver-silver chloride pH

4-Methyl-2-pentanone (Methyl Isobutyl Ketone),electrode and a calomel reference electrode. Perform a(CH3)2CHCH2COCH3—100.16 [108-10-1]—Use ACS rea-blank determination, and make any necessary correction.gent grade.Each mL of 0.5 N hydrochloric acid is equivalent to

2-Methyl-2-propyl-1,3-propanediol, C7H16O2—132.2015.53 mg of CH5N: between 39.0% and 41.0% is found.[78-26-2]—White crystals, melting at about 58°.Refractive index ⟨831⟩: between 1.3680 and 1.3710, at N-Methylpyrrolidine (1-Methylpyrrolidine), C4H8NCH3—20°. 85.15 [120-94-5]—Use a suitable grade.p-Methylaminophenol Sulfate, (p-CH3NHC6H4OH)2 · Mineral Acid—Use Hydrochloric Acid or Sulfuric Acid.H2SO4—344.38 [55-55-0]—Use ACS reagent grade. 5,800, 23,700, and 100,000 Molecular Weight (MW)4-Methylbenzophenone, C14H12O—196.25 Pullulan Standards (a commercial Pullulan Standard set[134-84-9]—Use a suitable grade. contains standards having several molecular weights:

Melting range ⟨741⟩: between 56.5° and 57°. 5,800; 12,000; 24,000; 48,000; 100,000; 186,000;Methylbenzothiazolone Hydrazone Hydrochloride, 380,000; and 750,000) [9057-02-7]—Use a suitable grade.

C8H10ClN3S · H2O—233.7 [38894-11-0] (monohydrate Each individual Pullulan Standard with a different molecularform)—215.70 (anhydrous form); [149022-15-1] (hydrate weight, such as 5,800, 24,000, or 100,000, is equivalentlyform)—An almost white or yellowish, crystalline powder. used.

Suitability for determination of aldehydes—To 2 mL of alde- [NOTE—The standard set is available from Polymer Labora-hyde-free methanol add 60 µL of a 1 g per L solution of tories (www.polymerlabs.com), Sigma-Aldrich (www.sigma-propionaldehyde in aldehyde-free methanol and 5 mL of a aldrich.com), and Waters (www.waters.com).]4 g per L solution of methylbenzothiazolone hydrazone hy- Molybdic Acid (85 Percent Molybdic Acid) [7782-91-4]—drochloride. Mix, and allow to stand for 30 minutes. Prepare Use ACS reagent grade.a blank, omitting the propionaldehyde solution. Add Monobasic Potassium Phosphate—See Potassium Phos-25.0 mL of a 2 g per L solution of ferric chloride to the test phate, Monobasic.solution and to the blank, dilute with acetone to 100.0 mL, Monobasic Sodium Phosphate—See Sodium Phosphate,and mix. The absorbance of the test solution, measured at Monobasic.660 nm using the blank as compensation liquid, is not less Monochloroacetic Acid (Chloroacetic Acid, Chloroethanoicthan 0.62. Acid), CH2ClCOOH—94.50 [79-11-8]—Use ACS reagent

Use a suitable grade with a content of not less than 97%. grade.(R)-(+)-alpha-Methylbenzyl Isocyanate ((R)-(+)- Monoethanolamine, (2-Aminoethanol) C2H7NO—61.08—

1-Phenylethyl Isocyanate), C9H9NO—147.17 Use ACS reagent grade.[33375-06-3]—Use a suitable grade with a content of NLT Morin (Morin Hydrate; 2′,3,4′,5,7-Pentahydroxyflavone99.0%. Monohydrate), C15H10O7 · H2O—320.25 [480-16-0]—Use a

(S)-(−)-α-Methylbenzyl Isocyanate C9H9NO—147.18 suitable grade.[14649-03-7]—Use a suitable grade. Morpholine (Tetrahydro-1,4-oxazine), C4H9NO—87.12

Methylene Blue, C16H18ClN3S · 3H2O—373.90 [110-91-8]—Use ACS reagent grade.[7220-79-3]—Dark green crystals or a crystalline powder, Naphthalene, C10H8—128.17 [91-20-3]—Monoclinichaving a bronzelike luster. One g dissolves in about 25 mL prismatic plates, or white scales or powder. Use a suitableof water and in about 65 mL of alcohol. Soluble in chloro- grade with a content of not less than 98%.form. Use a suitable grade with a dye content of not less 1,3-Naphthalenediol (Naphthoresorcinol), C10H6(OH)2—than 85%. 160.17 [132-86-5]—Grayish-white to tan crystals or pow-

Methylene Chloride (Dichloromethane), CH2Cl2—84.93 der. Freely soluble in methanol; sparingly soluble in water,[75-09-2]—Use ACS reagent grade Dichloromethane. in alcohol, and in ether.

5,5′-Methylenedisalicylic Acid (3,3′-Methylene-bis[6-hy- Melting range ⟨741⟩: between 122° and 127°.droxybenzoic Acid]), C15H12O6—288.25 [122-25-8]—Use a Solubility in methanol—Dissolve 500 mg in 50 mL ofsuitable grade. methanol: the solution is clear and complete.3-O-Methylestrone, C19H24O2—284.39—Use a suitable 2,7-Naphthalenediol (2,7-Dihydroxynaphthalene),grade. C10H8O2—160.17 [582-17-2]—Off-white to yellow, crys-[NOTE—Commercially available as catalog number 1883-5 talline solid or powder. Dissolves in acetone.from Research Plus, Inc., P.O. Box 324, Bayonne, NJ 07002,

Melting range ⟨741⟩: between 187° and 191°.fax number 908-754-2901, Web site: www.researchplus.2-Naphthalenesulfonic Acid, C10H8O3S · H2O—226.25com.]

[120-18-3]—Off-white to light gray crystals. Soluble in2-Methyl-5-nitroimidazole, C4H4N3O2—127.10water.[88052-22-2]—Use a suitable grade.

[NOTE—Available as Catalog No. 13,625-5 from Sigma-Al- Assay—Dissolve about 1 g, accurately weighed, indrich, www.sigma-aldrich.com.] 100 mL of water, add phenolphthalein TS, and titrate with

N-Methyl-N-nitroso-p-toluenesulfonamide (p-Tolyl- 0.1 N sodium hydroxide VS. Perform a blank determination,sulfonylmethylnitrosamide), C8H10N2O3S—214.24—Light yel- and make any necessary correction. Each mL of 0.1 N so-low crystals or powder. Insoluble in water; soluble in ben- dium hydroxide is equivalent to 22.63 mg of C10H8O3S ·zene, in carbon tetrachloride, and in chloroform. H2O. Not less than 98.0% is found.

Melting range ⟨741⟩: between 122° and 126°, but therange between beginning and end of melting does not ex-ceed 2°.


1-Naphthol (Alphanaphthol), C10H7OH—144.17 72240, available from Fluka Chemical Corp., fax[90-15-3]—Colorless or slightly pinkish crystals or crystalline 1-800-962-9591, Web site: www.sigma-aldrich.com.]powder. Nickel Sulfate, NiSO4 · 6H2O—262.85 [7786-81-4]—

2-Naphthol (Betanaphthol), C10H7OH—144.17 Use ACS reagent grade.[135-19-3]—White leaflets or crystalline powder. Discolors Nickel (II) Sulfate Heptahydrate, NiSO4 · 7H2O—280.9on exposure to light. Very slightly soluble in water; soluble [10101-98-1]—Use a suitable grade.in alcohol, in ether, in chloroform, and in solutions of alkali β-Nicotinamide Adenine Dinucleotide, C21H27N7O14P2—hydroxides. 663.4 [53-84-9]—White, very hygroscopic powder. Freely

soluble in water.Melting range ⟨741⟩: between 121° and 123°.Assay—Dissolve 17.9 g of anhydrous dibasic sodiumSolubility in alcohol—A solution of 1 g in 10 mL of alcohol

phosphate in water to make 500 mL (Solution A). Dissolveis complete and colorless or practically so.6.8 g of monobasic potassium phosphate in water to makeResidue on ignition (Reagent test): not more than 500 mL (Solution B). To a volume of Solution A, add Solution0.05%. B until the mixture is adjusted to a pH of 7.0 (about 2:1 by

Acidity—Shake 1 g with 50 mL of water occasionally dur- volume of Solutions A and B) to obtain a pH 7.0 Buffer.ing 15 minutes, and filter: the filtrate is neutral to litmus. Transfer about 25 mg of β-nicotinamide adenine dinucleo-

1-Naphthol—Boil 100 mg with 10 mL of water until dis- tide, accurately weighed, to a 25-mL volumetric flask, dis-solved, cool, and filter. Add to the filtrate 0.3 mL of 1 N solve in and dilute with water to volume, and mix. Transfersodium hydroxide and 0.3 mL of 0.1 N iodine: no violet 0.2 mL of this solution to a 10-mL volumetric flask, dilutecolor is produced. with pH 7.0 Buffer to volume, and mix. Use this solution as

the Assay preparation. Determine the absorbances of the As-Insoluble in ammonia (naphthalene, etc.)—Shake 500 mgsay preparation and the pH 7.0 Buffer in 1-cm cells at awith 30 mL of ammonia TS: the 2-naphthol dissolves com-wavelength of 260 nm, using water as the reference. Calcu-pletely and the solution is not darker than pale yellow.late the quantity, in mg, of C21H27N7O14P2 in the portion ofNaphthol Dipotassium Disulfonate (2-Naphthol-6,8-di-β-nicotinamide adenine dinucleotide taken by the formula:potassium Disulfonate), C10H6K2O7S2—380.48

[842-18-2]—Use a suitable grade.(0.6634/17.6)(10/0.2)(25)(AA – AB)[NOTE—A suitable grade is available as “2-naphthyl-6,8-

disulfonic acid dipotassium salt” from Pfaltz and Bauer, Inc.,in which AA and AB are the absorbances of the Assay prepa-www.pfaltzandbauer.com.]ration and the pH 7.0 Buffer, respectively. Not less thanNaphthol Disodium Disulfonate (2-Naphthol-3,6-diso-94.5% is found.dium Disulfonate), C10H6Na2O7S2—348.26—Use a suitable

Nicotinamide Adenine Dinucleotide Phosphate-grade.adenosine-5′-triphosphate Mixture—Use a suitable grade.p-Naphtholbenzein, C27H18O2—374.43 [145-50-6]—

Red-brown powder. Use a suitable grade. Suitability—When used in the assay of lactulose, deter-β-Naphthoquinone-4-sodium Sulfonate, C10H5NaO5S— mine that a suitable absorbance-versus-concentration slope

260.20—Yellow to orange-yellow crystals or crystalline pow- is obtained, using USP Lactulose RS , the reagent blank ab-der. Soluble in about 10 parts of water; insoluble in alcohol. sorbance being not more than 0.020. The commercially

available reagent contains 64 mg of nicotinamide adenineLoss on drying ⟨731⟩—Dry it in vacuum at about 50°: itdinucleotide phosphate and 160 mg of adenosine-5′-loses not more than 2.0% of its weight.triphosphate per vial. The mixture is buffered and stabilized.Residue on ignition (Reagent test)—Ignite 1 g of dried For use in the Assay of lactulose it is diluted with water tosample with 3 mL of sulfuric acid: the residue weighs be- 100 mL.tween 265 and 280 mg (between 26.5% and 28.0%). Nicotinic Acid—Use Niacin (USP monograph).Naphthoresorcinol (1,3-Dihydroresorcinol), C10H8O2— Ninhydrin, C9H4O3 · H2O—178.14 [485-47-2]—Use160.17 [132-86-5]—Use a suitable grade. ACS reagent grade.2-Naphthyl Chloroformate (Chloroformic Acid 2-Naphthyl Nitric Acid, HNO3—63.01 [7697-37-2]—Use ACS rea-Ester), ClCOOC10H7—206.62 [7693-50-7]—Use a suitable gent grade.grade. Nitric Acid, Diluted (10 percent HNO3) [7697-37-2]—Di-[NOTE—A suitable grade is available from TCI America, lute 143 mL of nitric acid with water to 1000 mL.www.tciamerica.com.] Nitric Acid, Fuming (90 Percent Nitric Acid), HNO3—1-Naphthylamine, C10H9N—143.19 [134-32-7]—Use 63.01 [7697-37-2]—Use ACS reagent grade Nitric Acid,a suitable grade. 90 Percent.1-Naphthylamine Hydrochloride, C10H7NH2 · HCl— Nitric Acid, Lead-Free—Use ACS reagent grade.179.65 [552-46-5]—White, crystalline powder that turns

Lead—To 100 g add 0.1 g of anhydrous sodium carbon-bluish upon exposure to light and air. Soluble in water, inate and evaporate to dryness. Dissolve the residue in water,alcohol, and in ether.heating slightly, and dilute with the same solvent toA 1 in 100 solution, make slightly acid with acetic acid,50.0 mL. Determine the lead content by atomic absorptiongives a violet color with 5 drops of ferric chloride TS. A 1 inspectrophotometry (see Spectrophotometry and Light-Scatter-40 solution in diluted acetic acid is colorless and not moreing ⟨851⟩) measuring the absorbance at 283.3 nm orthan slightly opalescent.217.0 nm using a lead hollow-cathode lamp and anResidue on ignition (Reagent test)—Ignite 200 mg with a air–acetylene flame. It contains not more than 0.1 ppm offew drops of sulfuric acid: the weight of the residue is negli- lead (Pb).gible. Nitric Oxide–Nitrogen Dioxide Detector Tube—A fuse-N-(1-Naphthyl)ethylenediamine Dihydrochloride, sealed glass tube so designed that gas may be passedC10H7NH(CH2)2NH2 · 2HCl—259.17 [1465-25-4]—Use through it and containing suitable absorbing filters and sup-ACS reagent grade. port media for an oxidizing layer and the indicator diphenylNeutralized Alcohol—See Alcohol, Neutralized. benzidine.Nickel, Ni—58.6934 [7440-02-0]—Use a suitable

Measuring range: 0.5 to 10 ppm.grade.[NOTE—Available from Draeger Safety, Inc., www.draeger.Nickel-Aluminum Catalyst—Use a suitable grade.

com, or from Gastec Corp., www.gastec.co.jp, distributed in[NOTE—A suitable grade is “Raney Nickel, Active Catalyst,”the USA by www.nextteq.com.]available as “aluminum–nickel alloy,” catalog number


Nitrilotriacetic Acid, N(CH2COOH)3—191.14 sulfate, and dilute with water to 100 mL: the solution is[139-13-9]—Use ACS reagent grade. deep red in color and exhibits an absorption maximum at

4′-Nitroacetophenone (p′-Nitroacetophenone), 510 nm. To 1.0 mL of the solution add 1.0 mL of 0.01 MC8H7NO3—165.15 [100-19-6]—Yellow crystals. ceric sulfate: the red color is discharged.

Nitroso R Salt (1-Nitroso-2-naphthol-3,6-disodiumAssay—Inject an appropriate ether solution of the speci-Disulfonate), NOC10H4OH(SO3Na)2—377.26 [525-05-3]—men (about 0.5 µL) into a suitable gas chromatograph (seeYellow crystals or crystalline powder. One g dissolves inChromatography ⟨621⟩) equipped with a thermal conductiv-about 40 mL of water; insoluble in alcohol.ity detector, helium being used as the carrier gas. The fol-

lowing conditions have been found suitable: a 4-mm × Sensitiveness—Dissolve 500 mg of sodium acetate in a so-1.8-m stainless steel column containing 10% phase G1 on lution of 0.4 mg of cobaltous chloride (0.1 mg of cobalt) insupport S1A; the injection port and detector temperatures 5 mL of water. Add 1 mL of diluted acetic acid, and followare maintained at 200° and 300°, respectively; the column with 1 mL of a solution of the nitroso R salt (1 in 500): atemperature is maintained at 170° and programmed to rise red color, which is produced at once, persists when the so-3° per minute to 220°. The area of the 4′-nitroacetophe- lution is boiled with 1 mL of hydrochloric acid for 1 minute.none peak is not less than 97% of the total peak area. 1-Nitroso-2-naphthol, C10H7NO2—173.17

[131-91-9]—Brown to yellowish-brown powder. Insoluble inMelting range ⟨741⟩: between 78° and 80°.water; soluble in alcohol, in benzene, in ether, in carbono-Nitroaniline, NO2C6H4NH2—138.12 [88-74-4]—Or-tetrachloride, and in acetic acid.ange-yellow crystals. Slightly soluble in cold water; soluble

in hot water; freely soluble in alcohol and in chloroform. It Assay—Transfer about 250 mg, previously dried over silicaforms water-soluble salts with mineral acids. gel to constant weight and accurately weighed, to a glass-

stoppered flask, and dissolve in 10 mL of sodium hydroxideMelting range ⟨741⟩: between 71° and 72°.solution (1 in 10). Cool the solution in an ice bath, addp-Nitroaniline, NO2C6H4NH2—138.12 [100-01-6]—dilute sulfuric acid (1 in 6) until a slight, permanent precipi-Bright yellow, crystalline powder. Insoluble in water; solubletate is formed and the solution is slightly acid, then add 3 gin alcohol and in ether.of potassium iodide, shake to dissolve, add 20 mL of diluteMelting range ⟨741⟩: between 146° and 148°. sulfuric acid (1 in 6), immediately insert the stopper in the

Solubility—Separate 1-g portions dissolve in 30 mL of al- flask, and allow to stand in the dark for 2 hours. Titrate thecohol and in 40 mL of ether, respectively, to yield solutions liberated iodine with 0.1 N sodium thiosulfate VS, addingthat are clear or practically so. 3 mL of starch TS as the endpoint is approached. Perform a

Residue on ignition (Reagent test): not more than 0.2%. complete blank determination, and make any necessary cor-Nitrobenzene, C6H5NO2—123.11 [98-95-3]—Use ACS rection. Each mL of 0.1 N sodium thiosulfate is equivalent

reagent grade. to 8.66 mg of C10H7NO2: not less than 95.0% is found.p-Nitrobenzenediazonium Tetrafluoroborate, Melting range ⟨741⟩: between 109° and 111°.

NO2C6H4N2BF4—236.92 [456-27-9]—Yellow-gold crystals. Residue on ignition (Reagent test): not more than 0.2%.Soluble in acetonitrile. [CAUTION—Shock-sensitive; keep Nitrous Oxide Certified Standard [10024-97-2]—A con-refrigerated.] tainer of 99.9% nitrous oxide. It is available from most sup-Assay—Transfer about 30 mg, accurately weighed, to a pliers of specialty gases.

low-actinic, 100-mL volumetric flask. Dissolve in 0.01 N hy- Nonadecane, C19H40—268.52 [629-92-5]—White solid.drochloric acid, dilute with 0.01 N hydrochloric acid to vol- Assay—Inject an appropriate specimen into a suitable gasume, and mix. Using low-actinic glassware, dilute 2.0 mL of chromatograph (see Chromatography ⟨621⟩) equipped withthe resulting solution with spectrophotometric grade metha- a thermal conductivity detector, helium being used as thenol to 50.0 mL. Measure the absorbance of this solution in a carrier gas. The following conditions have been found suita-1-cm cell at about 255 nm, using methanol as the blank. ble: 3-mm × 1.8-m stainless steel column containing 5%Calculate the absorptivity of the solution by dividing the phase G2 on support S1AB; the injection port temperaturemeasured absorbance by the concentration in g per mL. is maintained at 330°; the detector temperature is main-Calculate the assay value by the formula: tained at 300°; and the oven temperature is held initially at

190° and allowed to rise gradually to 250°. The area of the100a/59.4nonadecane peak is not less than 99% of the total peakarea.in which a is the absorptivity of the solution: not less than

Melting range ⟨741⟩: between 31.5° and 33.5°.95.0% is found.Nonanoic Acid, C9H18O2—158.24 [112-05-0]—Clear,p-Nitrobenzyl Bromide, NO2C6H4CH2Br—216.03—Al-

colorless to faint yellow liquid. Miscible with water and withmost white to pale yellow crystals, darkening on exposuremethanol.to light. Practically insoluble in water; freely soluble in alco-

hol, in ether, and in glacial acetic acid. Store in tight, light- Assay—Accurately weigh about 500 mg, transfer to aresistant containers. suitable container, add 30 mL of water, and mix. Add 40 mL

of water, and mix. Add phenolphthalein TS, and titrate withMelting range ⟨741⟩: between 98° and 100°.0.1 N sodium hydroxide VS. Each mL of 0.1 N sodium hy-Solubility—Separate 200-mg portions yield clear solutionsdroxide is equivalent to 15.82 mg of C9H18O2: not less thanin 5 mL of alcohol and in 5 mL of glacial acetic acid.96.0% of C9H18O2 is found.Residue on ignition (Reagent test): negligible, from

Refractive index ⟨831⟩: about 1.432 at 20°.200 mg.Nonionic Wetting Agent—Use a suitable amphoteric4-(p-Nitrobenzyl)pyridine, C12H10N2O2—214.22

surfactant.[1083-48-3]—Yellow crystals. Soluble in acetone. Use a suit-[NOTE—A suitable grade is commercially available as Tritonable grade with a content of not less than 98%.

X-100 or Octoxynol 9.]Nitromethane, CH3NO2—61.04 [75-52-5]—Use ACSNonoxynol-9 (Igepal CO-630, Semicid, Staycept, Tergitolreagent grade.

TP-9, Sterox), (C2H4O)nC15H24O— [26027-38-3]—Use a suita-5-Nitro-1,10-phenanthroline, C12H7N3O2—225.20ble grade.[4199-88-6]—White powder. Soluble in water.

1-Nonyl Alcohol (1-Nonanol), CH3(CH2)8OH—144.25Melting range ⟨741⟩: between 198° and 200°. [143-08-8]—Colorless liquid.Suitability as redox indicator—Dissolve 25 mg in a mini-

mum volume of diluted sulfuric acid, add 10 mg of ferrous


Assay—Not less than 97% of C9H20O is found, a suitable [NOTE—Available from Draeger Safety, Inc., www.draeger.gas chromatograph equipped with a flame-ionization detec- com.]tor and helium being used as the carrier gas at a flow rate Oligo-deoxythymidine—Polymeric length: 18. Use a suit-of about 40 mL per minute. The following conditions have able grade.been found suitable: a 3.2-mm × 1.83-m stainless steel col- [NOTE—A suitable grade is available from BD Biosciences,umn packed with 20% phase G16 on support S1A; the in- www.bdbiosciences.com.]jection port, column, and detector temperatures are main- Orange G (the sodium salt of azobenzene-betanaphtholtained at about 250°, 160°, and 310°, respectively. disulfonic acid), C6H5N:NC10H4(OH)(SO3Na)2-2,6,8—452.37

[1936-15-8]—Orange to brick-red powder or dark red crys-Refractive index ⟨831⟩: between 1.432 and 1.434 attals. Readily soluble in water, yielding an orange-yellow so-20°.lution; slightly soluble in alcohol; insoluble in ether and inn-Nonylamine (1-Aminononane), C9H21N—143.27chloroform. The addition of tannic acid TS to its 1 in 500[112-20-9]—Use a suitable grade.solution causes no precipitation (acid color). The addition ofNonylphenol Polyoxyethylene Ether, (CH3)3CCH2Chydrochloric acid to a mixture of 500 mg of zinc dust and(CH3)2CH2C6H4O(CH2CH2O)XH, where x is approximately 4010 mL of its 1 in 500 solution produces decolorization.to 1900–2100 [9016-45-9]—White solid; melts at approxi-When filtered, the colorless filtrate, on standing exposed tomately 44°. Use a suitable grade.air, does not regain its original color (presence of azo-group).Nonylphenoxypoly(ethyleneoxy)ethanol—Clear, viscous,When heated, orange G does not deflagrate (distinctionpale yellow liquid. May exhibit slight solidification on cool-from nitro colors). The addition of barium or calcium chlo-ing; warming with agitation will restore to original condi-ride TS to a concentrated solution of orange G produces ation. Density: about 1.06. Soluble in alcohol, in xylene, andcolored, crystalline precipitate. The addition of hydrochloricin water. Suitable for use in gas–liquid chromatography.acid to its 1 in 500 solution produces no change; the addi-[NOTE—A suitable grade is “Igepal CO 710,” availabletion of sodium hydroxide TS to a similar solution produces afrom General Aniline and Film Corp., 140 West 51st St.,yellowish red to a Bordeaux color but no precipitation. Or-New York, NY 10020.]ange G dissolves in sulfuric acid with an orange to yellow-Normal Butyl Alcohol—See Butyl Alcohol.ish-red color. No change in color results upon diluting theNormal Butyl Nitrite—See n-Butyl Nitrite.solution cautiously with water.Normal Butylamine—See n-Butylamine.

Orcinol (5-Methylresorcinol), C7H8O2 · H2O—142.15n-Octadecane, CH3(CH2)16CH3—254.49 [593-45-3]—[6153-39-5]—White to light tan crystals.Use a gas chromatographic standard with a content of not

less than 99.5%. Assay—Transfer about 60 mg, accurately weighed, to aOctadecyl Silane [18623-11-5]—This reagent is formed in 100-mL volumetric flask, dissolve in methanol, dilute with

situ by reaction of the column support with a suitable silylat- methanol to volume, and mix. Transfer 5.0 mL of this solu-ing agent such as octadecyl trichlorosilane. tion to a 50-mL volumetric flask and dilute with methanol

Octanesulfonic Acid Sodium Salt (Sodium 1-octanesulfon- to volume, and mix. Using a suitable spectrophotometer,ate), C8H17NaO3S—216.27 [5324-84-5]—Use a suitable 1-cm cells, and methanol as the blank, record the absorb-grade with a content of not less than 99.0%. ance of the solution at the wavelength of maximum absorb-

1-Octanol (Alcohol C8; Capryl Alcohol; Octyl Alcohol), ance at about 273 nm. From the observed absorbance, cal-C8H18O—130.23 [111-87-5]—Use ACS reagent grade. culate the absorptivity (see Spectrophotometry and Light-

Octanophenone, C14H20O—204.31 [1674-37-9]—Col- scattering ⟨851⟩): the absorptivity is not less than 13.2, cor-orless liquid. responding to not less than 98% of C7H8O2 · H2O.

Assay— Melting range ⟨741⟩: between 58° and 61°.Orthophenanthroline—See 1,10-Phenanthroline.MOBILE PHASE—Prepare a filtered and degassed mixture ofOsmium Tetroxide (Osmic Acid; Perosmic Anhydride),acetonitrile and water (7:3).

OsO4—254.23 [20816-12-0]—Use ACS reagent grade.PROCEDURE—Inject about 20 µL into a suitable liquid chro- Oxalic Acid, H2C2O4 · 2H2O—126.07 [6153-56-6]—Usematograph (see Chromatography ⟨621⟩) equipped with a ACS reagent grade.254-nm detector and a 4.6-mm × 15.0-cm column that 3,3′-Oxydipropionitrile, O(CH2CH2CN)2—124.14contains packing L1. The flow rate is about 2 mL per min- [1656-48-0]—Clear, colorless to slightly yellow liquid. Re-ute. The area of the C14H20O peak is not less than 99% of fractive index: about 1.446 at 20°.the total peak area.Boiling range: between 174° and 176° at 10 mm ofRefractive index ⟨831⟩: 1.5043 at 20°. mercury.Octoxynol 9—See Nonionic Wetting Agent. Oxygen-Helium Certified Standard—A mixture of 1.0%(p-tert-Octylphenoxy) nonaethoxyethanol, C34H62O11— oxygen in industrial grade helium. It is available from most646.85—Use a suitable grade. suppliers of specialty gases.[NOTE—A suitable grade is available commercially as Packings for High-Pressure Liquid Chromatography—“Tergitol Nonionic NPX,” and as “Triton N101,” from rea- See packings for high-pressure liquid chromatography in thegent suppliers.] Chromatographic Reagents section under Chromatography(p-tert-Octylphenoxy)polyethoxyethanol—Use a suitable ⟨621⟩.grade. Palladium Catalyst—Use a suitable grade.[NOTE—A suitable grade is available commercially as “Tri- [NOTE—A suitable grade is available commercially as “Pal-ton 100” from reagent suppliers.] ladium Catalyst, Type I (5% Palladium on Calcium Carbon-Octyl Sulfate, Sodium Salt, C8H17O4SNa—232.27—White ate),” from Engelhard Industries, Inc., fax number (864)powder. 885-1375.]

Solubility—A 2-g portion dissolves in 100 mL of water. Palladium Chloride, PdCl2—177.33 [7647-10-1]—Melting range ⟨741⟩: between 195° and 197°, with Brown, crystalline powder. Soluble in water, in alcohol, in

decomposition. acetone, and in diluted hydrochloric acid.Odorless Absorbent Paper—See Filter Paper, Quantitative. Assay—Dissolve 80 mg, accurately weighed, in 10 mL ofOlefin Detector Tube—A fuse-sealed glass tube so de- diluted hydrochloric acid, dilute with water to 50 mL, and

signed that gas may be passed through it and containing add 25 mL of a 1 in 100 solution of dimethylglyoxime insuitable absorbing filters and support media for the indica- alcohol. Allow to stand for 1 hour, and filter. Check for com-tor in a stabilized form of permanganate. plete precipitation with the dimethylglyoxime solution. Ig-

Measuring range: 0.06 to 3.2 Vol.–% Propylene, 0.04 to nite the precipitate in a tared platinum crucible at 850° for2.4 Vol.–% Butylene. 2 hours, cool, and weigh the palladium. The weight of the


residue is not less than 59.0% of the weight of the test Add 5 mL of hydrochloric acid and 50 mL of water, and stirspecimen. until dissolved. Cool to about 15°, add about 25 g of

Palladous Chloride—See Palladium Chloride. crushed ice, and slowly titrate with 0.1 M sodium nitrite VSPancreatic Digest of Casein (a bacteriological peptone; until a glass rod dipped into the titrated solution produces

Tryptone)—A grayish-yellow powder, having a characteristic, an immediate blue ring when touched to starch iodide pa-but not putrescent, odor. Freely soluble in water; insoluble per. When the titration is complete, the endpoint is repro-in alcohol and in ether. ducible after the mixture has been allowed to stand for

1 minute. Each mL of 0.1 M sodium nitrite is equivalent toNitrogen content (Reagent test)—Determine by the13.71 mg of C7H7NO2. Not less than 98.5% is found.Kjeldahl method: 9.0%–14.0% is found.

Melting range ⟨741⟩: between 186° and 189°.Loss on drying ⟨731⟩—Dry it at 100° to constant weight:it loses not more than 7.0% of its weight. Loss on drying ⟨731⟩—Dry it at 105° for 2 hours: it loses

not more than 0.2% of its weight.Residue on ignition ⟨281⟩—Ignite 500 mg with 1 mL ofsulfuric acid: the residue weighs not more than 75 mg Residue on ignition (Reagent test): not more than 0.1%.(15%). Paraformaldehyde, (CH2O)n [30525-89-4]—Fine, white

powder.Microbial content—NMT 10,000 cfu/g.Assay—Transfer about 1 g, accurately weighed, to aBacteriological test—Prepare medium of the following

250-mL conical flask containing 50.0 mL of 1 N sodium hy-composition:droxide VS, and mix by swirling. Immediately, and slowly,2% of digest, 0.5% of sodium chloride, and 1.5% of agaradd 50 mL of hydrogen peroxide TS, previously neutralizedin purified water.to bromothymol blue, through a small funnel placed in theAdjust with diluted hydrochloric acid or diluted sodiumneck of the flask. After the reaction moderates, rinse thehydroxide to a pH of 7.2–7.4. Autoclave at 121° for 15 min.funnel and inner wall of the flask with water, allow the solu-Growth-supporting properties—Slants of the above me- tion to stand for 30 minutes, add bromothymol blue TS,dium, inoculated with Escherichia coli ATCC 25922, Enter- and titrate the excess alkali with 1 N sulfuric acid VS. Eachobacter aerogenes ATCC 13048, Salmonella enterica ATCC mL of 1 N sodium hydroxide is equivalent to 30.03 mg of14028, Pseudomonas aeruginosa ATCC 27853, Staphylococ- HCHO: not less than 95% is found.cus aureus ATCC 25923, and Staphylococcus epidermidis

Residue on ignition: not more than 0.1%.ATCC 12228, show characteristic growth after incubationfor 24 h. Solubility in ammonia—Dissolve 5 g in 50 mL of ammonia

The above medium, to which 5% of sheep blood or TS: a practically clear, colorless solution results.rabbit blood has been added, and which has been inocu- Reaction—Shake 1 g with 20 mL of water for aboutlated and poured into Petri dishes, shows characteristic al- 1 minute, and filter: the filtrate is neutral to litmus.pha or beta zones around colonies of Streptococcus Pectate Lyase [9015-75-2]—An enzyme obtained frompneumoniae ATCC 6305 and Streptococcus pyogenes ATCC Aspergillus sp. Light brown, viscous liquid. Specific gravity is49117, recognizable within 24 h and fully developed after about 1.5. It is readily soluble in water. It is supplied at48 h of incubation. approximately 14 units per mL (at pH 8.0 in Tris-HCl buffer

The above medium, to which 10% of sheep blood or [50 mM of Tris(hydroxymethyl)aminomethane containingrabbit blood has been added, and which then has been 1 mM of CaCl2, pH 8.0] in a solution of 50% glycerol andheated to 80°–90° until the blood has turned chocolate- 0.02% sodium azide. One unit is defined as the enzymebrown, permits the growth of Neisseria gonorrhoeae ATCC activity that produces 1 µmol of unsaturated product per19424 colonies within 48 h when incubated in an atmos- minute.phere containing 10% of carbon dioxide. Activity—Pancreatin [8049-47-6]—Use a grade of pancreatin which

PECTIN SOLUTION—Transfer a quantity of Pectin, equivalentmeets the USP requirements for amylase, lipase, and prote-to 0.05 g on the dried basis, to a 100-mL volumetric flask.ase activities specified for the official substance.[NOTE—Pectin has a molecular weight of 103,000 Da; its de-Papaic Digest of Soybean Meal—A soluble nutrient ma-gree of esterification (percentage of galacturonic acidterial prepared by the action of the enzyme papain on soy-groups substituted with methyl) is 12.] Moisten with 0.1 mLbean meal followed by suitable purification and concentra-of 2-propanol. Add 50 mL of water to the flask, and mix thetion. It contains fermentable carbohydrates.solution with a magnetic stirrer. Use 0.5 N sodium hydrox-Loss on drying ⟨731⟩—Dry it at 100° to constant weight: ide to adjust the solution to a pH of 12. Stop the stirrer,it loses not more than 7.0% of its weight. and allow the solution to stand undisturbed at room tem-

Residue on ignition (Reagent test)—Ignite 500 mg with perature for 15 minutes. Adjust the solution with 0.5 N hy-1 mL of sulfuric acid: the residue weighs not more than drochloric acid to a pH of 8.0. Dilute with water to volume.75 mg (15.0%). TRIS BUFFER SOLUTION—Transfer 6.055 g of Tris(hydroxy-

Coagulable protein—Heat a filtered solution (1 in 20) to methyl)aminomethane and 0.147 g of calcium chlorideboiling: no precipitate forms. (CaCl2 · H2O) to a 1000-mL volumetric flask containing

Microbial content—NMT 104 cfu/g 950 mL of water, and mix. Adjust the solution with 1 N hy-drochloric acid to a pH of 8.0. Dilute with water to volume.Nitrogen content (Reagent test)—Determine by the

Kjeldahl method, using a test specimen previously dried at DILUTED PECTATE LYASE—Transfer 0.5 mL of Pectate Lyase to105° to constant weight: not less than 8.5% is found. a 50-mL volumetric flask, dilute with Tris buffer solution to

Paper, Odorless Absorbent—See Filter Paper, Quantita- volume, and mix.tive. PROCEDURE—Add the solutions set forth in the table below

Para-aminobenzoic Acid (p-Aminobenzoic Acid), to quartz cuvettes.H2NC6H4COOH—137.14 [150-13-0]—White or slightlyyellow crystals or crystalline powder, becoming discolored

Tris Dilutedon exposure to air or light. One g dissolves in 170 mL ofbuffer Pectin pectatewater, in 9 mL of boiling water, in 8 mL of alcohol, and in

solution solution lyase Water50 mL of ether. Freely soluble in solutions of alkali hydrox-Label (mL) (mL) (mL) (mL)ides and carbonates; soluble in warm glycerin; sparingly sol-

Enzyme blank 0.5 1.0 0 1.0uble in diluted hydrochloric acid; slightly soluble in chloro-Test blank 0.5 0 0.5 1.5form. Store in tight, light-resistant containers.Test solution 0.5 1.0 0.5 0.5Assay—Accurately weigh about 300 mg, previously dried

at 105° for 2 hours, and transfer to a beaker or casserole.


Perform the test on the solutions so obtained, using a suita- 2.0% HEMOGLOBIN SOLUTION—Dissolve and dilute 2.5 g ofble UV-Vis spectrophotometer (see Spectrophotometry and bovine hemoglobin with water to 100 mL. Dilute 80 mL ofLight-Scattering ⟨851⟩) and using water as the blank. Mix the this solution with 0.3 M hydrochloric acid to a volume ofsolutions well at time 0, and immediately measure the ab- 100 mL.sorbances at 235 nm. Record the value for the Enzyme TRICHLOROACETIC ACID SOLUTION—Dilute 5 g of trichloroace-blank, A0−EB ; for the Test blank, A0−TB ; and for the Test solu- tic acid with water to 100 mL.tion, A0−TS . After incubation at room temperature for TEST SOLUTION—Transfer 5.0 mL of 2.0% Hemoglobin solu-30 minutes, determine the absorbance again at 235 nm for tion to a suitable container equilibrated at 37°. Add 1.0 mLthe Enzyme blank, A30−EB ; for the Test blank, A30−TB ; and for of Pepsin solution, mix by swirling, and incubate at 37° forthe Test solution, A30−TS . One unit is defined as the enzy- 10 minutes. Immediately add 10.0 mL of Trichloroacetic acidmatic activity that produces 1 µmol of unsaturated product solution, mix by swirling, and incubate at 37° for 5 minutes.from pectin per minute. Calculate the Pectate Lyase activity, Pass through a filter having a 0.8-µm or finer porosity.in units per mL, using the following formula:

CONTROL SOLUTION—Transfer 5.0 mL of 2.0% Hemoglobinsolution to a suitable container equilibrated at 37°. Mix by50(103)[(A30−TS − A30−EB − A30−TB) − (A0−TS − A0−EB − A0−TB)]/swirling, and incubate at 37° for 10 minutes. Immediately30ε235Ladd 10.0 mL of Trichloroacetic acid solution and 1.0 mL ofPepsin solution, mix by swirling, and incubate at 37° forin which 50 is the volume, in mL, of Diluted pectate lyase;5 minutes. Pass through a filter having a 0.8-µm or finer103 is the unit conversion factor; 30 is the time, in minutes,porosity.of the reaction; ε235 is the molar extinction coefficient, in

M−1cm−1, of the reaction product (4600 M−1 cm−1); and L is PROCEDURE—Determine the absorbances of the Test solu-the path length, in cm, of the reaction cuvette (1 cm). Alter- tion and Control solution, in 1-cm cells, at a wavelength ofnatively, these solutions, after being mixed in the cuvettes, about 280 nm, using water as the reference. Calculate thecan be immediately measured at 235 nm continuously in a activity of the portion of Purified Pepsin taken by therecording UV-Vis spectrophotometer set up for kinetic as- formula:says. The result is obtained by correcting the blank determi-

10,000(AU− AC)nation, using the Enzyme blank and the Test blank.Penicillinase—See Beta-lactamase.

in which AU and AC are the absorbances of the Test solutionPentadecane, C15H32—212.41 [629-62-9]—Colorlessand the Control solution, respectively.liquid.

Peptic Digest of Animal Tissue (a bacteriological pep-Assay—Inject an appropriate specimen into a gas chro-tone)—Tan powder, having a characteristic, but not putres-matograph (see Chromatography ⟨621⟩) equipped with acent, odor. Soluble in water; insoluble in alcohol and inflame-ionization detector, helium being used as the carrierether. An autoclaved solution (2 in 100) is clear and is neu-gas. The following conditions have been found suitable: atral or nearly so in its reaction.0.25-mm × 30-m capillary column coated with a 1-µm layer

Nitrogen content—Determine by the Kjeldahl method, us-of phase G2; the injection port temperature is maintained ating a test specimen previously dried at 105° to constant280°; the detector temperature is maintained at 300°; andweight: between 9.0% and 14.0% of nitrogen is found.the column temperature is maintained at 180° and pro-

grammed to rise 10° per minute to 280°. The area of the Residue on ignition ⟨281⟩—Ignite 500 mg with 1 mL ofC15H32 peak is not less than 99% of the total peak area. sulfuric acid: the residue weighs not more than 75 mg

(15%).Refractive index ⟨831⟩: between 1.430 and 1.434 at20°. Loss on drying ⟨731⟩—Dry it at 100° to constant weight:

it loses not more than 7.0% of its weight.Coagulable protein—Heat a filtered solution (1 in 20) toAdd the following:

boiling: no precipitate forms.Microbial content—NMT 104 cfu/g▲ Pentafluoropropanoic Acid (Pentafluoropropionic Acid),

C3HF5O2—164.03 [422-64-0]—Use a suitable grade with a Bacteriological test (for growth promotion and freedomcontent of NLT 97%.▲ USP36 from fermentable carbohydrates)—

Pentane (n-Pentane), C5H12—72.15 [109-66-0]— Medium: 2% of digest and sufficient phenol red TS toClear, colorless, flammable liquid. Very slightly soluble in give a perceptible color in water; adjust the pH to 7.2–7.4.water. Miscible with alcohol, with ether, and with many or- Place 10 mL of Medium in test tubes containing a Durhamganic solvents. Specific gravity: about 0.62. fermentation tube. Autoclave at 121° for 15 min. After

Boiling range (Reagent test)—Not less than 95% distils autoclaving and standing for 24 h, the Medium is clear.between 34° and 36°. In separate tubes for each organism, inoculate 10 mL of

1-Pentanesulfonic Acid Sodium Salt—See Sodium Medium with Escherichia coli ATCC 25922 and Enterococcus1-Pentanesulfonate. faecalis ATCC 12953. Incubate at 35 ± 2° for 48 h.

2-Pentanone, C5H10O—86.13 [107-87-9]—Use a suita- It meets the following criteria for bacteria-nutrient proper-ble grade. ties: Escherichia coli ATCC 25922 and Enterococcus faecalis

Pepsin [9001-75-6]—Use Pepsin (Enzyme Preparations) ATCC 12953 growth evident, no acid or only a trace in theFCC, having an activity of 1.0 to 1.17 Pepsin units per mg. inner tube, and no gas produced after incubation at 48 h.Pepsin of higher activity may be reduced to this activity by Peptone, Dried (Meat Peptone)—Reddish-yellow toadmixture with pepsin of lower activity or with lactose. brown powder, having a characteristic, but not putrescent,

Pepsin, Purified—A white or yellowish-white powder, odor. Soluble in water, forming a yellowish-brown solutionspongy mass, or translucent scales or granules. Freely solu- having a slight acid reaction; insoluble in alcohol and inble in water, producing more or less opalescence; practically ether.insoluble in alcohol, in chloroform, and in ether. Purified Nitrogen content (Reagent test)—Determine by thePepsin used in the second tier of the Dissolution test has an Kjeldahl method, using a test specimen previously dried atactivity that is determined by the following method. 105° to constant weight: between 12% and 18% of nitro-

Activity— gen is found.PEPSIN SOLUTION—Transfer about 2.5 mg of Purified Pepsin, Residue on ignition (Reagent test)—Ignite 500 mg with

accurately measured, to a 100-mL volumetric flask, dilute 1 mL of sulfuric acid: the residue weighs NMT 75 mgwith 10 mM hydrochloric acid to volume, and mix. [NOTE— (15.0%).Prepare immediately before use.]


Loss on drying ⟨731⟩—Dry it at 105° to constant weight: 0.1 N sulfuric acid, representing this difference, is equivalentit loses not more than 7.0% of its weight. to 11.91 mg of C6H5NCO: not less than 97.0% of C6H5NCO

is found.Coagulable protein—Heat a filtered solution (1 in 20) to2-Phenylacetamide (α-Phenylacetamide), C8H9NO—boiling: no precipitate forms.

135.16 [103-81-1]—Bimorphous plates or leaflets.Microbial content—NMT 104cfu/g Slightly soluble in water. Use a suitable grade.Perchloric Acid (70 Percent Perchloric Acid), HClO4—Melting range ⟨741⟩: between 156° and 158°.100.46 [7601-90-3]—Use ACS reagent grade (containing

dl-Phenylalanine, C9H11NO2—165.19 [150-30-1]—between 69.0% and 72.0% of HClO4).Use a suitable grade.Periodic Acid, H5IO6—227.94 [10450-60-9]—White to

o-Phenylenediamine Dihydrochloride, C6H8N2 · 2HCl—pale yellow crystals. Very soluble in water. Undergoes slow181.1—White powder.decomposition to iodic acid. Use ACS reagent grade.

Petroleum Benzin—See Hexane, Solvent. Assay—When tested by thin-layer chromatography, withPhases for Gas Chromatography—See phases for gas the use of plates coated with chromatographic silica gel

chromatography in the Chromatographic Columns section mixture and a developing system consisting of a mixture ofunder Chromatography ⟨621⟩. butyl alcohol, water, and acetic acid (12:5:3), and examined

Phenacetin [62-44-2]—Use a suitable grade. under short-wavelength UV light, a single spot is exhibited,1,10-Phenanthroline (Orthophenanthroline), C12H8N2 · with trace impurities.

H2O—198.22 [5144-89-8]—Use ACS reagent grade. p-Phenylenediamine Dihydrochloride—See p-Phenylene-o-Phenanthroline Monohydrochloride Monohydrate, diamine Hydrochloride.

C12H8N2 · HCl · H2O—234.69 [3829-86-5]—Use a suitable p-Phenylenediamine Hydrochloride (1,4-Diaminobenzenegrade. Dihydrochloride), C6H8N2 · 2HCl—181.06—White to pale tan

Phenol [108-95-2]—Use ACS reagent grade. crystals or crystalline powder, turning red on exposure toPhenol Red, Sodium, C19H13O5SNa—376.4 air. Freely soluble in water; slightly soluble in alcohol and in

[34487-61-1]—Red to brown powder. Use ACS reagent ether. Preserve in well-closed containers, protected fromgrade. light.

Phenolsulfonphthalein—Use Phenol Red (see Indicators Insoluble matter—Dissolve 1 g in 10 mL of water: the so-under Indicators and Indicator Test Papers). lution is clear and complete.

Phenoxybenzamine Hydrochloride [N-(2-Chloroethyl)-N- Molar absorptivity (see Spectrophotometry and Light-(1-methyl-2-phenoxyethyl)benzylamine Hydrochloride], scattering ⟨851⟩)—Dissolve 60 mg in 100.0 mL of water, andC18H22ClNO · HCl—340.29 [63-92-3]—White, crystalline mix. Pipet 2 mL of this solution into a 50-mL volumetricpowder. flask, dilute with pH 7 buffer solution to volume, and mix.Melting range ⟨741⟩: between 137° and 140°. The molar absorptivity of this solution, at 239 nm, is notAbsorptivity—Its absorptivity, 1%, 1 cm, in the range of less than 9000.

272 nm to 290 nm, in chloroform solution is about 178. Phenylglycine (D(−)-2-Phenylglycine),3-Phenoxybenzoic Acid, C13H10O3—214.22 (C6H5CH(NH2)COOH)—151.17 [875-74-1]—Use a suita-

[3739-38-6]—Use a suitable grade. ble grade.Phenylhydrazine, C6H5NHNH2—108.14 [100-63-0]—Melting range ⟨741⟩: between 149° and 150°.

A colorless, or slightly yellowish, highly refractive liquid.2-Phenoxyethanol, C6H5OCH2CH2OH—138.16[NOTE—Protect from light, and distill under reduced pres-[122-99-6]—Colorless, slightly viscous liquid. Soluble insure shortly prior to use.]water. Miscible with alcohol, with acetone, and with glyc-

erin. Density: about 1.107. Congealing temperature ⟨651⟩: not below 16°.Assay—To 2 g, accurately weighed, add 10 mL of a Insoluble matter—Shake 1 mL with 20 mL of diluted ace-

freshly prepared solution made by dissolving 25 g of acetic tic acid: the resulting solution is clear or practically so.anhydride in 100 g of anhydrous pyridine. Swirl to mix the Residue on ignition (Reagent test)—Ignite 1 mL withliquids, heat on a steam bath for 45 minutes, add 10 mL of 0.5 mL of sulfuric acid: the residue weighs not more thanwater, heat for 2 additional minutes, and cool. Add 10 mL 1 mg (0.1%).of normal butyl alcohol, shake vigorously, add phenol- Phenylhydrazine Hydrochloride, C6H5NHNH2 · HCl—phthalein TS, and titrate with 1 N sodium hydroxide VS. 144.60 [59-88-1]—White or yellowish crystals or powder.Perform a blank test using the same quantities of the same Soluble in water and in alcohol. Store in tight containers,reagents, and in the same manner, and make any necessary protected from light. Use a suitable grade with a content ofcorrection. Each mL of 1 N sodium hydroxide is equivalent not less than 99%.to 138.2 mg of C8H10O2. Not less than 99% is found. Phenylmethylsulfonyl Fluoride, C7H7FO2S—174.2

Phenol—Add 0.2 mL of it to 20 mL of water, mix, and to [329-98-6]—White to faint yellow powder. Use a suitable5 mL of the mixture add 0.2 mL of Millon’s reagent. Warm grade.the solution at 60° for 90 seconds, and allow to stand: no [NOTE—A suitable grade is available from Sigma-Aldrich,pink or red color is produced within 1 minute. www.sigma-aldrich.com.]

Phenyl Ether—See Diphenyl Ether. 3-Phenylphenol (m-Phenylphenol), C6H5C6H4OH—170.21Phenyl Isocyanate, C6H5NCO—119.12 [103-71-9]— [580-51-8]—White to off-white, crystalline powder.

Clear, colorless to straw-yellow liquid of medium volatility. Assay—Inject an appropriate specimen into a suitable gas[CAUTION—Phenyl Isocyanate is a violent lacrimator, and the chromatograph (see Chromatography ⟨621⟩) equipped withvapor is highly toxic. Handle with care.] a flame-ionization detector, helium being used as the carrier

Assay—Transfer 250 mg, accurately weighed, to a glass- gas. The following conditions have been found suitable: astoppered, 250-mL flask. Exercise care to avoid loss by vola- 0.25-mm × 30-m capillary column coated with G1; the in-tilization, and avoid breathing the vapor. Add 20 mL of bu- jection port temperature is maintained at 250°; the columntylamine solution (25 g of butylamine diluted to 1000 mL temperature is maintained at 150° and programmed to risewith dioxane previously dried over potassium hydroxide pel- 15° per minute to 250°; and the detector temperature islets), insert the stopper in the flask, and allow to stand for maintained at 310°. The area of the 3-phenylphenol peak is15 minutes. Add a few drops of methyl red TS and 25 mL of not less than 98% of the total peak area.water, and titrate the excess amine with 0.1 N sulfuric acid Melting range ⟨741⟩: between 76° and 79°.VS. Perform a blank titration on 20 mL of the butylamine Phloroglucinol, C6H3(OH)3 · 2H2O—162.14solution (see Residual Titrations ⟨541⟩). Subtract the volume [6099-90-7]—White or yellowish-white crystals or a crystal-of 0.1 N sulfuric acid consumed in the test specimen titra- line powder. Soluble in alcohol and in ether; slightly solubletion from that consumed in the blank titration. Each mL of in water.


Insoluble in alcohol—Dissolve 1 g in 20 mL of alcohol: a Nitrate—Dissolve 500 mg in 10 mL of water, and addclear and complete solution results. about 10 mg of sodium chloride, 0.1 mL of indigo carmine

TS, and 10 mL of sulfuric acid: the blue color does not dis-Melting range, Class Ia ⟨741⟩: between 215° and 219°.appear within 1 minute (about 0.01%).Residue on ignition (Reagent test)—Ignite 1 g with 0.5 mL

Sulfate (Reagent test, Method I )—A 500-mg portionof sulfuric acid: the residue weighs not more than 1 mgshows not more than 0.1 mg of SO4 (0.02%).(0.1%).

o-Phthalaldehyde (Phthalic Dicarboxaldehyde),Diresorcinol—Heat to boiling a solution of 100 mg in C6H4(CHO)2—134.13 [643-79-8]—Use a suitable grade.10 mL of acetic anhydride, cool the solution, and superim- Phthalazine, C8H6N2—130.15 [253-52-1]—Yellow topose it upon 10 mL of sulfuric acid: no violet color appears tan crystals.at the zone of contact of the liquids.Melting range ⟨741⟩: between 89° and 92°.Phloxine B (Acid red 92; Eosin 10B; 2’,4’,5’,7’-tetrabromo-

Phthalic Acid, C8H6O4—166.13 [88-99-3]—Use ACS4,5,6,7-tetrachlorofluorescein disodium salt)reagent grade.C20H2Br4Cl4Na2O5—829.63 [18472-87-2]—Use a suitable

Phthalic Anhydride, C8H4O3—148.12 [85-44-9]—Usegrade with a dye content of not less than 80%, certified byACS reagent grade.the Biological Stain Commission.

Phthalimide, C8H5NO2—147.13 [85-41-6]—WhitePhosphatase Enzyme, Alkaline—Use a suitable gradepowder.from intestinal origin.

[NOTE—A suitable grade is available from Worthington Assay—Biochemical Corp., www.worthington-biochem.com.] MOBILE PHASE—Prepare a mixture of isooctane and methyl-

Phosphatic Enzyme—An enzyme preparation of microbial tert-butyl ether (88:12).origin, high in both phosphatase and amylase activity, the PROCEDURE—Inject about 20 µL into a suitable liquid chro-former being the property that renders it suitable for use in matograph (see Chromatography ⟨621⟩) equipped with athe liberation of thiamine from its orthophosphate and py- 230-nm detector and a 4.6-mm × 15-cm column that con-rophosphate esters. Light cream-colored or slightly gray tains packing L3. The flow rate is about 2 mL per minute.powder. Freely soluble in water. It hydrolyzes 300 times its The area of the C8H5NO2 peak is not less than 99% of theweight of starch in 30 minutes. total peak area.

Amylase activity—Place in a test tube 5 mL of a 1 in 50 Melting range ⟨741⟩: between 233° and 235°, with de-solution of soluble starch in 0.2 M, pH 5 sodium acetate composition.buffer (containing 1.6 g of anhydrous sodium acetate in 2-Picoline, C6H7N—93.13 [109-06-8]—Colorless toeach L and sufficient glacial acetic acid to adjust to a pH of yellowish liquid.5), and add 4 mL of water. Mix, and place in a water bathAssay—Inject an appropriate specimen into a suitable gasat 40°. Add 1 mL of a solution containing 0.3 mg of the

chromatograph (see Chromatography ⟨621⟩) equipped withphosphatic enzyme, mix, and note the exact time. Aftera flame-ionization detector, helium being used as the carrier30 minutes remove 1.0 mL of the mixture, and add it togas. The following conditions have been found suitable: a5.0 mL of 0.0005 N iodine in a 20- × 150-mm test tube: a2-mm × 2-m glass column packed with 20% liquid phaseclear, red color results.G16 on 80- to 100-mesh support S1C; the injection portPhosphomolybdic Acid, approximately 20MoO3 · P2O5 ·temperature is maintained at 140°; the detector tempera-51H2O—3939.49 [11104-88-4]—Use ACS reagent grade.ture is maintained at 300°; the column temperature is main-Phosphoric Acid, H3PO4—98.00 [7664-38-2]—Usetained at 90° and programmed to rise 3° per minute toACS reagent grade.140°. The area of the C6H7N peak is not less than 98% ofPhosphorous Acid (Phosphonic Acid), H3O3P—82.00the total peak area.[13598-36-2]—Use a suitable grade with a content of not

Refractive index ⟨831⟩: 1.500 ± 0.002 at 20°.less than 99%.Picric Acid (2,4,6-Trinitrophenol; Trinitrophenol),Phosphorus, Red, P—At. Wt. 30.97376—A dark red

C6H2(OH)(NO2)3-1,2,4,6—229.10 [88-89-1]—Use ACS re-powder. Insoluble in water and in dilute acids; soluble inagent grade.dehydrated alcohol.

Picrolonic Acid (3-Methyl-4-nitro-1-(p-nitrophenyl)-Yellow phosphorus—Shake 20 g with 75 mL of carbon di-5-pyrazolone), C10H8N4O5—264.19 [550-74-3]—Yellow tosulfide in a glass-stoppered vessel, and allow to stand in thebrownish-yellow, crystalline powder. Slightly soluble indark overnight. Filter, and wash the residue with carbon di-water; soluble in alcohol, in chloroform, in ether, in ben-sulfide until the filtrate, collected in a graduated cylinder,zene, and in solutions of alkali hydroxides.measures 100 mL. Evaporate the solvent to 10 mL by im-

Melting range ⟨741⟩: between 115° and 117°.mersing the cylinder in hot water. Dip a strip of cupric sul-fate test paper in the remaining solvent: no more color is Residue on ignition (Reagent test): negligible, fromproduced than in a similar strip dipped into 10 mL of solu- 200 mg.tion in carbon disulfide containing 3 mg of yellow phos- Sensitiveness—Dissolve 25 mg in 10 mL of warm waterphorus (0.015% as P). containing 0.1 mL of glacial acetic acid, and filter the solu-

Soluble substances—Digest 2 g with 30 mL of acetic acid tion, if necessary. Dissolve 100 mg of calcium chloride inon a steam bath for 15 minutes. Cool, dilute with water to 250 mL of water, and mix. Heat 1 mL of the calcium chlo-40 mL, and filter. Evaporate 20 mL of the filtrate on a steam ride solution in a test tube to about 60°, then add to itbath, and dry at 105° for 2 hours: the residue weighs not 1 mL of the picrolonic acid solution: a bulky precipitatemore than 6 mg (0.6%). forms in 5 minutes or less.

Phosphorus Pentoxide (Phosphoric Anhydride), P2O5— Pipemidic Acid (8-Ethyl-3,8-dihydro-5-oxo-2-(1-piper-141.94 [1314-56-3]—Use ACS reagent grade. azinyl)pyrido[2,3-d]-pyrimidine-6-carboxylic acid),

Phosphotungstic Acid, approximately 24WO3 · P2O5 · C14H17N5O3—303.3 [51940-44-4]—Use a suitable grade.51H2O—6624.84—White or yellowish-green crystals or a Piperazine (Diethylenediamine), C4H10N2 · 6H2O—crystalline powder. Soluble in water, in alcohol, and in 194.23—Use a suitable grade.ether. Piperidine, C5H11N—85.15 [110-89-4]—Colorless liq-

uid. Miscible with water and with alcohol. Specific gravity:Insoluble matter (Reagent test): not more than 1 mg,about 0.860.from 5 g (0.02%).

Chloride (Reagent test)—One g shows not more than0.3 mg of Cl (0.03%).


Congealing range ⟨651⟩: between 12° and 15°. Residue on ignition: not more than 0.75%.[NOTE—Suitable grades are available as catalog number UBoiling range (Reagent test)—Not less than 95% distills

232, from J.T. Baker Chemical Co., www.jtbaker.com.]between 104° and 106°.Potassium Acetate, KC2H3O2—98.14 [127-08-2]—UseRefractive index: about 1.454. ACS reagent grade.Platinic Chloride (Chloroplatinic Acid), H2PtCl6 · 6H2O— Potassium Alum—Use Potassium Alum [see Potassium517.90 [18497-13-7]—Use ACS reagent grade Chloropla- Alum (USP monograph)].tinic Acid. Potassium Arsenate Monobasic, KH2AsO4—180.03Polydimethylsiloxane, viscosity 0.65 centistokes (Hexa- [7784-41-0]—Use a suitable grade with a content of NLTmethyldisiloxane), (CH3)3SiOSi(CH3)3—162.38 98%.[107-46-0]—Liquid. Freezes at about 0°. Potassium Bicarbonate, KHCO3—100.12

Refractive index ⟨831⟩: about 1.3770. [298-14-6]—Use ACS reagent grade.Specific gravity ⟨841⟩: about 0.760. Potassium Biphosphate—See Potassium Phosphate, Mono-

Polyethylene Glycol 200, H(OCH2CH2)nOH in which the basic.average value of n is 4—average molecular weight 200 Potassium Biphthalate (Acid Potassium Phthalate; Phthalic[25322-68-3]—Clear, colorless or almost colorless, viscous, Acid Monopotassium Salt; Potassium Hydrogen Phthalate Acidi-hygroscopic liquid. Very soluble in acetone and in alcohol; metric Standard), KHC6H4(COO)2—204.22 [877-24-7]—practically insoluble in ether and in fatty oils. Use a suitable Use ACS reagent grade Potassium Hydrogen Phthalate, Aci-grade. dimetric Standard.

Potassium Bisulfate, KHSO4—136.17 [7646-93-7]—Refractive index ⟨831⟩: 1.4590 at 20°.Fused, white, deliquescent masses or granules. Very solubleDensity: 1.127 at 25°.in water. When ignited, it evolves SO3 and H2O, changingViscosity: 4.3 centistokes at 98.9°. first to potassium pyrosulfate, then to sulfate.Polyethylene Glycol 600 [25322-68-3]—A clear, practi-

Acidity—Dissolve 4 g, accurately weighed, in 50 mL ofcally colorless, viscous liquid condensation polymer repre-water, add phenolphthalein TS, and titrate with 1 N alkali: itsented by H(OCH2CH2)nOH, in which n varies from 12 tocontains between 34% and 36%, calculated as H2SO4.14. Its average molecular weight is about 600.

Insoluble matter and ammonium hydroxide precipitate—It meets the requirements of all of the tests under Polyeth-Dissolve 10 g in 100 mL of water, add methyl red TS, renderylene Glycol (NF monograph) except Limit of ethylene glycolslightly alkaline with ammonia TS, boil for 1 minute, andand diethylene glycol.digest on a steam bath for 1 hour. Pass through a taredPolyethylene Glycol 20,000 [25322-68-3]—Molecularfiltering crucible, wash thoroughly, and dry at 105° forweight range: 15,000–20,000. Hard, white, waxy solid, usu-2 hours: the precipitate weighs not more than 1 mgally supplied in flake form. Soluble in water with subsequent(0.01%).gel formation.

For the following tests, prepare a Test solution as follows.Viscosity of 25% solution ⟨911⟩—Add 50.0 g of test speci-Dissolve 6 g in 45 mL of water, add 2 mL of hydrochloricmen to a 250-mL wide-mouth, screw-cap jar containingacid, boil gently for 10 minutes, cool, and dilute with water150.0 g of water. Attach the cap securely to the jar, and rollto 60 mL.on a mechanical roller until the test specimen is completely

Heavy metals (Reagent test)—To 30 mL of Test solutiondissolved, in 2 to 4 hours. Allow the solution to stand untiladd phenolphthalein TS, and neutralize with ammonia TS.all air bubbles have disappeared. Another 2 to 4 hours mayAdd 0.5 mL of glacial acetic acid, dilute with water tobe required. Adjust the temperature of the solution to 37.840 mL, and add 10 mL of hydrogen sulfide TS: any brown± 0.1°, and determine the kinematic viscosity on a suitablecolor produced is not darker than that of a control contain-viscometer of the Ubbelohde type. The viscosity is not lessing 10 mL of Test solution and 0.02 mg of added Pbthan 100 centistokes.(0.001%).pH ⟨791⟩: between 6.5 and 8.0 in a solution (1 in

Iron ⟨241⟩—To 5 mL of Test solution add 2 mL of hydro-20). [NOTE—A five-fold dilution of the test solution preparedchloric acid, and dilute with water to 47 mL: the solutionfor the Viscosity of 25% solution test may be used.]shows not more than 0.01 mg of Fe (0.002%).Residue on ignition ⟨281⟩: not more than 0.7%, the

Potassium Bromate, KBrO3—167.00 [7758-01-2]—use of sulfuric acid being omitted.Use ACS reagent grade.Polyoxyethylene (23) Lauryl Ether (Brij-35)—Use a suita-

Potassium Bromide, KBr—119.00 [7758-02-3]—Useble grade.ACS reagent grade.[NOTE—A suitable grade is available commercially as “Brij-

Potassium Carbonate—See Potassium Carbonate, Anhy-35.”]drous.Polyoxyethylene (20) Sorbitan Monolaurate

Potassium Carbonate, Anhydrous, K2CO3—138.21[9005-64-5]—Viscous, light yellow to yellow-green liquid.[584-08-7]—Use ACS reagent grade.Use a suitable grade.

Potassium Chlorate, KClO3—122.55 [3811-04-9]—Polysaccharide Molecular Weight Standards—Use ACS reagent grade.Polymaltotriose polymers of different weight-average molec-

Potassium Chloride, KCl—74.55 [7447-40-7]—Useular weight, MW, values ranging from 5,000 to 400,000 Da.ACS reagent grade.[NOTE—A suitable set is available from Shodex (www.

Potassium Chloroplatinate, K2PtCl6—485.99—Heavy,shodex.com) as Kit P-82.]yellow powder. Soluble in hydrochloric acid and in nitricPolystyrene Cation–Exchange Resin—See Ca-acid.tion–Exchange Resin, Polystyrene.

Assay—Accurately weigh about 300 mg, transfer to aPolytef—Use Poly(tetrafluoroethylene).600-mL beaker, add 20 mL of hydrochloric acid, and heatPolyvinyl Alcohol, (C2H4O)n [9002-89-5]—White pow-gently if necessary to achieve complete solution. Add zincder. Soluble in water; insoluble in organic solvents.granules, slowly, until no more dissolves, then add 2 mL ofpH ⟨791⟩: between 5.0 and 8.0, in a solution (1 inhydrochloric acid, and digest for 1 hour on a steam bath to25).coagulate the reduced platinum. Add more acid, if neces-Loss on drying—Dry it at 110° to constant weight: it loses sary, to ensure that all of the zinc has dissolved. Filternot more than 5% of its weight. through paper, rinsing the beaker with diluted hydrochloricacid until all of the precipitate is transferred to the filter,then wash with several small portions of water. Ignite thefilter in a tared crucible at 800 ± 25° to constant weight.


Each mg of residue is equivalent to 1.0 mg of platinum. Not Potassium Metabisulfite (Potassium Disulfite; Potassiumless than 40% is found. Pyrosulfite), K2S2O5—222.32 [16731-55-8]—Use a suitable

Potassium Chromate, K2CrO4—194.19 [7789-00-6]— grade with a content of not less than 98%.Use ACS reagent grade. Potassium Nitrate, KNO3—101.10 [7757-79-1]—Use

Potassium Cyanide, KCN—65.12 [151-50-8]—Use ACS reagent grade.ACS reagent grade. Potassium Nitrite, KNO2—85.10 [7758-09-0]—Use

Potassium Dichromate, K2Cr2O7—294.18 ACS reagent grade.[7778-50-9]—Use ACS reagent grade. Potassium Perchlorate, KClO4—138.55

[NOTE—Potassium dichromate of a quality suitable as a [7778-74-7]—Use ACS reagent grade.primary standard is available from the National Institute of Potassium Periodate (Potassium meta-Periodate), KIO4—Standards and Technology, Washington, DC, www.nist.gov, 230.00 [7790-21-8]—Use ACS reagent grade.as standard sample No. 136.] Potassium Permanganate, KMnO4—158.03

Potassium Ferricyanide, K3Fe(CN)6—329.24 [7722-64-7]—Use ACS reagent grade.[13746-66-2]—Use ACS reagent grade. Potassium Persulfate, K2S2O8—270.32 [7727-21-1]—

Potassium Ferrocyanide, K4Fe(CN)6 · 3H2O—422.39 Use ACS reagent grade Potassium Peroxydisulfate.[14459-95-1]—Use ACS reagent grade. Potassium Phosphate, Dibasic (Dipotassium Hydrogen

Potassium Hyaluronate—White to cream-colored pow- Phosphate; Dipotassium Phosphate), K2HPO4—174.18der. Freely soluble in water. Store in a tight container, in a [7758-11-4]—Use ACS reagent grade.refrigerator. Potassium Phosphate, Dibasic, Trihydrate (Dipotassium

Hydrogen Phosphate Trihydrate; Dipotassium Phosphate),Inhibitor content—Prepare as directed in the Assay underK2HPO4 · 3H2O—228.22 [16788-57-1]—Use a suitableHyaluronidase for Injection (USP monograph) a quantity ofgrade with a content of NLT 99.0%.Standard solution containing 1 USP Hyaluronidase Unit in

Potassium Phosphate, Monobasic (Potassiumeach mL, and a similar quantity of acetate-buffered StandardBiphosphate; Potassium Dihydrogen Phosphate), KH2PO4—solution using as the solvent 0.1 M, pH 6 sodium acetate136.09 [7778-77-0]—Use ACS reagent grade.buffer (prepared by diluting the 0.2 M buffer prepared as

[NOTE—Certified Potassium Dihydrogen Phosphate is avail-directed below with an equal volume of water). Prepareable from the National Institute of Standards and Technol-from the potassium hyaluronate under test 10 mL of Potas-ogy, Washington, DC, www.nist.gov, as standard samplesium hyaluronate stock solution, and dilute 2 mL of it withNo. 186.]the specified Phosphate buffer solution to make a Hyaluronate

Potassium Phosphate, Tribasic, K3PO4—212.27solution. In the same way, and concurrently, dilute a second[7778-53-2]—Deliquescent, orthorhombic crystals. Use ACS2-mL portion of the stock solution with 0.2 M, pH 6 sodiumreagent grade.acetate buffer (containing 16.4 g of anhydrous sodium ace-

Potassium Pyroantimonate (Potassium hexahydroxyan-tate and 0.45 mL of glacial acetic acid in each 1000 mL).timonate), KSb(OH)6—262.90 [12208-13-8]—White crys-Place 0.50-mL portions of the Hyaluronate solution in eachtals or a white, crystalline powder. Sparingly soluble inof four 16- × 100-mm test tubes, and place 0.50-mL por-water. Use a suitable grade.tions of the acetate-buffered Hyaluronate solution in two sim-

Potassium Pyrophosphate, K4P2O7—330.34ilar tubes. To two of the four tubes containing Hyaluronate[7320-34-5]—Colorless, deliquescent granules. Freely solublesolution add 0.50 mL of Diluent for hyaluronidase solutions,in water; insoluble in alcohol.prepared as directed in the Assay under Hyaluronidase for

Potassium Pyrosulfate [7790-62-7]—Usually available asInjection (USP monograph). To the remaining two tubes, ona mixture of potassium pyrosulfate (K2S2O7) and potassiuma rigid schedule, at 30-second intervals, add 0.50 mL ofbisulfate (KHSO4). Use ACS reagent grade.Standard solution. Similarly, to the two tubes containing ace-

Potassium Sodium Tartrate, KNaC4H4O6 · 4H2O—282.22tate-buffered Hyaluronate solution add at 30-second intervals[6381-59-5]—Use ACS reagent grade.0.50-mL portions of acetate-buffered Standard solution. Then

Potassium Sulfate, K2SO4—174.26 [7778-80-5]—Useproceed as directed in the second paragraph for Procedure,ACS reagent grade.beginning with “Mix the contents,” as far as “Plot the aver-

Potassium Tellurite (Potassium Tellurate IV), K2TeO3—age.” The reduction in absorbance of acetate-buffered Hy-253.79 [7790-58-1]—White, granular powder. Soluble inaluronate solution is not less than 25% of that observed inwater. Its solution is alkaline.the Hyaluronate solution.

Assay—Weigh accurately about 120 mg, transfer to aTurbidity production—The average absorbance of the solu-beaker, and dissolve in a mixture of 10 mL of nitric acid,tions in the two tubes containing Hyaluronate solution and10 mL of sulfuric acid, and 25 mL of water. Heat to boiling,Diluent for hyaluronidase solutions prepared in the test forand boil until copious fumes of sulfur trioxide are evolved.Inhibitor content is not less than 0.26 at a wavelength ofCool, cautiously add 100 mL of water, heat to boiling, add640 nm in a suitable spectrophotometer using a 1-cm cell.6 g of sodium fluoride, and titrate the hot solution withPotassium Hydrogen Sulfate, KHSO4—136.17—White0.1 N potassium permanganate VS. Each mL of 0.1 N potas-crystals. Soluble in water.sium permanganate is equivalent to 12.69 mg of K2TeO3.Melting point ⟨741⟩: about 197°. Not less than 98% is found.Potassium Hydroxide, KOH—56.11 [1310-58-3]—Use

Chloride (Reagent test)—One g shows not more thanACS reagent grade.0.1 mg of Cl (0.01%).Potassium Iodate, KIO3—214.00 [7758-05-6]—Use

Potassium Thiocyanate, KSCN—97.18 [333-20-0]—ACS reagent grade.Use ACS reagent grade.Potassium Iodide, KI—166.00 [7681-11-0]—Use ACS

Potato Starch—See Starch, Potato.reagent grade.Propionaldehyde, C3H6O—58.08 [123-38-6]—Use a

suitable grade.Propionic Anhydride, C6H10O3—130.14 [123-62-6]—

Colorless liquid. Is decomposed by water. Soluble in metha-nol, in alcohol, in ether, and in chloroform.

Assay—Accurately weigh about 350 mg into a tared,glass-stoppered flask containing 50 mL of dimethylform-amide previously neutralized to the thymol blue endpointwith 0.1 N sodium methoxide in methanol VS. Titrate with0.1 N sodium methoxide in methanol VS to the thymol blueendpoint. Perform a blank determination, and make any


necessary correction. Each mL of 0.1 N sodium methoxide is Glucose standard solution—Dry anhydrous glucose crystalsequivalent to 13.014 mg of C6H10O3. Not less than 97.0% is under less than 50-mm Hg at 60° for 5 hours, and calculatefound. the water content. Transfer 10.00 g of dried glucose to a 1-L

volumetric flask, dissolve in and dilute with water to vol-Refractive index ⟨831⟩: between 1.4035 and 1.4045 atume, and mix. Transfer 10.0 mL to a 1-L volumetric flask20°.and dilute to volume with water. Each mL contains 100 µgPropiophenone, C9H10O—134.18 [93-55-0]—Use aof glucose.suitable grade.

iso-Propyl Alcohol—See Isopropyl Alcohol. Pullulanase diluent—Dilute pullulanase with Buffer solutionn-Propyl Alcohol (1-Propanol), CH3CH2CH2OH—60.10 B, pH 6.0 to prepare a solution having the enzyme activity

[71-23-8]—Use ACS reagent grade. of about 0.2 units per mL. [NOTE—The measurement rangePropylamine Hydrochloride (1-Propanamine hydrochlo- is between 0.1 and 0.4 units per mL.] Record the dilution

ride; n-Propylamine hydrochloride), C3H9N · HCl—95.57 factor (FPD). This diluent is used as a diluted enzyme solu-[556-53-6]—Use a suitable grade with a content of not less tion.than 99%. Procedure—Transfer 4 mL of Substrate to a test tube and

Protein Molecular Weight Standard—Also known as add 0.5 mL of Buffer solution A, pH 5.0,mix, and incubate atprotein molecular weight markers (for SDS-PAGE) and con- 30°. Add 0.5 mL of Pullulanase diluent, and mix thoroughly.sists of a mixture of several proteins of well-defined molecu- After 30 seconds, transfer 1 mL of this solution to a test tubelar weights. The products are generally available in a suita- labeled as “Pullulan test solution 1”, and add 2 mL of Somo-ble buffer containing a suitable reducing agent (generally, gyi reagent, and mix. After 30 minutes and 30 seconds,100 mM DTT), a preservative (for example, sodium azide), transfer 1 mL of the mixture of Substrate and Pullulanase di-and 50% glycerol to prevent freezing. Use a suitable grade. luent to a second test tube labeled as “Pullulan test solutionStore at –20°. 2”, add 2 mL of Somogyi reagent, and mix. In a third test

Protein Standard Solution (8 g/dL)—A solution contain- tube labeled as “Standard blank”, mix 2 mL of Somogyi rea-ing 5 g of Albumin Human and 3 g of human gamma glob- gent and 1 mL of water. In a fourth test tube labeled asulin per dL. “Glucose standard solution”, mix 2 mL of Somogyi reagent

[NOTE—A suitable grade is available as Protein Standard and 1 mL of Glucose standard solution, and add 1 mL ofSolution, catalog number 540-10, from Sigma-Aldrich, water. Incubate the fourth test tube in a boiling water bathwww.sigma-aldrich.com.] for exactly 10 minutes. Remove the tube and allow it to

Protocatechuic Acid (3,4-Dihydroxybenzoic acid), cool in cold running water. Add 2 mL of Nelson reagent, mixC7H6O4—154.12 [99-50-3]—Use a suitable grade. well, and allow the solution to stand for at least 15 minutes.

Pullulanase (Amylopectin-6-gluconohydrolase) Add 5 mL of water to each of the four test tubes, and mix[9075-68-7]—An enzyme obtained from Kleibsiella thoroughly. Determine the absorbance at 520 nm of thepneumoniae. It contains not less than 30 units per mg of Standard blank, Ablank, of the Glucose standard solution, AStd,protein. One unit defined for enzymatic activity will liberate of the Pullulan test solution 1, A0, and of the Pullulan test1.0 µmol of maltotriose (measured as glucose) from pullulan solution 2, A30, using water as the blank. One unit is definedper minute at pH 5.0 at 30°. It can be suspended in 3.2 M as the enzymatic activity that produces 1 µmol of maltotri-ammonium sulfate solution, pH 6.2. ose (measured as glucose) from pullulan per minute. Calcu-Measurement of relative pullulanase activity— late the pullulanase activity, PA, in units per mL, using the

formula:DETERMINATION OF PULLULANASE ACTIVITY—Substrate—Dissolve pullulan1 in water to make a 1.25% PA = [(A30 − A0)/(AStd − Ablank)] × 0.185 × FPD(w/v) solution. [NOTE—Add pullulan to the water. Clumping

will occur if water is added to pullulan.]MEASUREMENT OF PROTEIN AMOUNT (MEASURED AS ALBUMINOIDBuffer solution A, pH 5.0—Add 0.1 M disodium phosphate AMOUNT) FOR THE CALCULATION OF SPECIFIC ACTIVITY—(27 g of dibasic sodium phosphate in each L of the solution)

Reagent A—Prepare a solution having known concentra-to 0.1 M citric acid (21 g of citric acid in each L of thetions of about 0.1 N sodium hydroxide and about 0.2 Msolution) to adjust pH to 5.0.sodium carbonate.Buffer solution B, pH 6.0—Add diluted acetic acid to 1 M

Reagent B—Transfer 0.5 g of cupric sulfate and 1.0 g ofsodium acetate (136 g of sodium acetate in each L of solu-sodium citrate dihydrate to a 100-mL volumetric flask, dis-tion) to adjust the pH to 6.0. Dilute with water to preparesolve in and dilute with water to volume, and mix.the final buffer solution as 0.01 M acetic acid buffer, pH

Lowry solution—Mix Reagent A and Reagent B at the pro-6.0.portion of 50:1.Somogyi reagent—Add 54 g of disodium phosphate

Diluted Folin-Ciocalteu’s phenol reagent (for albuminoidheptahydrate or 28 g of anhydrous disodium hydrogenquantification)—Prepare a two-fold dilution of 2 N Folin-Cio-phosphate and 40 g of potassium sodium tartrate to aboutcalteu’s phenol reagent commercially available or prepare a650 mL of water or about 700 mL for anhydrous disodiumsolution by making an appropriate dilution from Folin-Cio-hydrogen phosphate. Add 100 mL of 1 N sodium hydroxidecalteu Phenol TS (see Method 2 in Biotechnology-Derived Arti-to this solution and mix. Add 80 mL of 10% cupric sulfatecles—Total Protein Assay ⟨1057⟩).to the solution, and mix. Heat until any solid is completely

dissolved. Add 180 g of anhydrous sodium sulfate to the Bovine serum albumin standard stock solution—Transfersolution and adjust the volume to 1 L. Allow the solution to 0.05 g of bovine serum albumin to a 500-mL volumetricstand at room temperature for 1 or 2 days to let insoluble flask, dissolve in and dilute with water to volume, and mix.matter precipitate. Filter the solution with standard filter pa- It contains 100 µg of bovine serum albumin per mL.per, and keep the solution in a brown bottle with a ground- Standard solutions—Using appropriate dilutions of Bovineglass stopper. serum albumin standard stock solution in water, prepare five

Nelson reagent—Dissolve 50 g of ammonium molybdate Standard solutions having concentration equally spaced be-in 900 mL of water. Add 42 g of sulfuric acid, and mix. Dis- tween 5 and 100 µg of bovine serum albumin per mL.solve 6 g of sodium arsenate or 3.6 g of monobasic potas- Test solution—Dilute pullulanase with Buffer solution B, pHsium arsenate in 50 g of water. Allow the solution to stand 6.0 in order to obtain a solution having a concentrationin a brown bottle with a ground-glass stopper at 37° for 1 between 60 and 70 µg of albuminoid per mL. [NOTE—Wateror 2 days. can be used as diluent.] Record the dilution factor, FTS.1A suitable supplier for pullulan is www.hayashibara-intl.com.


Blank solution—Use water. Melting range ⟨741⟩: between 149° and 153° over a2° range.Procedure—To 0.3 mL in separate tubes of the Standard

Pyridine, C5H5N—79.10 [110-86-1]—Use ACS reagentsolutions, the Test solution, and the Blank solution, add 3 mLgrade.of Lowry solution, and mix. Allow to incubate at room tem-

Pyridine, Dried [110-86-1]—Use ACS reagent grade.perature for 10 minutes. Add 0.3 mL of Diluted Folin-Cio-Pyridoxal Hydrochloride, C8H9NO3 · HCl—203.62calteu’s phenol reagent to each tube, mix immediately, and

[65-22-5]—White to slightly yellow crystals or crystallineallow to stand at room temperature for 60 minutes. Deter-powder. Gradually darkens on exposure to air or sunlight.mine the absorbances of the Standard solutions and the TestOne g dissolves in about 2 mL of water and in about 25 mLsolution at the wavelength of maximum absorbance atof alcohol. Insoluble in acetone, in chloroform, and in ether.about 750 nm, using the Blank solution as the blank.Its solutions are acid (pH about 3).Calculation—[NOTE—The relationship of absorbance to

Melting range ⟨741⟩: between 171° and 175° withprotein concentration is nonlinear; however, if the standardsome decomposition.curve concentration range is sufficiently small, it will ap-

proach linearity.] Using linear regression method, plot the Residue on ignition (Reagent test): not more than 0.1%.absorbances of the Standard solutions versus the protein (bo- Loss on drying ⟨731⟩—Dry it at 105° for 2 hours: it losesvine serum albumin) concentrations, in µg per mL, and de- not more than 0.5% of its weight.termine the best fit curve. Using the plot, determine the Nitrogen content (Reagent test)—Determine by theconcentration, Calbuminoid, in µg per mL, of protein (albumi- Kjeldahl method, using a test specimen previously dried atnoid amount) in the Test solution. Calculate the albuminoid 105° for 2 hours: between 6.7% and 7.1% of N is found.concentration, in mg per mL, in the pullulanase taken by

Chloride content—Accurately weigh about 500 mg, previ-the formula:ously dried at 105° for 2 hours, and dissolve in 50 mL ofwater. Add 3 mL of nitric acid and 50.0 mL of 0.1 N silverCprotein = (Calbuminoid × FTS)/1000nitrate VS, then add 5 mL of nitrobenzene, shake for about2 minutes, add ferric ammonium sulfate TS, and titrate theCalculate the specific activity, SA, in units per mg, of pullu-excess silver nitrate with 0.1 N ammonium thiocyanate VS:lanase using the formula:each mL of 0.1 N silver nitrate is equivalent to 3.545 mg ofCl. Between 17.2% and 17.7% is found.SA = PA/Cprotein

Pyridoxal 5-Phosphate, 4-CHOC5HN-2-CH3, 3-OH,5-CH2PO4H2 · H2O—265.16 [41468-25-1]—Light yellowPumice—A substance of volcanic origin consisting chieflypowder. Use a suitable grade.of complex silicates of aluminum and alkali metals. Occurs

Pyridoxamine Dihydrochloride, C8H12N2O2 · 2HCl—as very light, hard, rough, porous, gray masses, or as a241.11 [524-36-7]—White to slightly yellow crystals orgray-colored powder. Is insoluble in water and is not at-crystalline powder. Gradually darkens on exposure to air ortacked by diluted acids.sunlight. One g dissolves in about 1 mL of water and inAcid- and water-soluble substances—Boil 2.0 g of pow-about 60 mL of alcohol. Insoluble in chloroform and indered pumice with 50 mL of diluted hydrochloric acid underether. Its solutions are acid.a reflux condenser for 30 minutes. Cool, and filter. To half of

Melting range ⟨741⟩: between 225° and 230°, withthe filtrate add 5 drops of sulfuric acid, evaporate to dry-some decomposition.ness, ignite, and weigh: the residue weighs not more than

60 mg (6.0%). Residue on ignition (Reagent test): not more thanPurine, C5H4N4—120.11 [120-73-0]—White to off- 0.15%.

white powder. Loss on drying ⟨731⟩—Dry it at 105° for 2 hours: it losesMelting range ⟨741⟩: between 214° and 217°. not more than 0.5% of its weight.

A single spot is exhibited when it is examined by thin- Nitrogen content (Reagent test)—Determine by thelayer chromatography, with the use of plates coated with Kjeldahl method, using a test specimen previously dried atchromatographic silica gel mixture and a developing system 105° for 2 hours: between 11.3% and 11.8% of N is found.consisting of butyl alcohol, water, and glacial acetic acid Chloride content—Determine as directed in the test for(60:25:15). Chloride content under Pyridoxal Hydrochloride: betweenPutrescine Dihydrochloride, C4H12N2 · 2HCl—161.07 29.1% and 29.6% of Cl is found.[333-93-7]—White, crystalline powder. Use a suitable grade. 1-(2-Pyridylazo)-2-naphthol, C15H11N3O—249.27Pyrazole, C3H4N2 [288-13-1]—White to pale yellow crys- [85-85-8]—Stable, orange-red crystals. Soluble in alcoholtals or crystalline powder. Soluble in water, in alcohol, and and in hot solutions of dilute alkalies; slightly soluble inin ether. water.

Melting range ⟨741⟩: between 67° and 71°. Melting range ⟨741⟩: between 140° and 142°.Pyrene, C16H10—202.25 [129-00-0]—White to lightSensitiveness—Add 0.1 mL of a 1 in 1000 solution of it inyellow crystals.

alcohol to a mixture of 10 mL of water and 1 mL of a bufferAssay—Transfer about 9 mg, accurately weighed, to a solution prepared by mixing 80 mL of 0.2 M acetic acid and100-mL volumetric flask, dissolve in methanol, dilute with 20 mL of sodium acetate solution (8.2 in 100), and mix. Tomethanol to volume, and mix. Transfer 2.0 mL of this solu- this solution add 1 mL of a mixture of 1 mL of cupric sulfatetion to a 100-mL volumetric flask, dilute with methanol to TS and 2 mL of water, and mix: the color changes fromvolume, and mix. Using a suitable spectrophotometer, 1-cm yellow to red.cells, and methanol as the blank, record the absorbance of 4-(2-Pyridylazo)resorcinol (PAR), C11H9N3O2, free acid;the solution at the wavelength of maximum absorbance at C11H8N3NaO2, monosodium salt—215.21, free acid—about 238 nm. From the observed absorbance, calculate the 237.21, monosodium salt [1141-59-9,free acid;absorptivity (see Spectrophotometry and Light-scattering 16593-81-0,monosodium salt]—Use ACS reagent grade.⟨851⟩): the absorptivity is not less than 432.9, correspond- 3-(2-Pyridyl)-5,6-di(2-furyl)-1,2,4-triazine-5′,5′′-ing to not less than 98% of C16H10. disulfonic Acid, Disodium Salt (3-(2-Pyridyl)-5,6-bis(5-sulfo-2-furyl)-1,2,4-triazine, Disodium Salt Hydrate),C16H8N4Na2O8S2—494.37 [79551-14-7]—Use a suitablegrade.


[NOTE—A suitable grade is available as product number dilute with water to 47 mL: the solution shows not moreP4272 from Sigma-Aldrich, 1-800-558-9160; www.sigma- than 0.01 mg of Fe (0.002%).aldrich.com.] Quinone—See p-Benzoquinone.

Pyrogallol, C6H3(OH)3—126.11 [87-66-1]—Use ACS Rayon—Use Purified Rayon (General Monograph).reagent grade. Direct Red 80, C45H26N10Na6O21S6—1373.07

Pyrrole, C4H5N—67.09 [109-97-7]—Clear liquid, col- [2610-10-8]—Red powder. Soluble in water; poorly solubleorless when freshly distilled, becoming yellow in a few days. in alcohol. Use a suitable grade.Specific gravity: about 0.94. Insoluble in water; soluble in Red-Cell Lysing Agent—The reagent is available as a so-alcohol, in benzene, and in ether. lution containing 0.33% potassium cyanide and 0.11% so-

dium nitroprusside and a quarternary ammonium salt as theBoiling range (Reagent test)—Not less than 90% distillssurface active agent (5.5%).between 128° and 132°.

[NOTE—The reagent is manufactured by Coulter Electron-Pyruvic Acid, CH3COCOOH—88.06 [127-17-3]—Col-ics Diagnostics, Hialeah, FL and is available from many sup-orless to light yellow liquid. Miscible with water, with alco-pliers under the name of Zapoglobin (or Zap-oglobin).]hol, and with ether.

Red Phosphorus—See Phosphorus, Red.Refractive index ⟨831⟩: about 1.43 at 20°. Resazurin (Sodium), C12H6NNaO4—251.17Assay—Accurately weigh about 1 g, transfer to a suitable [62758-13-8]—A brownish-purple, crystalline powder. One

container, and add 100 mL of water. Mix, add phenol- g dissolves in 100 mL of water, forming a deep-violet-phthalein TS, and titrate with 0.5 N sodium hydroxide VS. colored solution.Each mL of 0.5 N sodium hydroxide is equivalent to Hydrogen sulfide and other compounds containing the44.03 mg of CH3COCOOH: not less than 98% of thiol group decolorize solutions of resazurin sodium, form-CH3COCOOH is found. ing dihydroresorufin. When the decolorized solution is

Quantitative Filter Paper—See Filter Paper, Quantitative. shaken in the presence of air, a rose color develops as aQuinhydrone, C6H4(OH)2 · C6H4O2—218.21 result of the formation of resorufin.

[106-34-3]—Green crystals having a metallic luster. Slightly Retinyl Palmitate, C36H60O2—524.9—Yellow liquid.soluble in cold water; soluble in hot water, in alcohol, and Assay—in ether.

Mobile phase—Prepare a mixture of acetonitrile and tetra-Assay—Transfer about 450 mg, accurately weighed, to a hydrofuran (55:15).glass-stoppered flask, add 50 mL of 1 N sulfuric acid and 3 gProcedure—Inject about 10 µL into a suitable liquid chro-of potassium iodide, insert the stopper in the flask, and

matograph (see Chromatography ⟨621⟩) equipped with ashake until dissolved. Titrate the liberated iodine with 0.1 N320-nm detector and a 4.6-mm × 15-cm column that con-sodium thiosulfate VS, adding 3 mL of starch TS as thetains packing L1. The flow rate is about 1 mL per minute.endpoint is approached. Each mL of 0.1 N sodium thiosul-The area of the C36H60O2 peak is not less than 93% of thefate is equivalent to 5.405 mg of quinone (C6H4O2). Be-total peak area.tween 49.0% and 51.0% is found.

Reverse Transcriptase—Use a suitable grade.Alcohol-insoluble matter—Dissolve 10 g in 100 mL of hot [NOTE—A suitable grade is available from BD Biosciences,alcohol, filter through a suitable tared crucible of fine poros- www.bdbiosciences.com.]ity, and wash with hot alcohol until the last washing is col- Rhodamine B (Tetraethylrhodamine), C28H31ClN2O3—orless. Dry at 105°, cool in a desiccator, and weigh: the 479.01 [81-88-9]—Green crystals or a reddish-violetresidue weighs not more than 1.0 mg (0.010%). powder. Very soluble in water, yielding a bluish-red solutionResidue on ignition (Reagent test): not more than that is strongly fluorescent when dilute. Very soluble in alco-

0.050%, a 2.0-g test specimen being used. Save the resi- hol; slightly soluble in dilute acids and in alkali solutions. Indue. strong acid solution, it forms a pink complex with antimony

Sulfate—Transfer 1 g to a platinum crucible, add 10 mL that is soluble in isopropyl ether.of hot water and 0.5 g of sodium carbonate, evaporate to Clarity of solution—Its solution (1 in 200) is complete anddryness, and ignite, protected from the sulfur in the flame, clear.until the residue is nearly white. Cool, add 20 mL of water Residue on ignition (Reagent test)—Ignite 1 g with 1 mLand 1 mL of 30 percent hydrogen peroxide, boil gently for a of sulfuric acid: the residue weighs not more than 2 mgfew minutes, add 2 mL of hydrochloric acid, and evaporate (0.2%).on a steam bath to dryness. Cool, dissolve the residue in Rhodamine 6G, C28H31C1N2O3—479.02 [989-38-8]—20 mL of water, filter, and to the filtrate add 1 mL of 1 N Use a suitable grade.hydrochloric acid and 3 mL of barium chloride TS: any tur- Ribonuclease Inhibitor—Use a suitable grade.bidity produced within 10 minutes does not exceed that in [NOTE—A suitable grade is available from BD Biosciences,a control containing 0.2 mg of added SO4 and 0.5 mg of www.bdbiosciences.com.]sodium carbonate, 1 mL of 30 percent hydrogen peroxide, Rose Bengal Sodium (Disodium Salt of 4,5,6,7-Tetra-and 2 mL of hydrochloric acid previously evaporated on a chloro-2′,4′,5′,7′-tetraiodofluorescein), C20H2Cl4I4Na2O5—steam bath to dryness (0.02%). 1017.64 [632-69-9]—Fine, rose-colored crystals or crys-

Heavy metals—To the residue retained from the test for talline powder. Soluble in water.[NOTE—Render commerciallyResidue on ignition add 2 mL of hydrochloric acid and available material suitably pure by the following treatment.0.5 mL of nitric acid, and evaporate on a steam bath to Dissolve 8 g in 200 mL of water, and adjust to a pH be-dryness. Dissolve the residue in 30 mL of hot water contain- tween 10 and 11, using short-range pH indicator paper.ing 1 mL of 1 N hydrochloric acid, cool, dilute with water to Add 200 mL of acetone, while stirring gently, then add di-40 mL, and mix. Dilute 20 mL of this solution (retain the lute hydrochloric acid (1 in 10), while continuing to stir,rest of the solution) with water to 25 mL, adjust to a pH until the pH of the solution reaches 4.0. Add 400 mL morebetween 3.0 and 4.0 by the addition of 1 N acetic acid or of water, with stirring, and continue the stirring for 5 min-6 N ammonium hydroxide as necessary, dilute with water to utes. Filter the crystals on a filtering funnel, and return the40 mL, and add 10 mL of freshly prepared hydrogen sulfide crystals to the beaker used for crystallization. RecrystallizeTS: any brown color produced does not exceed that in a three more times in the same manner, and dry the crystalscontrol containing 0.02 mg of added Pb (0.002%). at 110° for 12 hours. Store in an amber bottle in a refrigera-

Iron ⟨241⟩—To 10 mL of the solution retained from the tor at a temperature between 2° and 8°. Prepare this rea-test for Heavy metals add 2 mL of hydrochloric acid, and gent fresh monthly.]

Chromatographic purity—Dissolve 100 mg of rose bengalsodium, prepared as described above, in 100 mL of water,


and apply 10 µL of the solution on suitable chromato- [NOTE—A suitable grade is available as Ottawa Standardgraphic paper. Develop the chromatogram by ascending Sand from Thomas Scientific, 99 High Hill Road at I-295,chromatography, using a mixture of 1 part of dilute alcohol P.O. Box 99, Swedesboro, NJ 08085-0099.](1 in 4) and 1 part of dilute stronger ammonia water (1 in Sand, Washed—It may be prepared as follows. Digest12). Examine the chromatogram in daylight and under UV clean, hard sand at room temperature with a mixture oflight (360 nm): no colored or fluorescent spot is visible 1 part of hydrochloric acid and 2 parts of water (about 13%other than the rose bengal sodium spot. of HCl) for several days, or at an elevated temperature for

[NOTE—A suitable grade is available commercially as “Sil- several hours. Collect the sand on a filter, wash with waterica Gel H.”] until the washings are neutral and show only a slight reac-

Ruthenium Red (Ruthenium Oxychloride, Ammoniated), tion for chloride, and finally dry. Washed sand meets theRu2(OH)2Cl4 · 7NH3 · 3H2O—551.23 [11103-72-3]—A following tests.brownish-red to dark purple powder. Soluble in water. Substances soluble in hydrochloric acid—Digest 10 g with a

S Designations—See supports for gas chromatography mixture of 10 mL of hydrochloric acid and 40 mL of waterunder Reagents, Chromatographic Columns. on a steam bath for 4 hours, replacing from time to time

Saccharose—Use Sucrose (NF monograph). the water lost by evaporation. Filter, and to 25 mL of theSafranin O [477-73-6]—Dark red powder consisting of a filtrate add 5 drops of sulfuric acid, evaporate, and ignite to

mixture of 3,7-diamino-2,8-dimethyl-5-phenylphenazinium constant weight: the residue weighs not more than 8 mgchloride, C20H19ClN4—350.85, and 3,7-diamino-2,8-di- (0.16%).methyl-5-o-tolylphenazinium chloride, C21H21ClN4—364.88— Chloride (Reagent test)—Shake 1 g with 20 mL of waterSparingly soluble in 70 percent alcohol yielding a clear red for 5 minutes, filter, and add to the filtrate 1 mL of nitricsolution with a yellowish-red fluorescence. acid and 1 mL of silver nitrate TS: any turbidity produced

Identification— corresponds to not more than 0.03 mg of Cl (0.003%).A: To 10 mL of a 0.5% w/v solution add 5 mL of hydro- Sawdust, Purified—It may be prepared as follows. Extract

chloric acid: a bluish violet solution is produced. sawdust in a percolator, first with sodium hydroxide solution(1 in 100), and then with dilute hydrochloric acid (1 in 100)B: To 10 mL of a 0.5% w/v solution add 5 mL of so-until the acid percolate gives no test for alkaloid with mer-dium hydroxide solution (1 in 5): a brownish-red precipitatecuric-potassium iodide TS or with iodine TS. Then wash withis produced.water until free from acid and soluble salts, and dry. PurifiedC: To 100 mg add 5 mL of sulfuric acid: a green solu- sawdust meets the following test.tion is produced, which, on dilution, changes to blue and

Alkaloids—To 5 g of purified sawdust contained in a flaskfinally to red.add 50 mL of a mixture of 2 volumes of ether and 1 volumeAbsorption characteristics—Dissolve 50 mg in 250 mL of of chloroform and 10 mL of ammonia TS, and shake fre-50 percent alcohol. Dilute 3 mL of this solution with 50 per- quently for 2 hours. Decant 20 mL of the clear, ether-chloro-cent alcohol to 200 mL. Determine the absorbance, in a form liquid, and evaporate to dryness. Dissolve the residue1-cm cell, with a suitable spectrophotometer. The absorb- in 2 mL of dilute hydrochloric acid (1 in 12), and divide intoance maximum is in the range of 530 to 533 nm; the ratio two portions. To 1 portion add mercuric-potassium iodide(P − 15)/(P + 15) is between 1.10 and 1.32, in which P is TS, and to the other add iodine TS: no turbidity is producedthe wavelength of maximum absorbance. in either portion.[NOTE—A suitable grade is available as catalog number Scandium Oxide, Sc2O3—137.91 [12060-01-1]—Fine,10,214-8 from Sigma-Aldrich, www.sigma-aldrich.com.] white powder.Salicylaldazine, C14H12N2O2—240.26—Use a suitable Secondary Butyl Alcohol—See Butyl Alcohol, Secondary.grade or prepare as follows. Dissolve 300 mg of hydrazine Selenious Acid (Selenous Acid), H2SeO3—128.97sulfate in 5 mL of water, add 1 mL of glacial acetic acid and [7783-00-8]—Colorless or white crystals, efflorescent in dry2 mL of a freshly prepared 1 in 5 solution of salicylaldehyde air and hygroscopic in moist air. Soluble in water and inin isopropyl alcohol, mix, and allow to stand until a yellow alcohol.precipitate is formed. Extract the mixture with two 15-mL

Assay—Accurately weigh about 100 mg, transfer to aportions of methylene chloride. Combine the methyleneglass-stoppered flask, and dissolve in 50 mL of water. Addchloride extracts, and dry over anhydrous sodium sulfate.10 mL of potassium iodide solution (3 in 10) and 5 mL ofDecant the methylene chloride solution, and evaporate it tohydrochloric acid, mix, insert the stopper in the flask, anddryness. Recrystallize the residue of salicylaldazine from aallow to stand for 10 minutes. Dilute with 50 mL of water,mixture of warm toluene and methanol (60:40) with cool-add 3 mL of starch TS, and titrate with 0.1 N sodium thio-ing. Filter, and dry the crystals in vacuum.sulfate VS until the color is no longer diminished, then ti-Melting range ⟨741⟩: between 213° and 219°, but the trate with 0.1 N iodine VS to a blue color. Subtract therange between beginning and end of melting does not ex- volume of 0.1 N iodine solution from the volume of 0.1 Nceed 1°. sodium thiosulfate to give the volume of 0.1 N thiosulfate

Chromatography—Proceed as directed in Limit of hydra- equivalent to selenious acid. Each mL of 0.1 N sodium thio-zine under Povidone: the chromatogram shows only one sulfate is equivalent to 3.225 mg of H2SeO3: not less thanspot. 93% is found.

Salicylaldehyde, (2-Hydroxybenzaldehyde), Insoluble matter—Dissolve 1 g in 5 mL of water: the solu-2-HOC6H4CHO—122.12 [90-02-8]—Clear, colorless to tion is clear and complete.yellowish-green liquid. Specific gravity: about 1.17. SlightlyResidue on ignition (Reagent test): not more thansoluble in water; soluble in alcohol and in ether. May con-

1.0 mg (0.01%), from 10 g.tain a stabilizer.Selenate and sulfate—Dissolve 500 mg in 10 mL of water,Assay—When examined by gas-liquid chromatography,

and add 0.1 mL of hydrochloric acid and 1 mL of bariumusing suitable apparatus and conditions, it shows a purity ofchloride TS: no turbidity or precipitate is formed withinnot less than 98%.10 minutes.Sand, Standard 20- to 30-Mesh—Silica sand, composed

Selenium, Se—At. Wt. 78.96 [7782-49-2]—Dark-redalmost entirely of naturally rounded grains of nearly pureamorphous, or bluish-black, crystalline powder. Soluble inquartz. Predominantly graded to pass an 850-µm (No. 20)solutions of sodium and potassium hydroxides or sulfides;sieve (85 to 100 percentage passing) and be retained on a

600-µm (No. 30) sieve (0 to 5 percentage passing).


insoluble in water. Use a suitable grade with a content of Silica Microspheres—Use a suitable grade.not less than 99.99%. [NOTE—A suitable grade, in a controlled-diameter, spheri-

Selenomethionine, C5H11NO2Se—196.11 cal, porous form, is available commercially as “Zorbax Sil,”[1464-42-2]—[CAUTION—Handle with care, as this reagent is from Agilent, www.agilent.com.]highly toxic.] Siliceous Earth, Chromatographic—

For gas chromatography, use a specially prepared gradeAssay—Weigh accurately about 750 mg, dissolve inmeeting the following general description: Purified siliceous100 mL of methanol, add crystal violet TS, and titrate withearth of suitable mesh size that has been acid- and/or base-0.1 N perchloric acid to a blue-green endpoint. Each mL ofwashed. It may or may not be silanized.0.1 N perchloric acid is equivalent to 19.61 mg of

For column partition chromatography, it is essential thatC5H11NO2Se: between 97.0% and 103.0%, calculated onthe material be free from interfering substances. If such in-the as-is basis, is found.terferences are known or thought to be present, purify theMelting range ⟨741⟩: about 260°, with decomposition. material as follows: Place a pledget of glass wool in the base

Nitrogen content ⟨461⟩—Determine by the Kjeldahl of a chromatographic column having a diameter of 100 mmmethod: between 6.8% and 7.4%, calculated on the as-is or larger, and add Purified Siliceous Earth (NF monograph) tobasis, is found. a height equal to 5 times the diameter of the column. Add

Silica, Calcined Diatomaceous—See Diatomaceous Silica, a volume of hydrochloric acid equivalent to one-third theCalcined. volume of siliceous earth, and allow the acid to percolate

Silica, Chromatographic, Silanized, Flux-Calcined, Acid- into the column. Wash the column with methanol, usingwashed—Use a suitable grade. small volumes at first to rinse the walls of the column, and

[NOTE—Suitable grades are available commercially as “Aer- continue washing with methanol until the last washing isopak 30,” “Diatoport S,” and “Gas-Chrom Z.”] neutral to moistened litmus paper. Extrude the washed col-

Silica Gel—An amorphous, partly hydrated SiO2 occurring umn into shallow dishes, heat on a steam bath to removein glassy granules of varying size. When used as a desiccant, the excess methanol, and dry at 105° until the material isit frequently is coated with a substance that changes color powdery and free from traces of methanol. Store the driedwhen the capacity to absorb water is exhausted. Such material in well-closed containers.colored products may be regenerated (i.e., may regain their [NOTE—A suitable grade is “Chromosorb W-AW.”]capacity to absorb water) by being heated at 110° until the [NOTE—Suitable silanized grades for gas chromatographygel assumes the original color. are “Gas Chrom Q,” and “Chromosorb W (AW- DMCS-

For use as a desiccant, use ACS Silica Gel Desiccant grade. treated).]Silica Gel, Binder-Free—Silica gel for chromatographic [NOTE—A suitable grade for column chromatography is

use formulated without a binder, since only activated forms acid-washed “Celite 545,” available from Sigma-Aldrich,of the silica gel are used as the binding agent. www.sigma-aldrich.com.]

[NOTE—A suitable grade is available commercially as “Sil- Siliceous Earth, Chromatographic, Silanized—Placeica Gel H.”] about 450 g of purified siliceous earth in a large, open, glass

Silica Gel, Chromatographic—Use a suitable grade. crystallizing dish in a vacuum desiccator containing 30 mL[NOTE—A suitable grade is available commercially as “Sil- of a suitable silane, e.g., a mixture of 1 volume of

ica Gel G.”] dimethyldichlorosilane and 1 volume of trimethylchlorosi-Silica Gel, Octadecylsilanized Chromatographic—Use a lane, or a mixture of 1 volume of methyltrichlorosilane and

suitable grade. 2 volumes of dimethyldichlorosilane. Apply vacuum inter-[NOTE—A suitable grade is available commercially as “Re- mittently for several hours, until no liquid silane remains.

versed Phase Uniplates” from Analtech, www.analtech.com.] Float the treated purified siliceous earth on water, and gen-Silica Gel, Porous—Use a grade suitable for high-pressure tly agitate to allow any uncoated particles to sink. Skim the

liquid chromatography. silanized material off the surface, wash it on a sintered-glass[NOTE—A suitable grade for reverse phase high-pressure funnel with warm methanol until the filtrate no longer is

liquid chromatography is available as “LiChrosorb SI60, Re- acidic, and dry at 110°.verse Phase.”] Silicic Acid, SiO2 · xH2O—(anhydrous) 60.08

Silica Gel–Impregnated Glass Microfiber Sheet—Use a [1343-98-2]—White, amorphous powder. Insoluble in watersuitable grade. and in acids; soluble in hot solutions of strong alkalies.

[NOTE—A suitable grade is available commercially as Residue on ignition (Reagent test): not less than 80.0%.“Seprachrom” Chamber with Type SG ITLC, Product No.Nonvolatile with hydrofluoric acid—Heat 500 mg with51923, from Gelman Instrument Co., Ann Arbor, MI

1 mL of sulfuric acid and 10 mL of hydrofluoric acid in a48106.]platinum crucible to dryness, and ignite to constant weight:Silica Gel Mixture, Chromatographic—A mixture of silicathe weight of the residue does not exceed 1.0 mg (0.2%).gel with a suitable fluorescing substance.

[NOTE—A suitable grade is available commercially as “Sil- Chloride (Reagent test)—One g shows not more thanica Gel GF 254.”] 0.05 mg of Cl (0.005%).

Silica Gel Mixture, Chromatographic, with Chemically Sulfate (Reagent test)—Boil 2 g with 20 mL of dilute hy-Bound Amino Groups—Use a suitable grade. drochloric acid (1 in 40), filter, neutralize the filtrate with

Silica Gel Mixture, Dimethylsilanized, Chromato- ammonia TS, and dilute with water to 20.0 mL. A 10-mLgraphic—Use a suitable grade. aliquot of the solution shows not more than 0.1 mg of SO4

[NOTE—A suitable grade is available as “Silica Gel 60 si- (0.01%).lanized RP-2 F254,” from EMD Chemicals, Heavy metals (Reagent test)—Boil 2.5 g with 50 mL of di-www.emdchemicals.com.] lute hydrochloric acid (1 in 10) for 5 minutes, filter whileSilica Gel Mixture, Octadecylsilanized Chromato- hot, and evaporate the filtrate on a steam bath to dryness.graphic—Use a suitable grade. Take up the residue in 20 mL of dilute hydrochloric acid (1[NOTE—A suitable grade is available commercially as KC- in 500), digest for 5 minutes, cool, add water to make18F from Whatman Chemical Separation, Inc., 9 Bridewell 100 mL, and filter. To 40 mL of the filtrate add 10 mL ofPlace, Clifton, NJ 07014.] hydrogen sulfide TS: any color produced is not darker thanSilica Gel Mixture, Octylsilanized, Chromatographic— that produced by adding 10 mL of hydrogen sulfide TS to aUse a mixture of RP-8 chromatographic silica gel with a suit- control containing 0.03 mg of Pb (0.003%).able fluorescing substance agent.

Iron ⟨241⟩—To 20 mL of the filtrate obtained in the testfor Heavy metals add 1 mL of hydrochloric acid, and dilute


with water to 47 mL: the solution shows not more than titrate with 0.02 N hydrochloric acid VS to the disappear-0.015 mg of Fe (0.003%). ance of any pink color: not more than 0.20 mL is required

Silicic Acid—Impregnated Glass Microfilament Sheets (0.016% as NaOH).with Fluorescent Indicator—Use a suitable grade. β-Sitosterol, (22:23 Dihydrostigmasterol), C29H50O—

[NOTE—One example of a suitable grade is “ITLC Type 414.7 [83-46-5]—White powder. Soluble in chloroform.SAF” sheets, available from Gelman Instrument Co., 600 Store in a freezer.South Wagner Rd., Ann Arbor, MI 48106.] Specific rotation ⟨781S⟩: between –33° and –39°, deter-

Silicon Carbide, SiC—40.10 [409-21-2]—In small mined in a solution containing 0.5 g of test specimen perclean chips, suitable for use in promoting ebullition. mL of chloroform.

Silicone (75 Percent Phenyl, Methyl)—Use a suitable Water, Method I ⟨921⟩: not more than 6%.grade. Soda Lime—Use Soda Lime (NF monograph).[NOTE—A suitable grade is available as “OV-25.”] Sodium, Na—At. Wt. 22.98977 [7440-23-5]—UseSilicotungstic Acid, n-Hydrate (Tungstosilicic Acid), ACS reagent grade.H4Si(W3O10)4 · nH2O—2878.17 (anhydrous) Sodium Acetate, NaC2H3O2 · 3H2O—136.08[12520-88-6]—Green powder. [6131-90-4]—Use ACS reagent grade Sodium Acetate Trihy-Assay—Dissolve about 1 g, accurately weighed, in 25 mL drate.

of dilute hydrochloric acid (1 in 5). Add 50 mL of a solution Sodium Acetate, Anhydrous, NaC2H3O2—82.03of 5 g of cinchonine in dilute hydrochloric acid (1 in 2). [127-09-3]—Use ACS reagent grade.Warm on a steam bath for about 30 minutes. Cool, filter Sodium Alizarinsulfonate (Alizarin Red S; Alizarin Sodiumthrough a tared crucible, and ignite at 800° to constant Monosulfonate), C14H7NaO7S · H2O—360.27—Yellow-brownweight. The weight of the residue multiplied by 1.047 is or orange-yellow powder. Freely soluble in water, with pro-equal to the weight of silicotungstic acid dihydrate in the duction of a yellow color; sparingly soluble in alcohol.sample taken. Not less than 98% is found. Sensitiveness—Add 3 drops of a solution of it (1 in 100)Silver Diethyldithiocarbamate, (C2H5)2NCS2Ag—256.14 to 100 mL of water, and add 0.25 mL of 0.02 N sodium[1470-61-7]—Use ACS reagent grade. hydroxide: a red color is produced. Add 0.25 mL of 0.02 NSilver Nitrate, AgNO3—169.87 [7761-88-8]—Use ACS hydrochloric acid: the original yellow color returns.reagent grade. Sodium Ammonium Phosphate (Microcosmic Salt),Silver Oxide, Ag2O—231.74 [20667-12-3]—Brownish- NaNH4HPO4 · 4H2O—209.07—Colorless crystals or whiteblack, heavy powder. Slowly decomposes on exposure to granules. Freely soluble in water; insoluble in alcohol. Efflo-light. Absorbs carbon dioxide when moist. Practically insolu- resces in air and loses ammonia.ble in water; freely soluble in dilute nitric acid and in am-

Insoluble matter and ammonium hydroxide precipitate—monia; insoluble in alcohol. Store in well-closed containers;Dissolve 10 g in 100 mL of water, add 10 mL of ammoniado not expose to ammonia fumes or easily oxidizable sub-TS, and heat on a steam bath for 1 hour. If any precipitatestances.is formed, filter, wash well with water, and ignite: the ig-Assay—Dissolve about 500 mg, previously dried at 120° nited precipitate weighs not more than 1 mg (0.01%).for 3 hours and accurately weighed, in a mixture of 20 mL

Chloride (Reagent test)—One g shows not more thanof water and 5 mL of nitric acid. Dilute with 100 mL of0.02 mg of Cl (0.002%).water, add 2 mL of ferric ammonium sulfate TS, and titrate

Heavy metals—Dissolve 3 g in 25 mL of water, add 15 mLwith 0.1 N ammonium thiocyanate VS to a permanent red-of 1 N sulfuric acid, then add 10 mL of hydrogen sulfide TS:dish-brown color. Each mL of 0.1 N ammonium thiocyanateany brown color developed in 1 minute is not darker thanis equivalent to 11.59 mg of Ag2O: not less than 99.7% ofthat of a control containing 3 mL of Standard Lead SolutionAg2O is found.(see ⟨231⟩) and 0.5 mL of 1 N sulfuric acid (0.001%).Loss on drying—Dry it at 120° for 3 hours: it loses not

Nitrate—Dissolve 1 g in 10 mL of water, add 0.1 mL ofmore than 0.25% of its weight.indigo carmine TS, then add, with stirring, 10 mL of sulfuricNitrate—To 500 mg add 30 mg of sodium carbonate andacid: the blue color persists for 10 minutes (about 0.005%).2 mL of phenoldisulfonic acid TS, mix, and heat on a steam

Sulfate (Reagent test, Method II)—Dissolve 10 g inbath for 15 minutes. Cool, cautiously add 20 mL of water,100 mL of water, add 5 mL of hydrochloric acid, and filter ifrender alkaline with ammonia TS, and dilute with water tonecessary: the filtrate yields not more than 5 mg of residue30 mL: any color produced by the test solution is not darker(0.02%).than that produced in a control containing 0.01 mg of NO3

Sodium Arsenate (Arsenic Acid Sodium Salt), Na2HAsO4 ·(0.002%).7H2O—312.01 [10048-95-0]—Use ACS reagent grade.Substances insoluble in nitric acid—Dissolve 5 g in a mix-

Sodium Arsenite, NaAsO2—129.91 [7784-46-5]—ture of 5 mL of nitric acid and 10 mL of water, dilute withWhite, crystalline powder. Soluble in water; slightly solublewater to about 65 mL, and filter any undissolved residue onin alcohol.a tared filtering crucible (retain the filtrate for the test for

Assay—Transfer about 5.5 g, accurately weighed, to aSubstances not precipitated by hydrochloric acid). Wash the500-mL volumetric flask, dissolve in and dilute with water tocrucible with water until the last washing shows no opales-volume, and mix. Pipet 25 mL of this solution into a suitablecence with 1 drop of hydrochloric acid, and dry at 105° tocontainer, add 50 mL of water and 5 g of dibasic sodiumconstant weight: the residue weighs not more than 1 mgphosphate, swirl to dissolve, and titrate with 0.1 N iodine(0.02%).VS, adding 3 mL of starch TS as the endpoint is approached.Substances not precipitated by hydrochloric acid—DiluteEach mL of 0.1 N iodine is equivalent to 3.746 mg of As.the filtrate obtained in the test for Substances insoluble inBetween 57.0% and 60.5% is found (equivalent to 98.8%nitric acid with water to 250 mL, heat to boiling, and add,to 104.9% of NaAsO2).dropwise, sufficient hydrochloric acid to precipitate all of the

Chloride (Reagent test)—One g shows not more thansilver (about 5 mL), avoiding any great excess. Cool, dilute0.10 mg of Cl (0.01%).with water to 300 mL, and allow to stand overnight. Filter,

evaporate 200 mL of the filtrate in a suitable tared porcelain Heavy metals—Dissolve 200 mg in 8 mL of dilute hydro-dish to dryness, and ignite: the residue weighs not more chloric acid (3 in 8), and evaporate on a steam bath tothan 1.7 mg (0.05%). dryness. Dissolve the residue in 5 mL of dilute hydrochloric

acid (2 in 5), and again evaporate to dryness. Dissolve theAlkalinity—Heat 2 g with 40 mL of water on a steam bathresidue in 10 mL of water, and add 2 mL of diluted aceticfor 15 minutes, cool, and dilute with water to 50 mL. Filter,acid and 10 mL of hydrogen sulfide TS. Any brown colordiscarding the first 10 mL of the filtrate. To 25 mL of the

subsequent filtrate add 2 drops of phenolphthalein TS, and


produced is not darker than that of a control containing Iodine content—Add 10 mL to 5 mL of toluene contained0.01 mg of added Pb (0.005%). in a 125-mL separator fitted with a suitable inert plastic

stopcock, and shake vigorously for 2 min. Extract gentlyIron—Dissolve 1 g in 20 mL of dilute hydrochloric acid (1with three 10-mL portions of dilute phosphoric acid (1 inin 5), and add, dropwise, a slight excess of bromine TS. Boil3), combining the lower phases in a 125-mL iodine flask.the solution to remove the excess bromine, cool, dilute withAdd sodium hypochlorite TS, dropwise, to the combined ex-water to 40 mL, and add 10 mL of ammonium thiocyanatetracts until the solution turns brown, then add 0.5 mL insolution (3 in 10). Any red color produced is not darkerexcess. Shake intermittently for 3 min, add 5 mL of freshlythan that of a control containing 0.02 mg of added Feprepared, saturated phenol solution, mix, and allow to(0.02%).stand for 1 min, accurately timed. Add 1 g of potassiumSulfide—Dissolve 1 g in 20 mL of water, and add 5 drops iodide, shake for 30 s, add 3 mL of starch TS, and titrateof lead acetate TS: no brown color is produced (about with 0.1 N sodium thiosulfate VS: NMT 0.1 mL of 0.1 N0.0005%). sodium thiosulfate is consumed.

Sulfate (Reagent test, Method II)—Dissolve 5 g in 100 mL [NOTE—A suitable grade is available as catalog numberof water, add methyl orange TS, neutralize with 1 N hydro- 277134 from www.sigma-aldrich.com or as catalog numberchloric acid, add 3 mL of the acid in excess, and filter: the 54101 from www.gfschemicals.com.]filtrate yields not more than 3 mg of residue (0.02%). Sodium Biphosphate, NaH2PO4 · H2O—137.99—Use ACS

Sodium Azide, NaN3—65.01 [26628-22-8]—White reagent grade Sodium Phosphate, Monobasic.powder. Sodium Bisulfite [7631-90-5]—This reagent is usually

Assay—[CAUTION—Sodium azide is a potent poison. Its a mixture of sodium bisulfite and sodium metabisulfiteconjugate acid HN3 is more toxic than hydrogen cyanide [7681-57-4]. Use ACS reagent grade Sodium Bisulfite.and is readily liberated from neutral aqueous solutions. Con- Sodium Bitartrate, NaHC4H4O6 · H2O—190.08tact of NaH3 or hydrazoic acid (HN3) with certain metals [6131-98-2]—White crystals or a crystalline powder. Solublemay produce explosive salts. Work in a well-ventilated hood, in cold water.and handle the sample with care.] Dissolve about 100 mg, Assay—Dissolve about 500 mg, accurately weighed, inaccurately weighed, in 50 mL of water, and add 3 drops of 30 mL of water, add phenolphthalein TS, and titrate withphenolphthalein. Adjust the pH, if necessary, to 7.0, and 0.1 N sodium hydroxide VS: each mL of 0.1 N sodium hy-add 35.0 mL of 0.1 N perchloric acid. Pipet, while stirring, droxide is equivalent to 19.01 mg of NaHC4H4O6 · H2O. Be-2.5 mL of 1.0 M sodium nitrite into the solution, and stir for tween 99% and 100.5% is found.15 seconds. Titrate rapidly to the phenolphthalein endpoint Insoluble matter (Reagent test): not more than 1 mg,with 0.1 N sodium hydroxide. The endpoint should be from 10 g (0.01%).reached in less than 4 minutes after addition of perchloric

Chloride (Reagent test)—One g shows not more thanacid because HN3 is readily volatile. Calculate the percent-0.2 mg of Cl (0.02%).age of azide by the formula:

Heavy metals (Reagent test)—Dissolve 4 g in 25 mL of[(NP)(VP) − (NS)(VS)](65.01)(100)/2C water, add 2 drops of phenolphthalein TS, and then add

ammonia TS, dropwise, until the solution is slightly pink.where NP is the normality of perchloric acid solution; VP is Add 4 mL of 1 N hydrochloric acid, dilute with water tothe volume of perchloric acid, in mL, taken; NS is the nor- 40 mL, and add 10 mL of hydrogen sulfide TS: any brownmality of sodium hydroxide solution; VS is the volume, in color produced is not darker than that of a control contain-mL, of sodium hydroxide taken; 65.01 is the molecular ing 0.04 mg of added Pb (0.001%).weight of sodium azide; and C is the weight, in mg, of Sulfate (Reagent test, Method I )—One g shows not moresodium azide. Not less than 98.5% of NaN3 is found. than 0.2 mg of SO4 (0.02%).

Sodium Bicarbonate, NaHCO3—84.01 [144-55-8]— Sodium Borate (Borax; Sodium Tetraborate), Na2B4O7 ·Use ACS reagent grade. 10H2O—381.37 [1303-96-4]—Use ACS reagent grade.

Sodium Biphenyl, C12H9Na—176.19—Available as a solu- [NOTE—Certified Borax is available from the National Insti-tion in 2-ethoxyethyl ether, or in 1,2-dimethoxyethane (di- tute of Standards and Technology, Washington, DC, www.ethylene glycol diether). nist.gov, as standard sample No. 187.]

Activity—Place 20 mL of dry toluene in a titration flask Sodium Borohydride, NaBH4—37.83 [16940-66-2]—equipped with a magnetic stirring bar and a stopper having White, crystalline solid. Freely soluble in water; soluble (witha hole through which the delivery tip of a weight buret may reaction) in methanol. Its solutions are rapidly decomposedbe inserted. Add a quantity of sodium biphenyl sufficient to by boiling.produce a blue color in the mixture, and titrate with amyl Assay—alcohol, contained in a weight buret, to the disappearance

POTASSIUM IODATE SOLUTION (0.25 N)—Dissolve 8.917 g, pre-of the blue color. (Disregard the amounts of sodium bi- viously dried at 110° to constant weight and accuratelyphenyl and amyl alcohol used in this adjustment.) Weigh weighed, in water to make 1000.0 mL.accurately the weight buret containing the amyl alcohol.PROCEDURE—Dissolve about 500 mg, accurately weighed,Transfer the contents of a vial of well-mixed test specimen

in 125 mL of sodium hydroxide solution (1 in 25) in ato the titration flask, and titrate quickly with the amyl alco-250-mL volumetric flask, dilute with the sodium hydroxidehol to the disappearance of the blue color. Weigh the buretsolution to volume, and mix. Pipet 10 mL of the solutionto determine the weight of amyl alcohol consumed, andinto a 250-mL iodine flask, add 35.0 mL of Potassium iodatecalculate the activity, in mEq/vial, by the formula:solution, and mix. Add 2 g of potassium iodide, mix, add10 mL of dilute sulfuric acid (1 in 10), insert the stopper inResult = 11.25Wthe flask, and allow to stand in the dark for 3 minutes. Ti-trate the solution with 0.1 N sodium thiosulfate VS, addingin which W is the weight of amyl alcohol consumed. NLT3 mL of starch TS as the endpoint is approached. Calculate10% activity is found.


the amount, in mg, of NaBH4 in the specimen titrated bythe formula: Sodium Diethyldithiocarbamate, (C2H5)2NCS2Na ·

3H2O—225.31 [20624-25-3]—Use ACS reagent grade.([(35.0)(0.25)] − 0.1V)4.729 Sodium 2,2-dimethyl-2-silapentane-5-sulfonate—See So-

dium 3-(trimethylsilyl)-1-propane sulfonate.in which V is the volume, in mL, of 0.1 N sodium thiosulfate Sodium Dithionite—Use Sodium Hydrosulfite.used in the titration. Not less than 98% is found. Sodium Dodecyl Sulfate (Sodium Lauryl Sulfate),

Sodium Bromide, NaBr—102.89 [7647-15-6]—Use C12H25SO4Na—288.38 [151-21-3]—Light yellow, crystal-ACS reagent grade. line powder.

Sodium Carbonate—Use Sodium Carbonate, Anhydrous. Sodium Ferrocyanide, Na4Fe(CN)6 · 10H2O—484.06Sodium Carbonate, Anhydrous, Na2CO3—105.99 [13601-19-9]—Yellow crystals or granules. Freely soluble in

[497-19-8]—Use ACS reagent grade. water.Sodium Carbonate, Monohydrate, Na2CO3 · H2O— Assay—Dissolve 2 g, accurately weighed, in 400 mL of

124.00 [5968-11-6]—Use ACS reagent grade. water, add 10 mL of sulfuric acid, and titrate with 0.1 NSodium Chloride, NaCl—58.44 [7647-14-5]—Use ACS potassium permanganate VS. Each mL of 0.1 N potassium

reagent grade. permanganate is equivalent to 48.41 mg of Na4Fe(CN)6 ·Sodium Chloride Solution, Isotonic—Use Saline TS. 10H2O. Not less than 98% is found.Sodium Cholate Hydrate (3α,7α,12α-trihydroxy-5β-cho- Insoluble matter (Reagent test): not more than 1 mg,lan-24-oic acid sodium salt; cholalic acid sodium salt), from 10 g (0.01%).C24H39NaO5 · xH2O—430.55 (anhydrous) [206986-87-0]—

Chloride (Reagent test)—Dissolve 1 g in 75 mL of water,It can be from ox or sheep bile. Use a suitable grade with aadd a solution prepared by dissolving 1.2 g of cupric sulfatecontent of not less than 99%.in 25 mL of water, mix, and allow to stand for 15 minutes.Sodium Chromate, Na2CrO4 · 4H2O—234.03To 20 mL of the decanted, clear liquid add 2 mL of nitric[7775-11-3]—Lemon-yellow crystals. Soluble in water.acid and 1 mL of silver nitrate TS: any turbidity producedAssay—Accurately weigh about 300 mg, and dissolve in does not exceed that of a control containing 0.02 mg of Cl,10 mL of water contained in a 500-mL flask. Add 3 g of 2 mL of nitric acid, 1 mL of silver nitrate TS, and sufficientpotassium iodide and 10 mL of diluted sulfuric acid, and cupric sulfate to match the color of the Test solution.dilute with 350 mL of oxygen-free and carbon dioxide-free

Sulfate—Dissolve 5 g in 100 mL of water without heating,water. Titrate the liberated iodine with 0.1 N sodium thio-filter, and to the filtrate add 0.25 mL of glacial acetic acidsulfate VS, adding 3 mL of starch TS as the endpoint is ap-and 5 mL of barium chloride TS: no turbidity is produced inproached. Each mL of 0.1 N sodium thiosulfate consumed is10 minutes (about 0.01% as SO4).equivalent to 7.802 mg of Na2CrO4 · 4H2O. Not less than

Sodium Fluorescein, C20H10Na2O5—376.28—Orange-red,99% is found.hygroscopic powder. Freely soluble in water; slightly solubleInsoluble matter (Reagent test): not more than 1 mg, in alcohol. Its water solution is yellowish red in color andfrom 20 g dissolved in 150 mL of water (0.005%). exhibits a strong yellowish green fluorescence that disap-

Aluminum—Dissolve 20 g in 140 mL of water, filter, and pears when the solution is acidified and reappears when theadd 5 mL of glacial acetic acid to the filtrate. Add stronger solution is neutralized or made basic.ammonia water until alkaline, and digest for 2 hours on a Loss on drying ⟨731⟩—Dry it at 120° to constant weight:steam bath. Pass through hardened filter paper, wash thor- it loses not more than 7.0% of its weight.oughly, ignite, and weigh: the residue weighs not more Sodium Fluoride, NaF—41.99 [7681-49-4]—Use ACSthan 0.8 mg (0.002%). reagent grade.

Calcium—Determine as directed in the test for calcium Sodium Glycocholate, C26H42NNaO6—487.60for ACS reagent grade Potassium Chromate (0.005%). [863-57-0]—White to tan powder. Is hygroscopic. Freely sol-

Chloride—Determine as directed in the test for chloride uble in water and in alcohol.for ACS reagent grade Potassium Chromate (about Specific rotation ⟨781⟩: between +28° and +31°, calcu-0.005%). lated on the dried basis (it is rendered anhydrous by drying

Sulfate—Determine as directed in the test for sulfate for at 100° for 2 hours), determined at 20° in a solution con-ACS reagent grade Potassium Dichromate, but add 4.5 mL taining 10 mg per mL.of hydrochloric acid to the water used to dissolve the test Nitrogen, Method I ⟨461⟩: between 2.6% and 3.2% ofspecimen: the residue weighs not more than 2.4 mg N is found, calculated on the dried basis.(0.01%). Sodium 1-Heptanesulfonate (1-Heptanesulfonic Acid

Sodium Chromotropate—See Chromotropic Acid. Sodium Salt), C7H15NaO3S—202.25 [22767-50-6]—Use aSodium Citrate Dihydrate (2-Hydroxy-1,2,3-propanetri- suitable grade.

carboxylic Acid, Trisodium Salt, Dihydrate), Na3C6H5O7 · Sodium 1-Heptanesulfonate Monohydrate,2H2O—294.10 [6132-04-3]—Use ACS reagent grade. C7H15NaO3S · H2O—220.26 [22767-50-6]—Use a suitable

Sodium Cobaltinitrite, Na3Co(NO2)6—403.94 grade.[13600-98-1]—Use ACS reagent grade. Sodium 1-Hexanesulfonate (1-Hexanesulfonic Acid Sodium

Sodium Cyanide, NaCN—49.01 [1433-33-9]—Use Salt), C6H13NaO3S—188.22 [2832-45-3]—Use a suitableACS reagent grade. grade.

Sodium 1-Decanesulfonate (1-Decanesulfonic Acid Sodium Sodium 1-Hexanesulfonate Monohydrate, Salt), C10H21NaO3S—244.33 [13419-61-9]—Use a suitable C6H13NaO3S · H2O—206.23 [2832-45-3]—Use a suitablegrade for ion pair chromatography with a content of not grade.less than 99.0%. Sodium Hydrogen Sulfate (Sodium Bisulfate), NaHSO4—Sodium Desoxycholate—Use Bile Salts. 120.06 [7681-38-1]—Freely soluble in water; very soluble

Sodium Dichromate, Na2Cr2O7 · 2H2O (for chromic acid in boiling water. It decomposes in alcohol into sodium sul-cleaning mixture)—298.00 [7789-12-0]—Use ACS rea- fate and free sulfuric acid. Use a suitable reagent grade.gent grade. Melting point ⟨741⟩: about 315°.

Sodium Hydrosulfite (Sodium Dithionite), Na2S2O4—174.11 [7775-14-6]—White or grayish-white crystallinepowder. Soluble in water; slightly soluble in alcohol. Gradu-ally oxidizes in air, more readily when in solution, to bisul-fite, acquiring an acid reaction. Is affected by light.


Assay—Accurately weigh about 1 g, dissolve it in a mix- dryness. Take up the residue in 20 mL of water, and filter ifture of 10 mL of formaldehyde TS and 10 mL of water con- necessary. To the filtrate add ammonium hydroxide until thetained in a small glass-stoppered flask, and allow to stand solution is just alkaline, then add 4 drops of ammonium hy-for 30 minutes with frequent agitation. Transfer the solution droxide and 5 mL of ammonium oxalate TS: any turbidityto a 250-mL volumetric flask, add 150 mL of water and produced within 15 minutes does not exceed that in a blank3 drops of methyl orange TS, and then add, dropwise, 1 N containing 0.1 mg of added Ca carried through the entiresulfuric acid to a slightly acid reaction. Dilute with water to procedure (0.001%).250 mL, and mix. To 50.0 mL of the dilution add 2 drops of Phosphate (Reagent test)—Transfer 2 g to a beaker, andphenolphthalein TS and just sufficient 0.1 N sodium hydrox- add 5 mL of hydrochloric acid and 2 g of potassium iodide.ide to produce a slight, pink color, then titrate with 0.1 N Heat the solution for 5 minutes, and cool. Add 2 mL ofiodine, adding 3 mL of starch TS as the indicator. Then dis- 30 percent hydrogen peroxide, and evaporate the solutioncharge the blue color of the solution with 1 drop of 0.1 N to dryness. Rinse the walls of the beaker with a few mL ofsodium thiosulfate, and titrate with 0.1 N sodium hydroxide water, and add 2 mL of hydrochloric acid and 2 mL ofVS to a pink color: each mL of 0.1 N sodium hydroxide is 30 percent hydrogen peroxide. Evaporate again to dryness:equivalent to 3.482 mg of Na2S2O4. Not less than 88% is the residue shows not more than 0.01 mg of PO4 (5 ppm).found. Sodium Iodate, NaIO3—197.9 [7681-55-2]—White to

Sulfide—Add sodium hydroxide solution (1 in 10) to lead yellowish-white powder. Use a suitable reagent grade.acetate TS until the precipitate dissolves. Add 5 drops of this Sodium Lauryl Sulfate—See Sodium Dodecyl Sulfate.solution to a solution of 1 g of the sodium hydrosulfite in Sodium Metabisulfite, Na2S2O5—190.1110 mL of water: no immediate darkening is observed. [7681-57-4]—Use ACS reagent grade.

Sodium Metaperiodate, NaIO4—213.89Heavy metals—Dissolve 1 g in 10 mL of water, add 10 mL[7790-28-5]—Use ACS reagent grade Sodium Periodate.of hydrochloric acid, and evaporate on a steam bath to dry-

Sodium Methoxide, CH3ONa—54.02 [124-41-4]—ness. Dissolve the residue in 20 mL of water and 0.5 mL ofFine, white powder. Reacts violently with water with evolu-diluted hydrochloric acid, filter, and add to the filtratetion of heat. Soluble in alcohol and in methanol.10 mL of hydrogen sulfide TS: no darkening is produced.

Render the solution alkaline with ammonia TS: a slight, Assay—Transfer about 220 mg to a tared, glass-stopperedgreenish color may be produced, but not a dark or white flask, and weigh accurately. Dissolve the test specimen inprecipitate. about 10 mL of methanol, then add 100 mL of water slowly,

with stirring. Add phenolphthalein TS, and titrate with 0.1Suitability for riboflavin assay—To each of 2 or more tubesN hydrochloric acid VS to a colorless endpoint: each mL ofadd 10 mL of water and 1.0 mL of a standard riboflavin so-0.1 N hydrochloric acid VS is equivalent to 5.402 mg oflution containing 20 µg of riboflavin in each mL, and mix.CH3ONa. Not less than 98.0% is found.To each tube add 1.0 mL of glacial acetic acid, mix, add

Sodium Molybdate, Na2MoO4 · 2H2O—241.95with mixing, 0.5 mL of potassium permanganate solution (1[7631-95-0]—Use ACS reagent grade.in 25), and allow to stand for 2 minutes. Then to each tube

Sodium Nitrate, NaNO3—84.99 [7631-99-4]—Useadd, with mixing, 0.5 mL of hydrogen peroxide TS: the per-ACS reagent grade.manganate color is destroyed within 10 seconds. Shake the

Sodium Nitrite, NaNO2—69.00 [7632-00-0]—Use ACStubes vigorously until excess oxygen is expelled. If gas bub-reagent grade.bles remain on the sides of tubes after foaming has ceased,

Sodium Nitroferricyanide (Sodium Nitroprusside), Na2Feremove the bubbles by tipping the tubes so that the solu-(NO)(CN)5 · 2H2O—297.95 [13755-38-9]—Use ACS rea-tion flows slowly from end to end. In a suitable fluorometer,gent grade.measure the fluorescence of the solution. Then add, with

Sodium 1-Octanesulfonate—See Octanesulfonic Acid So-mixing, 8.0 mg of sodium hydrosulfite: the riboflavin isdium Salt.completely reduced in not more than 5 seconds.

Sodium Oxalate, Na2C2O4—134.00 [62-76-0]—UseSodium Hydroxide, NaOH—40.00 [1310-73-2]—UseACS reagent grade.ACS reagent grade.

[NOTE—Sodium Oxalate of a quality suitable as a primarySodium Hypochlorite Solution [7681-52-9]—A solutionstandard is available from the Office of Standard Referenceof sodium hypochlorite (NaOCl) in water. Usually yellow toMaterials, National Institute of Standards and Technology,yellowish-green in color. Has an odor of chlorine. Is affectedWashington, DC, www.nist.gov, as standard sample No.by light and gradually deteriorates. Store it in light-resistant40.]containers, preferably below 25°. [CAUTION—This solution is

Sodium (tri) Pentacyanoamino Ferrate [Trisodiumcorrosive and may evolve gases that are corrosive and toxic.Aminepentacyanoferrate (3-)], Na3[Fe(CN)5NH3]—271.93It is a powerful oxidant that can react violently with reduc-[14099-05-9]—Yellow to tan powder. Soluble in water.ing agents. Is irritating and corrosive to skin and mucous

membranes.] Solubility—Dissolve 500 mg in 50 mL of water, and allowto stand for 1 hour: the solution is clear and free from for-Assay—Transfer about 3 mL to a tared, glass-stopperedeign matter.iodine flask, and weigh accurately. Add 50 mL of water, 2 g

of potassium iodide, and 10 mL of acetic acid, insert the Sensitivity—stopper in the flask, and allow to stand in the dark for 1,1-DIMETHYLHYDRAZINE STANDARD SOLUTION—Place 500 mL of10 minutes. Remove the stopper, rinse the walls of the flask water in a 1-L volumetric flask, and add from a buretwith a few mL of water, and titrate the liberated iodine with 1.27 mL of anhydrous 1,1-dimethylhydrazine. Dilute with0.1 N sodium thiosulfate VS, adding 3 mL of starch TS as water to volume, and mix. Pipet 10 mL of this solution intothe endpoint is neared. Each mL of 0.1 N sodium thiosulfate a 100-mL volumetric flask, and dilute with water to volume.consumed is equivalent to 3.723 mg of NaOCl: not less Each mL of this solution contains the equivalent of 100 µgthan 5.25% is found. If it is desired to calculate the percent- of 1,1-dimethylhydrazine.age of available chlorine, note that each mL of 0.1 N so- BUFFER SOLUTION—Transfer 4.8 g of citric acid monohydratedium thiosulfate consumed is equivalent to 3.545 mg of to a 1-L volumetric flask, dissolve in water, add 14.6 g ofavailable chlorine. sodium phosphate, swirl to dissolve, and dilute with water

Calcium—Transfer 10.0 g to a 150-mL beaker, dissolve in to volume.10 mL of water, and add 5 mL of hydrochloric acid and 2 g TEST PREPARATION—Dissolve 100 mg of sodium (tri)pentacy-of potassium iodide. Heat the mixture for 5 minutes, cool, anoamino ferrate in 100 mL of water.and add 2 mL of 30 percent hydrogen peroxide. Evaporate PROCEDURE—Into each of five 25-mL volumetric flasks pi-to dryness, cool, and add 2 mL of hydrochloric acid and pet 0 mL, 0.25 mL, 0.50 mL, 1.0 mL, and 1.5 mL, respec-2 mL of 30 percent hydrogen peroxide. Rinse the inner walls tively, of 1,1-Dimethylhydrazine standard solution; to eachof the beaker with a few mL of water, and evaporate to


add 15 mL of Buffer solution,and swirl to mix. To each flask, glass electrode and a calomel electrode modified to use 0.1add by pipet 2 mL of Test preparation, mix, dilute with Buffer N tetramethylammonium chloride in methanol as the elec-solution to volume, and allow to stand for 1 hour. Using a trolyte. Perform a blank determination, and make any neces-suitable spectrophotometer, 1-cm cells, and the solution sary correction. Each mL of 0.1 N perchloric acid is equiva-containing no 1,1-Dimethylhydrazine standard solution as the lent to 11.00 mg of CH3COCO2Na: not less than 98.0% isblank, determine the absorbances of the remaining solutions found.at 500 nm. Plot the observed absorbance as the ordinate Solubility—Dissolve 1.5 g in 25 mL of water: the solutionversus the concentration of standard as the abscissa on co- is clear and complete.ordinate paper, and draw the curve of best fit. The plot is Free acid—Dissolve 10 g in 150 mL of water, and titratelinear and the absorbance of the 150-µg solution is not less with 0.5 N sodium hydroxide VS, determining the endpointthan 0.65. potentiometrically: not more than 2.8 mL of 0.5 N sodiumSodium 1-Pentanesulfonate (1-Pentanesulfonic Acid So- hydroxide is consumed (about 1% as C3H4O3).dium Salt), C5H11NaO3S · H2O—192.21 [207605-40-1]— Sodium Salicylate [54-21-7]—It complies with the specifi-Use a suitable grade with a content of NLT 98.0%. cations under Sodium Salicylate (USP monograph), and inSodium 1-Pentanesulfonate, Anhydrous addition meets the requirements of the following test.(1-Pentanesulfonic Acid Sodium Salt, Anhydrous),

Nitrate—Dissolve 100 mg in 5 mL of water, and superim-C5H11SO3Na—174.19 [22767-49-3]—Use a suitable gradepose the solution upon 5 mL of sulfuric acid: no brownish-with a content of NLT 98%.red color appears at the junction of the two liquids.Sodium Perchlorate, NaClO4 · H2O—140.46

Sodium Selenite, Na2SeO3—172.94 [10102-18-8]—[7791-07-3]—Use ACS reagent grade.White, odorless, crystalline powder, usually partially hy-Sodium Peroxide, Na2O2—77.98 [1313-60-6]—Usedrated. Freely soluble in water; insoluble in alcohol.ACS reagent grade.

Assay—Accurately weigh about 180 mg, previously driedSodium Phosphate, Dibasic (Disodium Phosphate; Diso-at 120° to constant weight, and dissolve it in 50 mL ofdium Hydrogen Phosphate; Sodium Phosphate, Dibasic,water in a glass-stoppered flask. Add, successively, 3 g ofHeptahydrate), Na2HPO4 · 7H2O—268.07 [7782-85-6]—potassium iodide and then 5 mL of hydrochloric acid, insertUse ACS reagent grade Sodium Phosphate, Dibasic,the stopper, and allow to stand for 10 minutes. Add 50 mLHeptahydrate.of water, 50.0 mL of 0.1 N sodium thiosulfate VS, and 3 mLSodium Phosphate, Dibasic, Anhydrous (Anhydrous Di-of starch TS, and immediately titrate with 0.1 N iodine VSsodium Hydrogen Phosphate) (for buffer solutions), Na2HPO4—to a blue color. Perform a blank determination. The differ-141.96 [7558-79-4]—Use ACS reagent grade Sodiumence in volumes of 0.1 N iodine is equivalent to 4.323 mgPhosphate, Dibasic, Anhydrous.of Na2SeO3. Between 98% and 101% is found.Sodium Phosphate, Dibasic, Dihydrate (Sodium

Monohydrogen Phosphate; Disodium Hydrogen Phosphate), Solubility—One g in 10 mL of water shows not more thanNa2HPO4 · 2H2O—177.99 [10028-24-7]—Use a suitable a faint haze.grade with a content of not less than 99.5%. [NOTE—A suit- Carbonate—To 500 mg add 1 mL of water and 2 mL ofable grade is available from www.emdchemicals.com, cata- diluted hydrochloric acid: no effervescence is produced.log number SX0713.] Chloride (Reagent test)—A 500-mg portion shows notSodium Phosphate Dibasic, Dodecahydrate (Disodium more than 0.05 mg of Cl (0.01%).Hydrogen Phosphate, Dodecahydrate), Na2HPO4.12H2O—

Nitrate (Reagent test)—A 200-mg portion dissolved in358.14 [10039-32-4]—Use a suitable grade with a con-3 mL of water shows not more than 0.02 mg of NO3tent of between 98.0% and 102.0% of Na2HPO4 · 12H2O.(0.01%).Sodium Phosphate, Dibasic, Heptahydrate (Disodium

Hydrogen Phosphate Heptahydrate; Disodium Phosphate), Selenate and sulfate (as SO4)—To 500 mg in a small evap-Na2HPO4 · 7H2O—268.07 [7782-85-6]—Use ACS reagent orating dish add 20 mg of sodium carbonate and 10 mL ofgrade. hydrochloric acid. Slowly evaporate the solution on a steam

Sodium Phosphate, Monobasic (Sodium Biphosphate; So- bath under a hood to dryness. Wash the sides of the dishdium Dihydrogen Phosphate; Acid Sodium Phosphate; with 5 mL of hydrochloric acid, and again evaporate to dry-Monosodium Orthophosphate), NaH2PO4 · H2O—137.99 ness. Dissolve the residue in a mixture of 15 mL of hot[10049-21-5]—Use ACS reagent grade. water and 1 mL of hydrochloric acid. Proceed as directed

Sodium Phosphate, Monobasic, Anhydrous (Sodium under Sulfate in Reagents (Reagent test, Method I), begin-Biphosphate; Sodium Dihydrogen Phosphate; Acid Sodium ning with “Filter the solution.” The test specimen shows noPhosphate; Monosodium Orthophosphate), NaH2PO4—119.98 more turbidity than that produced by 0.15 mg of SO4

[7558-80-7]—Use a suitable grade with a content of not less (0.03%).than 99.0%. Sodium Sulfate (Glauber’s Salt), Na2SO4 · 10H2O—322.20

Sodium Phosphate, Monobasic, Dihydrate (Sodium [7727-73-3]—Use ACS reagent grade.Dihydrogen Phosphate, Dihydrate), NaH2PO4 · 2H2O—156.01 Sodium Sulfate, Anhydrous, Na2SO4—142.04[13472-35-0]—Use a suitable grade with a content of not [7757-82-6]—Use ACS reagent grade.less than 99.0%. For use in assaying alkaloids by gas–liquid chromatogra-

Sodium Phosphate, Tribasic, Na3PO4 · 12H2O—380.12 phy, it conforms to the following additional test.[10101-89-0]—Use ACS reagent grade. Suitability for alkaloid assays—Transfer about 10 mg of at-

Sodium Phosphite Pentahydrate (Disodium Hydrogen ropine, accurately weighed, to a 25-mL volumetric flask, dis-Phosphite), Na2HPO3 · 5H2O—216.04 [13517-23-2]—Use a solve in and dilute with alcohol to volume. Pipet 3 mL ofsuitable grade with a content of not less than 98%. the solution into each of two 60-mL separators, and add to

[NOTE—A suitable grade is available from Fluka, www. each 10 mL of water, 1 mL of 1 N sodium hydroxide, andsigma-aldrich.com, catalog number 04283.] 10 mL of chloroform. Shake thoroughly, and allow the lay-

Sodium Pyrophosphate, Na4P2O7 · 10H2O—446.06 ers to separate. Filter the organic phase from one separator[13472-36-1]—Use ACS reagent grade. through phase-separating paper, previously washed with

Sodium Pyruvate, CH3COCO2Na—110.04 5 mL of chloroform, supported in a funnel, and collect the[113-24-6]—White to practically white powder or crystalline filtrate in a suitable container. Add 10 mL of chloroform tosolid. Soluble in water. the separator, shake thoroughly, and filter the organic layer

Assay—Transfer about 300 mg, accurately weighed, to a through the same phase-separating paper, collecting andhigh-form titration beaker, add 150 mL of glacial acetic acid, combining the filtrates in the same container. Designate theand stir until dissolved. Titrate with 0.1 N perchloric acid combined filtrates as Solution A. Filter the organic phaseVS, determining the endpoint potentiometrically, using a from the second separator through 30 g of the Anhydrous


Sodium Sulfate, supported on a pledget of glass wool in a Sodium L-Thyroxine—Use Levothyroxine Sodium (USPsmall funnel, and previously washed with chloroform, and monograph).collect the filtrate in a suitable container. Add 10 mL of Sodium 3-(trimethylsilyl)-1-propane sulfonate (Sodiumchloroform to the separator, shake thoroughly, and filter the 2,2-dimethyl-2-silapentane-5-sulfonate), C6H15SiNaO3S—organic layer through the same portion of anhydrous so- 218.32—Use a suitable grade.dium sulfate, collecting and combining the two filtrates in Sodium Tungstate, Na2WO4 · 2H2O—329.85the same container. Designate the combined filtrates as So- [10213-10-2]—Use ACS reagent grade.lution B. Evaporate the two solutions in vacuum to a volume Soluble Starch—See Starch, Soluble.of about 1 mL. Inject an accurately measured volume of So- Solvent Hexane—See Hexane, Solvent.lution A into a suitable gas chromatograph, and record the Sorbitol—Use Sorbitol (NF monograph).peak height. Repeat the determination with a second accu- Stachyose Hydrate, C24H42O21 · xH2O—666.58rately measured volume of Solution A, record the peak [10094-58-3]—Use a suitable grade.height, and obtain the average of the two results. In a simi- Standard Sand, 20- to 30-Mesh—See Sand, Standard 20-lar manner, determine the peak height of two portions of to 30-mesh.Solution B, and obtain the average of the results. The aver- Stannous Chloride, SnCl2 · 2H2O—225.65age value obtained for Solution B is within 5.0% of the value [10025-69-1]—Use ACS reagent grade.obtained for Solution A. Starch, Potato—The starch separated from the tubers of

Under typical conditions, the gas chromatograph contains Solanum tuberosum Linne (Fam. Solanaceae). A more or lessa 4-mm × 1.2-m glass column packed with 3% phase G3 finely granular powder, consisting of starch grains of charac-on packing S1A. After curing and conditioning, the column teristic shape and appearance when examined microscopi-temperature is maintained at 210°, the injector port temper- cally.ature at 225°, and the detector block temperature at 240° Starch, Soluble (for iodimetry) [9005-84-9]—Use ACS re-during the determinations. The carrier gas is helium, flowing agent grade.at a rate of 60 mL per minute. Starch, Soluble, Purified—White, amorphous powder;

Sodium Sulfate Decahydrate—Use Sodium Sulfate. under microscopic examination it shows the characteristicSodium Sulfide, Na2S · 9H2O—240.18 [1313-84-4]— form of potato starch. Soluble in hot water; very slightly

Use ACS reagent grade. soluble in alcohol.Sodium Sulfite—Use Sodium Sulfite, Anhydrous. TEST SOLUTION FOR DETERMINATION OF PH AND SENSITIVITY—StirSodium Sulfite, Anhydrous (Exsiccated Sodium Sulfite), 2.0 g in 10 mL of water, add boiling water to make 100 mL,

Na2SO3—126.04 [7753-83-7]—Use ACS reagent grade. and boil for 2 minutes. The hot solution is almost clear. OnSodium p-Sulfophenylazochromotropate [Trisodium Salt cooling, the solution may become opalescent or turbid, but

of 4,5-Dihydroxy-3-(p-sulfophenylazo)-2, does not gel. Use it as the Test solution.7-naphthalenedisulfonic Acid], C16H9N2Na3O11S3 · 3H2O— pH ⟨791⟩—The pH of the Test solution is between 6.0 and624.47—Bright red powder. Very soluble in water; insoluble 7.5.in alcohol. Combines with zirconium oxychloride to form a

Sensitivity—Mix 2.5 mL of Test solution, 97.5 mL of water,soluble pink zirconium lake.and 0.50 mL of 0.010 N iodine: a distinct blue color results,[NOTE—The reagent is available as Catalog No. 7309 fromand it disappears upon the addition of 0.50 mL of 0.010 NDistillation Products Industries, Eastman Organic Chemicalssodium thiosulfate.Dept., Rochester, NY 14650. A procedure for its preparation

Absorbance—Prepare a pH 5.3 buffer solution by dissolv-is described in Z. Anal. Chem., 146, 417 (1955).]ing 43.5 g of sodium acetate (trihydrate) and 4.5 mL of gla-Sodium Tartrate, Na2C4H4O6 · 2H2O—230.08cial acetic acid in water, transferring the resultant solution[6106-24-7]—Use ACS reagent grade.to a 250-mL volumetric flask, adding water to volume, andSodium Tetraphenylborate, NaB(C6H5)4—342.22mixing.[143-66-8]—Use ACS reagent grade.

Dissolve 1.00 g of Soluble Purified Starch in 2.5 mL of theSodium Tetraphenylboron—See Sodium Tetraphenylbo-buffer solution by warming, transfer to a 100-mL volumetricrate.flask, add water to volume, and mix. Add 0.50 mL of thisSodium Thioglycolate (Sodium Thioglycollate),solution to a 100-mL volumetric flask containing aboutHSCH2COONa—114.10 [367-51-1]—A white, crystalline75 mL of water, 1 mL of 1 N hydrochloric acid, and 1.5 mLpowder. Very soluble in water; slightly soluble in alcohol. Isof 0.020 N iodine, swirling the flask during the addition.hygroscopic, and oxidizes in air. Store in tight, light-resistantAdd water to volume, mix, and allow to stand in the darkcontainers. It should not be used if it is pale yellow orfor 1 hour. The absorbance of this solution, measured atdarker in color.575 nm in a 1-cm cell against a blank, is between 0.5 andAssay—Accurately weigh about 250 mg, and dissolve in0.6.50 mL of oxygen-free water. Add 5 mL of diluted hydrochlo-

Reducing substances—Shake 10.0 g with 100 mL of waterric acid, boil for 2 minutes, cool, and titrate the solutionfor 15 minutes, and allow to settle for about 12 hours. Filterwith 0.1 N iodine VS, adding 3 mL of starch TS toward thea portion of the supernatant through fine sintered glass. Toend: each mL of 0.1 N iodine is equivalent to 11.41 mg of50 mL of the filtrate add 50 mL of alkaline cupric tartrate TS,HSCH2COONa. Not less than 75% is found.and boil for 1 to 2 minutes. Filter the resulting cuprous ox-Insoluble matter—A solution of 1 g in 10 mL of water iside, wash it with hot water and then with alcohol, and dryclear, and practically complete.it at 105° for 2 hours: not more than 47 mg is found, corre-Sulfide—Dissolve 500 mg in 10 mL of water in a small sponding to 0.7% of reducing sugars as maltose.flask, add 2 mL of hydrochloric acid, then place a strip of

Loss on drying ⟨731⟩—Dry it at 105° for 2 hours: it losesfilter paper, moistened with lead acetate TS, over the mouthnot more than 10% of its weight.of the flask, and bring the solution to a boil: the lead ace-

Residue on ignition ⟨281⟩: not more than 0.5%.tate paper is not darkened.Stearic Acid, C18H36O2—284.48 [57-11-4]—Hard,Sodium Thiosulfate, Na2S2O3 · 5H2O—248.19

white crystals or amorphous, white powder. Freely soluble[10102-17-7]—Use ACS reagent grade.in chloroform and in ether; soluble in alcohol and in solventhexane.


Congealing temperature ⟨651⟩: between 67° and 69°. Assay and carbonate—Accurately weigh about 5 g, dis-solve in 200 mL of warm carbon dioxide-free water in aAcid value ⟨401⟩: between 196 and 199.glass-stoppered, 500-mL flask, add phenolphthalein TS, andIodine value ⟨401⟩: not more than 1. titrate with 1 N hydrochloric acid VS to determine the hy-

Saponification value ⟨401⟩: between 197 and 200. droxide alkalinity. Then add methyl orange TS, and titratePalmitic acid—Determine as directed in the Assay under with 1 N hydrochloric acid VS. Each mL of 1 N hydrochloric

Stearic Acid (NF monograph): not more than 5.0% is found. acid required to reach the phenolphthalein endpoint isStearyl Alcohol (1-Octadecanol), C18H38O—270.49 equivalent to 132.9 mg of Sr(OH)2 · 8H2O, and each addi-

[112-92-5]—White flakes, granules, or crystals. Soluble in al- tional mL of 1 N hydrochloric acid VS required to reach thecohol, in ether, in acetone, and in benzene; insoluble in methyl orange endpoint is equivalent to 73.8 mg of SrCO3.water. Not less than 95.0% of Sr(OH)2 · 8H2O and not more than

3.0% of SrCO3 are found.Melting range ⟨741⟩: between 56° and 58°.Chloride (Reagent test)—Dissolve 1.0 g in 100 mL ofOther requirements—It conforms to the tests for Acid

water, and filter if necessary: 1.0 mL of the solution showsvalue, Iodine value, and Hydroxyl value under Stearyl Alcoholnot more than 0.01 mg of Cl (0.1%).(NF monograph).

Stronger Ammonia Water—See Ammonia Water, Calcium (Reagent test)—Stronger. TEST SOLUTION—Dissolve 5.0 g in water, and dilute with

Strontium Acetate, Sr(CH3COO)2 · 1/2H2O—214.72 water to 100 mL.[543-94-2]—White, crystalline powder. Soluble in 3 parts of

SAMPLE SOLUTION—Dilute 10.0 mL of the Test solution withwater; slightly soluble in alcohol. water to 100 mL.Assay—Ignite about 3 g, accurately weighed, in a plati-

CONTROL SOLUTION—To 10.0 mL of the Test solution addnum crucible, protecting from sulfur in the flame. Cool, 0.50 mg of calcium ion (Ca), and dilute with water totransfer the crucible with the residue to a beaker, and add 100 mL.50 mL of water and 40.0 mL of 1 N hydrochloric acid VS.PROCEDURE—Determine the background emission atBoil gently for 30 minutes or longer, if necessary; filter; wash

416.7 nm: the limit is 0.1%.with hot water until the washings are neutral; add methylred TS; and titrate the excess acid with 1 N sodium hydrox- Iron—Dissolve 1 g in warm water, and dilute with wateride VS. Each mL of 1 N hydrochloric acid is equivalent to to 100 mL. To 20 mL of this solution add 2 mL of hydro-107.4 mg of Sr(CH3COO)2 · 1/2H2O: not less than 99% is chloric acid and 0.1 mL of 0.1 N potassium permanganate,found. allow to stand for 5 minutes, and add 3 mL of ammonium

thiocyanate solution (3 in 10). Any red color produced isInsoluble matter (Reagent test): not more than 2 mg,not darker than that of a control containing 0.03 mg offrom 10 g (0.02%).added Fe (0.015%).Free alkali or free acid—Dissolve 3 g in 30 mL of water,

Heavy metals—Dissolve 2.0 g in 14 mL of dilute hydro-and add 3 drops of phenolphthalein TS: no pink color ischloric acid (1 in 6), and evaporate on a steam bath toproduced. Titrate with 0.1 N sodium hydroxide VS to a pinkdryness. Take up the residue in 25 mL of water, filter, andcolor: not more than 0.30 mL of the 0.1 N sodium hydrox-dilute with water to 100 mL (Test solution). To 5.0 mL of theide is required.Test solution add 0.02 mg of lead (Pb), and dilute with waterBarium—Dissolve 1 g in 10 mL of water, and add 1 drop to 30 mL, to provide the standard. For the test specimen,of glacial acetic acid and 5 drops of potassium dichromate use 30 mL of the Test solution. Adjust each solution withsolution (1 in 10): no turbidity is produced within 2 minutes diluted acetic acid or ammonia TS to a pH between 3.0 and(about 0.02%). 4.0 (using short-range pH paper), dilute with water to

Calcium—Ignite 1 g until completely carbonized. Warm 40 mL, and add 10 mL of freshly prepared hydrogen sulfidethe residue with a mixture of 3 mL of nitric acid and 10 mL TS: any brown color developed in the sample solution is notof water, filter, wash with 5 mL of water, and evaporate the darker than that in the control solution (0.004%).filtrate on a steam bath to dryness. Powder the residue, and Strychnine Sulfate, (C21H22N2O2)2 · H2SO4 · 5H2O—856.98dry it at 120° for 3 hours. Reflux the dried powder with [60-41-3]—Colorless or white crystals, or a white, crystalline15 mL of dehydrated alcohol for 10 minutes, cool in ice, powder. Its solutions are levorotatory. One g dissolves inand filter. Repeat the extraction with 10 mL of dehydrated about 35 parts of water, in 85 mL of alcohol, and in aboutalcohol. Evaporate the combined filtrates to dryness, add 220 mL of chloroform. Insoluble in ether.0.5 mL of sulfuric acid, and ignite: the weight of the residue Solubility—A solution of 500 mg in 25 mL of water isis not more than 10 mg (0.3% of Ca). complete, clear, and colorless.

Chloride (Reagent test)—One g shows not more than Residue on ignition (Reagent test): not more than0.1 mg of Cl (0.01%). 0.1%.Heavy metals (Reagent test): 0.001%. Brucine—To 100 mg add 1 mL of dilute nitric acid (1 inIron ⟨241⟩—Dissolve 1.0 g in 45 mL of water, and add 2): a yellow color may be observed, but not a red or red-

2 mL of hydrochloric acid: the solution shows not more dish-brown color.than 0.01 mg of Fe (0.001%). Styrene-Divinylbenzene Anion-exchange Resin, 50- to

Alkali salts—Dissolve 2 g in 80 mL of water, heat to boil- 100-Mesh—See Anion-exchange Resin, 50- to 100-Mesh, Sty-ing, add an excess of ammonium carbonate TS, boil for rene-Divinylbenzene.5 minutes, dilute with water to 100 mL, and filter. Evaporate Styrene-Divinylbenzene Cation-exchange Resin,50 mL of the filtrate, and ignite: the residue, after correcting Strongly Acidic—See Cation-exchange Resin, Styrene-for the ignition residue from half the volume of the clear Divinylbenzene, Strongly Acidic.ammonium carbonate TS used above, is not more than Styrene-Divinylbenzene Copolymer Beads—Neutral, po-3 mg (0.3%). rous, cross-linked beads, 200–400 mesh, molecular weight

operating range up to 2,000 (based on beads fully swollenNitrate—Dissolve 1 g in 10 mL of water, add 0.10 mL ofin benzene). Suitable for use in the gel permeation separa-indigo carmine TS, and then add 10 mL of sulfuric acid: thetion of lipophilic polymers and other solutes requiring or-blue color persists for 5 minutes (about 0.01% of NO3).ganic eluant.Strontium Hydroxide (Strontium Hydroxide Octahydrate),

Sr(OH)2 · 8H2O—265.76 [18480-07-4]—White, crystalline,free-flowing powder. Sparingly soluble in water. May absorbcarbon dioxide from the air. Keep tightly closed.


[NOTE—A suitable grade is available commercially as “Bi- cence does not exceed that of quinine sulfate solution (1 inoBeads S-X” from Bio-Rad, www.bio-rad.com.] 1,600,000,000), similarly measured.

Succinic Acid, C4H6O4—118.09 [771-50-6]—Use ACS Sulfuric Acid, Fuming, H2SO4 plus free SO3

reagent grade. [8014-95-7]—having a nominal content of 15%, 20%, orSudan III, C22H16N4O—352.39 [85-86-9]—Red to red- 30% of free SO3—Use ACS reagent grade (containing be-

brown powder. Use a suitable grade. tween 15.0% and 18.0%, between 20.0% and 23.0%, orbetween 30.0% and 33.0% of free SO3).Assay—When tested by thin-layer chromatography (see

Sulfuric Acid, Nitrogen Free, H2SO4—98.08Chromatography ⟨621⟩) with the use of plates coated with[7664-93-9]—Use a suitable grade. chromatographic silica gel mixture and a developing system

[NOTE—A suitable grade is available as Sulfuric Acid, Ultrexconsisting of a mixture of hexane and ethyl acetate (80:20),II, catalog number 6902-05 from www.mallbaker.com.]and examined under short-wavelength UV light, a single

Sulfurous Acid, H2SO3—82.08 [7782-99-2]—A waterspot is exhibited, with trace impurities.solution of sulfur dioxide. Use ACS reagent grade.Sudan IV, C24H20N4O—380.44 [85-83-6]—Brown to

Sunflower Oil [8001-21-6]—Use a suitable grade.reddish-brown powder.Supports for Gas Chromatography—See supports forAssay—Transfer about 25 mg, accurately weighed, to a gas chromatography in the Chromatographic Reagents sec-100-mL volumetric flask. Dissolve in chloroform, dilute with tion under Chromatography ⟨621⟩.chloroform to volume, and mix. Dilute 2.0 mL of the result- Tannic Acid (Tannin) [1401-55-4]—Use ACS reagenting solution with chloroform to 50.0 mL. Determine the ab- grade.sorbance of this solution in 1-cm cells at the wavelength of Tartaric Acid, H2C4H4O6—150.09—Use ACS reagentmaximum absorbance at about 520 nm, with a suitable grade.spectrophotometer, using chloroform as the blank. Calculate Tertiary Butyl Alcohol—See Butyl Alcohol, Tertiary.the percentage of Sudan IV in the test specimen taken by Testosterone Benzoate, C26H32O2—376.53—Use a suita-the formula: ble grade.2′,4′,5′,7′-Tetrabromofluorescein (Eosin Y, Eosin Yellowish,(100A)/(85C)

Eosin Bromo ES, Solvent Red 43, Acid Red 87), C20H8Br4O5—167.8 [630-20-6]—Dark red to brown powder. Solubilityin which A is the absorbance at 520 nm and C is the con-0.1% in water (clear orange solution). Use a suitable grade.centration of the test specimen in g per L. Not less than

Tetrabromophenolphthalein Ethyl Ester, C22H14Br4O4—90% is found.661.96—Use ACS reagent grade.Loss on drying ⟨731⟩—Dry it at 105° for 2 hours: it loses Tetrabutylammonium Bromide, (C4H9)4NBr—322.37not more than 10% of its weight. [1643-19-2]—Use ACS reagent grade.Sulfamerazine (4-Amino-N-(4-methyl-2-pyrimidinyl)- Tetrabutylammonium Hydrogen Sulfate, C16H37NO4S—benzenesulfonamide), C11H12N4O2S—264.30 [127-79-7]— 339.54 [32503-27-8]—White, crystalline powder. SolubleUse a suitable grade with a content of NLT 99.0%. in alcohol yielding a slightly hazy, colorless solution.Sulfamic Acid, HSO3NH2—97.09 [5329-14-6]—Use

Assay—Dissolve about 170 mg, accurately weighed, inACS reagent grade.40 mL of water. Titrate with 0.1 N sodium hydroxide VS,Sulfanilamide, C6H8N2O2S—172.21 [63-74-1]—Usedetermining the endpoint potentiometrically. Perform aUSP Sulfanilamide Melting Point RS.blank determination and make any necessary correction.Sulfanilic Acid, p-NH2C6H4SO3H · H2O—191.21Each mL of 0.1 N sodium hydroxide is equivalent to[121-57-3]—Use ACS reagent grade.33.95 mg of C16H37NO4S. Not less than 97.0% is found.Sulfatase Enzyme Preparation—Use a suitable grade.

Melting range ⟨741⟩: between 169° and 173°.[NOTE—A suitable grade is available commercially underTetrabutylammonium Hydrogen Sulfate Ion Pairing Re-catalog number S-9626 from Sigma-Aldrich, Web site: www.

agent—A mixture of tetrabutylammonium hydrogen sulfatesigma-aldrich.com.]and phosphate buffer. Use a suitable grade.Sulfathiazole Sodium (4-Amino-N-2-thiazolylbenzenesul-

[NOTE—A suitable grade is available as catalog numberfonamide Sodium Salt), C9H8N3NaO2S2—277.29WAT084189 from the Waters Corporation (www.waters.[144-74-1]—Use a suitable grade.com).]Sulfonic Acid Cation-exchange Resin—See Cation-ex-

0.4 M Aqueous Tetrabutylammonium Hydroxide,change Resin, Sulfonic Acid.C16H37NO—259.47 [2052-49-5]—Use a suitable grade. Sulfosalicylic Acid, C6H3(COOH)(OH)(SO3H)-1,2,5 ·

[NOTE—A suitable grade is available as catalog number2H2O—254.22 [97-05-2]—Use ACS reagent grade.420120025 from www.fishersci.com.]Sulfur—Use Precipitated Sulfur (USP monograph).

Tetrabutylammonium Hydroxide, 1.0 M in MethanolSulfur Dioxide Detector Tube—A fuse-sealed glass tube[2052-49-5]—Use a suitable grade.so designed that gas may be passed through it and contain-

Tetrabutylammonium Hydroxide 30-Hydrate, ing suitable absorbing filters and support media for an io-C16H37NO · 30H2O—799.93 [2052-49-5]—Use a suitabledine-starch indicator.grade with a content of not less than 98.0%.Measuring range: 1 to 25 ppm.

Tetrabutylammonium Hydroxide, 40 Percent in Water,[NOTE—Available from Draeger Safety, Inc., www.draeger.[CH3(CH2)3]4NOH—259.47 [2052-49-5]—Use a suitablecom, or from Gastec Corp., www.gastec.co.jp, distributed ingrade.the USA by www.nextteq.com.]

Tetrabutylammonium Iodide, (C4H9)4NI—369.37Sulfuric Acid, H2SO4—98.08 [7664-93-9]—Use ACS re-[311-28-4]—White, shiny, crystalline flakes. Soluble in alco-agent grade.hol and in ether; slightly soluble in water.Sulfuric Acid, Diluted (10 percent)—Cautiously add

Assay—Dissolve 370 mg, accurately weighed, in 60 mL of57 mL of sulfuric acid to about 100 mL of water, cool toacetone with vigorous stirring. Stir the solution by mechani-room temperature, and dilute with water to 1000 mL.cal means, add 10 mL of 16% sulfuric acid, and titrate withSulfuric Acid, Fluorometric—Use ACS reagent grade Sul-0.1 N silver nitrate VS, determining the endpoint potentio-furic Acid that conforms to the following additional test:metrically, using a glass–silver electrode system, and addingFluorescence—Using a suitable fluorometer having a sharpthe titrant in 0.1-mL increments as the endpoint is ap-cut-off 360-nm excitation filter and a sharp cut-off 415-nmproached. Perform a blank determination, and make anyexcitation filter, determine the fluorescence of the sulfuricnecessary corrections. Each mL of 0.1 N silver nitrate isacid in a cuvette previously rinsed with water followed by

several portions of the acid under examination: the fluores-


equivalent to 36.94 mg of (C4H9)4NI: not less than 99.0% is Boiling range (Reagent test): between 177° and 187°,found. at a pressure of 9 mm of Hg.

Tetrabutylammonium Phosphate, (C4H9)4NH2PO4— Tetraethylenepentamine, C8H23N5—189.31339.46 [5574-97-0]—White to off-white powder. Soluble [112-57-2]—Colorless liquid.in water. Assay—Inject an appropriate volume into a gas chromat-

Assay—Dissolve about 1.5 g, accurately weighed, in ograph (see Chromatography ⟨621⟩) equipped with a flame-100 mL of water. Without delay, titrate with 0.5 N sodium ionization detector, helium being used as the carrier gas.hydroxide VS, determining the endpoint potentiometrically. The following conditions have been found suitable: a 0.25-Perform a blank determination, and make any necessary mm × 30-m capillary column coated with a 1-µm layer ofcorrection. Each mL of 0.5 N sodium hydroxide is equiva- phase G2; the injection port temperature is maintained atlent to 169.7 mg of (C4H9)4NH2PO4. Not less than 97.0% is 250°; the detector temperature is maintained at 300°; andfound. the column temperature is maintained at 150° and pro-

2,3,7,8-Tetrachlorodibenzo-p-dioxin, 13C-labeled, grammed to rise 10° per minute to 280°. The area of the13C12H4Cl4O2—333.84—Clear, colorless liquid. C8H23N5 peak is not less than 30% of the total peak area.

Assay—Inject an appropriate volume into a gas chromat- Refractive index ⟨831⟩: between 1.503 and 1.507 atograph (see Chromatography ⟨621⟩) equipped with an elec- 20°.tron-capture detector, helium being used as the carrier gas. Tetraheptylammonium Bromide, (C7H15)4NBr—490.70The following conditions have been found suitable: a 0.25- [4368-51-8]—White, flaky powder.mm × 30-m capillary column coated with a 1-µm layer of Melting range ⟨741⟩: between 89° and 91°.phase G2; the injection port temperature is maintained at Tetrahexylammonium Hydrogen Sulfate, C24H53NO4S—300°; the detector temperature is maintained at 300°; and 451.75 [32503-34-7]—Use a suitable grade with a con-the column temperature is maintained at 70° and pro- tent of not less than 98.0%.grammed to rise 15° per minute to 300°. The area of the Delta-8-tetrahydrocannabinol (∆-13C12H4Cl4O2 peak is not less than 99.0% of the total peak 8-Tetrahydrocannabinol), C21H30O2—314.47 [5957-75-5]—area. Use a suitable grade which may be a solid material or a

[NOTE—A suitable grade is available from Cambridge Iso- solution in methanol.[NOTE—A suitable grade of a methano-topes Laboratories (www.isotope.com).] lic solution (1 mg/mL) is available from www.cerilliant.com,

2,3,7,8-Tetrachlorodibenzofuran, 13C-labeled, catalog number T-032.]13C12H4Cl4O—317.84—Clear, colorless liquid. Tetrahydrofuran, C4H8O—72.11 [109-99-9]—Use ACS

Assay—Inject an appropriate volume into a gas chromat- reagent grade.ograph (see Chromatography ⟨621⟩) equipped with an elec- Tetrahydrofuran, Peroxide-Free, C4H8O—72.11—Usetron-capture detector, helium being used as the carrier gas. ACS reagent grade.The following conditions have been found suitable: a 0.32- Peroxide—Transfer 8 mL of potassium iodide and starchmm × 60-m capillary column coated with a 1-µm layer of TS to a 12-mL ground glass-stoppered cylinder aboutphase G27; the injection port temperature is maintained at 15 mm in diameter. Fill completely with the substance300°; the detector temperature is maintained at 350°; and under test, mix, and allow to stand protected from light forthe column temperature is maintained at 70° and pro- 5 minutes. No color develops.grammed to rise 15° per minute to 275°. The area of the Tetrahydrofuran, Stabilizer-Free—Use a suitable grade.13C12H4Cl4O peak is not less than 99.0% of the total peak Tetrahydro-2-furancarboxylic Acid (±Tetrahydro-2-furoicarea. Acid), C5H8O3—116.12 [16874-33-2]—Use a suitable

[NOTE—A suitable grade is available from Cambridge Iso- grade with a content of not less than 97%. [NOTE—A suita-topes Laboratories (www.isotope.com).] ble grade is available from www.sigma-aldrich.com, catalog

1,1,2,2-Tetrachloroethane, C2H2Cl4—167.8 number 341517.][630-20-6]—Colorless clear liquid. Specific gravity: 1.553. N-(2-Tetrahydrofuroyl)piperazine (1-[(Tetrahydro-Refractive index at 20° is 1.481. Use a suitable grade. 2-furanyl)carbonyl]piperazine), C9H16N2O2—184.23—Use a

Tetracosane, C24H50—338.66 [646-31-1]—White pow- suitable grade.der. [NOTE—A suitable grade can be obtained from EMS-

Melting range ⟨741⟩: between 51° and 53°. DOTTIKON, www.ems-dottikon.ch.]Tetradecane, C14H30—198.39 [629-59-4]—Clear, col- 1,2,3,4-Tetrahydronaphthalene, C10H12—132.21

orless liquid. [119-64-2]—Colorless liquid.Assay—When examined by gas-liquid chromatography, it Refractive index ⟨831⟩: 1.5401 at 20°.

shows a purity of not less than 98%. The following condi- Tetramethylammonium Bromide, (CH3)4NBr—154.05tions have been found suitable for assaying the reagent: a [64-20-0]—Use ACS reagent grade.3-mm × 2.4-m stainless steel column packed with phase Tetramethylammonium Chloride, (CH3)4NCl—109.60G16 on support S1; the carrier gas is helium, flowing at a [75-57-0]—Colorless crystals. Soluble in water and in alco-rate of 27.5 mL per minute; the column temperature is hol; insoluble in chloroform.maintained at 250°, the injection port is maintained at Assay—Transfer about 200 mg, accurately weighed, to a200°, and the detector is maintained at 280°. A flame-ioni- beaker, add 50 mL of water and 10 mL of diluted nitric acid,zation detector is employed. swirl to dissolve the test specimen, add 50.0 mL of 0.1 N

Melting range, Class II ⟨741⟩: between 4° and 8°, within silver nitrate VS, and mix. Add 2 mL of ferric ammoniuma 2° range. sulfate TS and 5 mL of nitrobenzene, shake, and titrate the

excess silver nitrate with 0.1 N ammonium thiocyanate VS:Refractive index ⟨831⟩: between 1.4280 and 1.4300 ateach mL of 0.1 N silver nitrate is equivalent to 10.96 mg of20°.(CH3)4NCl. Not less than 98% is found.Tetraethylammonium Perchlorate, (C2H5)4NClO4—

Tetramethylammonium Hydroxide, (CH3)4NOH—91.15229.70—White crystals. Soluble in water. Use a suitable[75-59-2]—Available as an approximately 10% or approxi-grade.mately 25% aqueous solution, or as the crystalline pentahy-Tetraethylene Glycol, C8H18O5—194.23 [112-60-7]—drate. Is clear and colorless. Tetramethylammonium hydrox-Nearly colorless liquid. Refractive index: about 1.46.ide is a stronger base than ammonia and rapidly absorbsAssay—When examined by gas–liquid chromatography, carbon dioxide from the air. Store in tight containers.using suitable gas chromatographic apparatus and condi-

Assay—Accurately weigh a glass-stoppered flask contain-tions, it shows a purity of not less than 90%.ing about 15 mL of water. Add a quantity of a solution oftetramethylammonium hydroxide, equivalent to about


200 mg of (CH3)4NOH, and again weigh. Add methyl red acid. Heat to 60° and maintain this temperature while titrat-TS, and titrate the solution with 0.1 N hydrochloric acid VS: ing with 0.1 N ceric sulfate VS, determining the endpointeach mL of 0.1 N hydrochloric acid is equivalent to potentiometrically, using silver-silver chloride and platinum9.115 mg of (CH3)4NOH. electrodes. Each mL of 0.1 N ceric sulfate is equivalent to

11.99 mg of TlCl. Not less than 99% is found.Residue on evaporation—Evaporate 5 mL of solution on aTheobromine, C7H8N4O2—180.17 [83-67-0]—White,steam bath, and dry at 105° for 1 hour: the weight of the

crystalline solid. Very slightly soluble in water and in alcohol;residue is equivalent to not more than 0.02% of the weightalmost insoluble in benzene, in ether, and in chloroform.of the test specimen.

Assay—Dissolve about 34 mg, accurately weighed, inAmmonia and other amines—Accurately weigh a quantity50 mL of glacial acetic acid. Titrate with 0.1 N perchloricof solution, corresponding to about 300 mg of (CH3)4NOH,acid VS, determining the endpoint potentiometrically. Per-in a low-form weighing bottle tared with 5 mL of water.form a blank determination, and make any necessary correc-Add a slight excess of 1 N hydrochloric acid (about 4 mL),tion. Each mL of 0.1 N perchloric acid is equivalent toevaporate on a steam bath to dryness, and dry at 105° for18.02 mg of C7H8N4O2. Not less than 95% is found.2 hours: the weight of the tetramethylammonium chloride

Thiazole Yellow (CI Direct Yellow 9; Clayton Yellow; Titanso obtained, multiplied by 0.8317, represents the quantity,Yellow), C28H19N5Na2O6S4—695.74 [1829-00-1]—Yellow-in mg, of (CH3)4NOH in the portion of test specimen takenish-brown powder. Soluble in water and in alcohol to yieldand corresponds to within 0.2% above or below that foundin each instance a yellow solution; soluble in dilute alkali toin the Assay.yield a brownish-red solution. Protect from light.Tetramethylammonium Hydroxide, Pentahydrate,

(CH3)4NOH · 5H2O—181.23 [10424-65-4]—White to off- Solubility—A 200-mg portion mixed with 50 mL of waterwhite crystals. Is hygroscopic. Strong base. Keep well-closed. shows not more than a faint haze.Soluble in water and in methanol. Residue on ignition—Accurately weigh about 1.5 g, previ-

Assay—Accurately weigh about 800 mg, dissolve in ously dried at 105° for 2 hours, and ignite until thoroughly100 mL of water, and titrate with 0.1 N hydrochloric acid charred. Cool, add 2 mL of nitric acid and 2 mL of sulfuricVS, determining the endpoint potentiometrically. Perform a acid, ignite gently to expel excess acids, then at 600° toblank determination, and make any necessary correction. 800° to constant weight: the residue of sodium sulfateEach mL of 0.1 N hydrochloric acid is equivalent to (Na2SO4) is between 19.8% and 21.5% of the weight of the18.22 mg of (CH3)4NOH · 5H2O: not less than 98% is found. test specimen (theory is 20.4%).

Tetramethylammonium Hydroxide Solution in Metha- Sensitiveness to magnesium—Add 0.2 mL of a solution (1nol [75-59-2]—A solution in methanol of tetramethylammo- in 10,000) and 2 mL of 1 N sodium hydroxide to a mixturenium hydroxide [(CH3)4NOH—91.15]. Is generally available of 9.5 mL of water and 0.5 mL of a solution prepared byin concentrations of 10% and 25%. The following specifica- dissolving 1.014 g of clear crystals of magnesium sulfate intions apply specifically to the 25% concentration; for other water, diluting with water to 100 mL, then diluting 10 mLconcentrations, appropriate adjustments in the procedures of the resulting solution with water to 1 L: a distinct pinkmay be necessary. color is produced within 10 minutes.

Assay—Accurately weigh about 1 g of the solution, and Thioacetamide, C2H5NS—75.13 [62-55-5]— Use ACSdilute with water to about 50 mL. Add phenolphthalein TS, reagent grade.and titrate with 0.1 N hydrochloric acid VS to the disap- 2-Thiobarbituric Acid, C4H4N2O2S—144.15pearance of the pink color: each mL of 0.1 N hydrochloric [504-17-6]—White leaflets. Slightly soluble in water.acid VS is equivalent to 91.15 mg of (CH3)4NOH. Between Melting temperature ⟨741⟩: 236°, with decomposition.23% and 25% is found. 2,2′-Thiodiethanol, (HOCH2CH2)2S—122.19

Clarity—A portion of it in a test tube is clear, or only [111-48-8]—Pale yellow to colorless liquid.slightly turbid, when viewed transversely. Assay—Not less than 98% of C4H10O2S is found, a suita-

Tetramethylammonium Nitrate, (CH3)4NNO3—136.15 ble gas chromatograph equipped with a flame-ionization[1941-24-8]—White crystals. Freely soluble in water. detector being used. The following conditions have been

Tetramethylbenzidine, (4-(4-Amino-3,5-dimethylphenyl)- found suitable: a 4.0-mm × 1.83-m glass column is packed2,6-dimethylaniline; 3,3′,5,5′ Tetramethylbenzidine; 3,3′5,5′- with 10% phase G25 on support S1A; the column, injectionTetramethyl-[1,1′-biphenyl] 4,4′-diamine) C16H20N2—240.34 port, and detector temperatures are maintained at 200°,[54827-17-7]—Use a suitable grade. 250°, and 310°, respectively.

4,4′-Tetramethyldiaminodiphenylmethane [(4,4′- Refractive index ⟨831⟩: between 1.4250 and 1.4270,Methylenebis(N,N-dimethylaniline)], [(CH3)2NC6H4]2CH2— at 20°.254.38 [101-61-1]—Off-white crystals. Thioglycolic Acid, HSCH2COOH—92.12 [68-11-1]—AMelting range ⟨741⟩: between 87° and 90°. colorless or nearly colorless liquid. Miscible with water. Solu-

Tetramethylsilane, (CH3)4Si—88.23 [75-76-3]—Use ble in alcohol.ACS reagent grade. Sensitiveness—Mix 1 mL with 2 mL of stronger ammoniaTetrapropylammonium Chloride, C12H28ClN—221.82 water, and dilute with water to 20 mL. Add 1 mL of this[5810-42-4]—Use a suitable grade with a content of not less solution to a mixture of 20 mL of water and 0.1 mL of dilutethan 98.0%. ferric chloride TS (1 in 100), then add 5 mL of ammonia TS:Tetrasodium Ethylenediaminetetraacetate a distinct pink color is produced.((Ethylenedinitrilo)tetraacetic Acid Tetrasodium Salt), Thionine Acetate, C12H9N3S · C2H4O2—287.34C10H12N2Na4O8—380.17—Fine, white, crystalline powder. [78338-22-4]—Use a suitable grade.Soluble in water. Thiourea, (NH2)2CS—76.12 [62-56-6]—Use ACS rea-

Loss on drying ⟨731⟩—Dry it at 105° for 4 hours: it loses gent grade.not more than 8% of its weight. Thorium Nitrate, Th(NO3)4 · 4H2O—552.12

Thallous Chloride, TlCl—239.84—Fine, white, crystalline [13823-29-5]—Use ACS reagent grade.powder. Soluble in about 260 parts of cold water and in Thrombin Human (Factor IIa )— ~33,600about 70 parts of boiling water; insoluble in alcohol. Poison- [9002-04-4]—A preparation of a serine protease (enzyme)ous; use with adequate ventilation. that converts human fibrinogen into fibrin. It is obtained

Assay—Dissolve about 500 mg, accurately weighed, in a from human plasma and may be prepared by precipitationmixture of 80 mL of water and 0.5 mL of sulfuric acid. with suitable salts and organic solvents under controlledWhen dissolution is complete, add 20 mL of hydrochloric


conditions of pH, ionic strength, and temperature. A yellow- o-Tolidine (4,4′-Diamino-3,3′-dimethylbiphenyl), (NH2)ish-white powder, freely soluble in a 9 g per L solution of (CH3)C6H3 · C6H3(CH3)(NH2)4,3,3′,4′—212.29sodium chloride, which forms a cloudy, pale yellow solution. [119-93-7]—White to reddish crystals or crystalline powder.Store in a sealed, sterile container under nitrogen, protected Slightly soluble in water; soluble in alcohol, in ether, and infrom light, at a temperature below 0°. One unit corresponds dilute acids. Preserve in well-closed containers, protectedto the amount of enzyme that hydrolyzes 1 µmol of Tos- from light. [CAUTION—Avoid contact with o-tolidine and mix-Gly-Pro-Arg-4-nitroaniline acetate per minute at a pH of 8.4 tures containing o-tolidine, and conduct all tests in a well-ven-and a temperature of 37°. tilated fume hood.]

Thromboplastin [9035-58-9]—Buff-colored powder, or Melting range ⟨741⟩: between 129° and 131°.opalescent or turbid suspension. It exhibits thrombokinase Tolualdehyde (o-Tolualdehyde), C8H8O—120.15activity derived from the acetone-extracted brain and/or [529-20-4]—Use a suitable grade.lung tissue of freshly killed rabbits. It may contain sodium p-Tolualdehyde, C8H8O—120.15 [104-87-0]—Color-chloride and calcium chloride in suitable proportions, and it less to yellow, clear liquid.may contain a suitable antimicrobial agent. It is used in sus- Assay—When examined by gas-liquid chromatography, itpension form for the determination of the prothrombin time shows a purity of not less than 98%. The following condi-and activity of blood. Its thrombokinase activity is such that tions have been found suitable for assaying the article: Ait gives a clotting time of 11 to 16 seconds with normal 3-mm × 1.8-m stainless steel column packed with a 5%human plasma and the proper concentration of calcium phase G4 on support S1. Nitrogen, having a flow rate ofions. Store in tight containers, preferably at a temperature about 12 mL per minute, is the carrier gas, the detector andbelow 5°. column temperature are about 125°, and the injection port

Loss on drying ⟨731⟩—[NOTE—This test is applicable only temperature is about 205°. A flame-ionization detector isto the dry form.] Dry it in vacuum at 60° for 6 hours: it employed and the specimen is a 5% solution in carbon di-loses not more than 5.0% of its weight. sulfide.

Thymidine, C10H14N2O5—242.2 [50-89-5]—White Refractive index ⟨831⟩: between 1.544 and 1.546, atpowder. Use a suitable grade. 20°.Thymol, C6H3[CH3][OH][CH(CH3)2]1,3,4—150.22 Toluene (Toluol), C6H5CH3—92.14 [108-88-3]—Use[89-83-8]—Colorless, often large, crystals, or a white, crys- ACS reagent grade.talline powder. Is affected by light. Has greater density than p-Toluenesulfonic Acid, CH3C6H4SO3H · H2O—190.22water, but when liquefied by fusion is less dense than water. [6192-52-5]—Use ACS reagent grade.Its alcohol solutions are neutral to litmus. One g dissolves in p-Toluenesulfonyl-L-arginine Methyl Ester Hydrochlo-about 1000 mL of water, in 1 mL of alcohol, in 1 mL of ride (Nα-p-Tosyl-L-arginine methyl ester hydrochloride; TAME),chloroform, in 1.5 mL of ether, and in about 2 mL of olive C14H22N4O4S · HCl—378.88 [1784-03-8]—Determine itsoil. Soluble in glacial acetic acid and in fixed or volatile oils. suitability as directed in the test for Trypsin under Chymo-Store in tight, light-resistant containers. trypsin (USP monograph).Melting range ⟨741⟩: between 48° and 51°, but when p-Toluic Acid, CH3C6H4COOH—136.15 [99-94-5]—

melted it remains liquid at a considerably lower tempera- White, crystalline powder. Sparingly soluble in hot water;ture. very soluble in alcohol, in methanol, and in ether.

Nonvolatile matter—Volatilize 2 g on a steam bath, and Assay—Transfer about 650 mg, accurately weighed, to adry at 105° to constant weight: the residue weighs not suitable container, dissolve in 125 mL of alcohol, add 25 mLmore than 1 mg (0.05%). of water, and mix. Titrate with 0.5 N sodium hydroxide VS,

Thyroglobulin, [9010-34-8]—A protein having a molecu- determining the endpoint potentiometrically. Perform alar weight of 670 kDa. Available as a slightly beige, freeze- blank determination, and make any necessary correction.dried powder made from bovine or porcine thyroid gland. Each mL of 0.5 N sodium hydroxide is equivalent toUse a suitable grade. 68.07 mg of C8H8O2: not less than 98% is found.

Tin, Sn—At. Wt. 118.71 [7440-31-5]—Use ACS rea- Melting range ⟨741⟩: over a range of 2° that includesgent grade. 181°.Titanium Tetrachloride, TiCl4—189.68 [7550-45-0]— o-Toluidine (2-Aminotoluene; 2-Methylaniline),Clear, colorless liquid. Fumes in air. [CAUTION—It reacts vio- C6H4(CH3)(NH2)1,2—107.15 [95-53-4]—Light yellow liq-lently with water.] uid becoming reddish brown on exposure to air and light.Assay—Accurately weigh 0.75 g into 100 mL of 2 N sulfu- Soluble in alcohol, in ether, and in dilute acids; slightly solu-

ric acid contained in a Smith weighing buret. Pour the soluble in water. Preserve in well-closed containers, protectedtion through a zinc–mercury reduction column into 50 mL from light.of 0.1 N ferric ammonium sulfate VS. Elute with 100 mL of Specific gravity ⟨841⟩: 1.008 at 20°.2 N sulfuric acid and 100 mL of water. Add 10 mL of phos-

Boiling range (Reagent test): between 200° and 202°.phoric acid, and titrate with 0.1 N potassium permanganatep-Toluidine, C7H9N—107.15 [106-49-0]—White toVS. Perform a blank determination, and make any necessary

beige crystals or flakes.correction. Each mL of 0.1 N potassium permanganate isFreely soluble in alcohol, in acetone, in methanol, and inequivalent to 18.97 mg of TiCl4. Not less than 99.5% is

dilute acids; slightly soluble in water.found.Assay—Dissolve 400 mg, accurately weighed, in 100 mLBoiling range (Reagent test): between 135° and 140°.

of glacial acetic acid, and titrate with 0.1 N perchloric acidTitanium Trichloride (Titanous Chloride), TiCl3—154.23VS, determining the endpoint potentiometrically. Perform a[7705-07-9]—Black, hygroscopic powder, unstable in air.blank determination, and make any necessary correction.Soluble in water, the solution depositing titanic acid on ex-Each mL of 0.1 N perchloric acid is equivalent to 10.72 mgposure to air. Is available usually as 15% to 20%, dark vio-of CH3C6H4NH2. Not less than 98%, calculated on the driedlet-blue, aqueous solutions. Store the solution in tightlybasis, is found.closed, glass-stoppered bottles, protected from light.


Loss on drying—Weigh accurately about 1 g, and dry at Melting range ⟨741⟩: between 47° and 49°.30° to constant weight: it loses not more than 2% of its Suitability—Determine its suitability for use in the test forweight. Related compounds under Propoxyphene Hydrochloride (USP

Toluidine Blue, (C15H16ClN3S)2 · ZnCl2—747.95 monograph) as follows. Dissolve a suitable quantity in chlo-[6586-04-5]—Use a suitable grade. roform to yield a solution containing 20 µg per mL. Follow-

Toluidine Blue O, C15H16N3SCl—305.8 [92-31-9]—Use ing the directions given in the test for Related compoundsa suitable grade. under Propoxyphene Hydrochloride, inject a suitable volume

n-Triacontane, C30H62—422.81 [638-68-6]—Use a suit- of the solution into the chromatograph, and record theable grade. chromatogram. Concomitantly record the chromatogram

2,4,6-Triamino-5-nitrosopyrimidine, C4H6N6O—154.13— from the Standard preparation prepared as directed in thePink powder. test for Related compounds: only one main peak is obtained

Assay—Dissolve about 34 mg, accurately weighed, in from the n-tricosane solution, and no minor peaks are ob-50 mL of glacial acetic acid. Titrate with 0.1 N perchloric served at, or near, the peak positions obtained for propoxy-acid VS, determining the endpoint potentiometrically. Per- phene, acetoxy, or carbinol in the chromatogram from theform a blank determination, and make any necessary correc- Standard preparation.tions. Each mL of 0.1 N perchloric acid is equivalent to Triethanolamine—Use Trolamine (NF monograph).15.41 mg of C4H6N6O. Not less than 97% is found. Triethylamine, (C2H5)3N—101.19 [121-44-8]—Color-

Tributyl Phosphate (Tri-n-butyl Phosphate), (C4H9)3PO4— less liquid. Slightly soluble in water. Miscible with alcohol,266.31 [126-73-8]—Clear, almost colorless liquid. Slightly with ether, and with cold water. Store in well-closed con-soluble in water. Miscible with common organic solvents. tainers. Use a suitable grade with a content of not less thanSpecific gravity: about 0.976. 99.5%.

Triethylamine Hydrochloride, C6H15N · HCl—137.65Refractive index ⟨831⟩: between 1.4205 and 1.4225.[554-68-7]—White to off-white powder.Tributylethylammonium Hydroxide, C14H33NO—

231.42—Use a suitable grade. Assay—Transfer about 35 mg, accurately weighed, to aTributyrin (Glyceryl Tributyrate), C15H26O6—302.36 suitable beaker, add 50 mL of glacial acetic acid, and dis-

[60-01-5]—Colorless, oily liquid. Insoluble in water; very sol- solve by stirring. Add 5 mL of mercuric acetate TS, with stir-uble in alcohol and in ether. ring. When solution is complete, titrate with 0.1 N perchlo-

ric acid VS, determining the endpoint potentiometrically.Assay—Inject an appropriate specimen into a suitable gasPerform a blank titration, and make any necessary correc-chromatograph (see Chromatography ⟨621⟩) equipped withtion. Each mL of 0.1 N perchloric acid is equivalent toa flame-ionization detector, nitrogen being used as the car-13.77 mg of C6H15N · HCl. Not less than 97.5% of C6H15N ·rier gas. The following conditions have been found suitable:HCl is found.a 3-mm × 1.8-m stainless steel column containing phase G4

on support S1A; the injection port temperature is main- Melting point ⟨741⟩: between 256° and 259°, with de-tained at 270°; and the detector temperature is maintained composition.at 300°. The area of the tributyrin peak is not less than 98% Triethylamine Phosphate (Triethylammonium Phosphate),of the total peak area. C6H15N · H3O4P—199.19—Use a suitable grade.

[NOTE—A suitable grade is available from www.Refractive index ⟨831⟩: between 1.4345 and 1.4365 attciamerica.com, catalog number T1300.]20°.

Triethylene Glycol, C6H14O4—150.17 [112-27-6]—Col-Acid content—Transfer 1.0 g, accurately weighed, to a orless to pale yellow liquid. Is hygroscopic. Miscible withbeaker, add 75 mL of methanol, and dissolve by stirring. water, with alcohol, and with toluene.When dissolution is complete, add 25 mL of water, and ti-Assay—Inject an appropriate test specimen into a suitabletrate with 0.05 N potassium hydroxide VS, using phenol-

gas chromatograph equipped with a flame-ionization detec-phthalein TS as the indicator. Perform a blank determina-tor (see Chromatography ⟨621⟩), helium being used as thetion, and make any necessary correction. Each mL of 0.05 Ncarrier gas. The following conditions have been found suita-potassium hydroxide is equivalent to 88.1 mg of butyricble: a 3-mm × 1.85-m stainless steel column packed withacid: not more than 0.5% is found.support S2; the injection port, column, and detector tem-Trichloroacetic Acid, CCl3COOH—163.39 [76-03-9]—peratures are maintained at 250°, 230°, and 310°, respec-Use ACS reagent grade.tively. The area of the C6H14O4 peak is not less than 97% ofTrichloroethane—See Methyl Chloroform.the total peak area.Trichlorofluoromethane, CCl3F—137.37 [75-69-4]—

Colorless liquid. Refractive index ⟨831⟩: between 1.4550 and 1.4570, at20°.Assay—Inject an appropriate specimen into a gas chro-

Triethylenediamine (1,4-Diazobicyclo[2.2.2]octane),matograph (see Chromatography ⟨621⟩) equipped with aC6H12N2—112.17 [280-57-9]—Use a suitable grade with athermal conductivity detector, helium being used as the car-content of not less than 98%.rier gas. The following conditions have been found suitable:

Trifluoroacetic Acid, C2HF3O2—114.02 [76-05-1]—a 2.0-mm × 1.8-m glass column packed with 10% G1 phaseColorless liquid. Miscible with ether, with acetone, with eth-on support S1A; the injection port temperature is main-anol, with benzene, with carbon tetrachloride, and withtained at 50°; the detector temperature is maintained athexane.300°; and the column temperature is maintained at 0° and

programmed to rise 3° per minute to 50°. The area of the Assay—Dissolve about 300 mg, accurately weighed, inCCl3F peak is not less than 99% of the total peak area. 25 mL of water and 25 mL of alcohol. Titrate with 0.1 N

sodium hydroxide VS, determining the endpoint potentio-Refractive index ⟨831⟩: between 1.380 and 1.384 atmetrically. Perform a blank determination, and make any20°.necessary corrections. Each mL of 0.1 N sodium hydroxideTrichlorotrifluoroethane—Use a suitable grade.is equivalent to 11.40 mg of C2HF3O2. Not less than 99% is[NOTE—A suitable preparation, listed as “Freon-TF aerosol,found.” is available from E. I. du Pont de Nemours and Co., Wil-

Trifluoroacetic Anhydride, (F3CCO)2O—210.03mington, DE 19898.][407-25-0]—Colorless liquid. Boils between 40° and 42°. Ex-n-Tricosane, C23H48—324.63 [638-67-5]—Colorless ortremely volatile. Avoid exposure to air or water.white, more or less translucent mass, showing a crystalline

structure. Has a slightly greasy feel. Insoluble in water and Assay—Transfer about 0.8 g, accurately weighed, to ain alcohol; soluble in chloroform, in ether, in volatile oils, glass-stoppered flask containing 50 mL of methanol. Addand in most warm fixed oils; slightly soluble in dehydrated 500 mg of phenolphthalein, and titrate with 0.1 N sodiumalcohol. Boils at about 380°.


methoxide VS to a pink endpoint. Calculate A by the Residue on ignition (Reagent test)—Ignite 1 g with 0.5 mLformula: of sulfuric acid: the residue weighs not more than 10 mg

(1%).V/W Trimethylchlorosilane—See Chlorotrimethylsilane.

2,2,4-Trimethylpentane (Isooctane), C8H18—114.23in which V is the volume, in mL, of 0.1 N sodium methox- [540-84-1]—Use ACS reagent grade.ide and W is the weight, in mg, of test specimen. To a 2,4,6-Trimethylpyridine (5-Collidine), C8H11N—121.18second glass-stoppered flask containing 50 mL of a mixture [108-75-8]—Clear, colorless liquid. Soluble in cold waterof dimethylformamide and water (1:1) transfer 0.4 g, accu- and less soluble in hot water; soluble in alcohol, in chloro-rately weighed, of the specimen under test, add 500 mg of form, and in methanol. Miscible with ether.phenolphthalein, and titrate with 0.1 N sodium hydroxide Assay—Inject an appropriate test specimen into a suitableVS to a pink endpoint. Calculate B by the formula: gas chromatograph (see Chromatography ⟨621⟩), helium be-

ing used as a carrier gas. The following conditions haveV1/W1been found suitable: a 3-mm × 1.85-m stainless steel col-umn containing phase G16 on support S1A; the injectionin which V1 is the volume, in mL, of 0.1 N sodium hydrox- port, column, and detector temperatures are maintained atide and W1 is the weight, in mg, of test specimen. Calculate 180°, 165°, and 270°, respectively; and a flame-ionizationthe percentage of (F3CCO)2O by the formula: detector is used. The area of the C8H11N peak is not lessthan 98% of the total peak area.2100.3(B − A)

Refractive index ⟨831⟩: between 1.4970 and 1.4990, at20°.Not less than 97% is found. If 2A is greater than B, calculate

N-(Trimethylsilyl)-imidazole, C6H12N2Si—140.26the percentage of F3CCOOH by the formula:[18156-74-6]—A clear, colorless, to light yellow liquid.

1140.3(2A − B) Refractive index ⟨831⟩: between 1.4744 and 1.4764 at20°.

α,α,α-Trifluoro-p-cresol (4-hydroxybenzotrifluoride, Trimethyltin Bromide, C3H9BrSn—243.724-trifluoromethylphenol), C7H5F3O—162.11 [402-45-9] [1066-44-0]—Use a suitable grade.

2,4,6-Trinitrobenzenesulfonic Acid, C6H2(NO2)3SO3H ·Melting range ⟨741⟩: between 48° and 52°.3H2O—347.21 [2508-19-2]—Pale yellow to tan crystals.2,2,2-Trifluoroethanol, CF3CH2OH—100.04Use a suitable grade. Also available as a 5% (w/v) or a 1 M[75-89-8]—Colorless liquid.aqueous solution.Assay—Inject an appropriate specimen into a gas chro-

Trinitrophenol—See Picric Acid.matograph (see Chromatography ⟨621⟩) equipped with aTrioctylphosphine Oxide, C24H51PO—386.63flame-ionization detector, helium being used as the carrier

[78-50-2]—White, crystalline powder. Insoluble in water; sol-gas. The following conditions have been found suitable: auble in organic solvents.0.25-mm × 30-m capillary column coated with a 1-µm layer

Melting range ⟨741⟩: between 54° and 56°.of phase G2; the injection port temperature is maintained at1,3,5-Triphenylbenzene, (C6H5)3C6H3—306.41100°; the detector temperature is maintained at 150°; and

[612-71-5]—White to off-white powder.the column temperature is maintained at 0° and pro-grammed to rise 10° per minute to 150°. The area of the Melting range ⟨741⟩: between 172° and 175°.CF3CH2OH peak is not less than 99% of the total peak area. Triphenylmethane, C19H16—244.34 [519-73-3]—Light

brown powder.Boiling range: between 77° and 80°.2,2,2-Trifluoroethyldifluoromethyl Ether (Difluoromethyl- Assay—Inject an appropriate volume into a gas chromat-

2,2,2-trifluoroethyl ether), C3H3F5O—150.05—Clear liquid. ograph (see Chromatography ⟨621⟩) equipped with a flame-Use a suitable grade. ionization detector, helium being used as the carrier gas.

The following conditions have been found suitable: a 0.25-Boiling range: between 28° and 30°.mm × 30-m capillary column coated with a 1-µm layer of[NOTE—A suitable grade is available from PCR Incorpo-phase G2; the injection port temperature is maintained atrated, P.O. Box 1466, Gainesville, FL 32602. Tel:300°; the detector temperature is maintained at 300°; and904-376-8246. The catalogue number is 17151-2.]the column temperature is maintained at 200° and pro-(m-Trifluoromethylphenyl) Trimethylammoniumgrammed to rise 10° per minute to 300°. The area of theHydroxide in Methanol—Use a suitable grade.C19H16 peak is not less than 99% of the total peak area.[NOTE—A suitable grade is available as “Meth-Prep II”

from Alltech, www.alltechweb.com.] Melting range ⟨741⟩: between 92° and 94°.5-(Trifluoromethyl)uracil, C5H3F3N2O2—180.08 Triphenylmethanol, C19H16O—260.34 [76-84-6]—

[54-20-6]—White to off-white powder. White to off-white powder.Assay—When tested by thin-layer chromatography, with Assay—Inject an appropriate volume into a gas chromat-

the use of plates coated with chromatographic silica gel ograph (see Chromatography ⟨621⟩) equipped with a flame-mixture, a developing system consisting of chloroform, ionization detector, helium being used as the carrier gas.methanol, and acetic acid (17:2:1), and examined visually The following conditions have been found suitable: a 0.25-and under long-wavelength UV light, a single spot is exhib- mm × 30-m capillary column coated with a 1-µm layer ofited. phase G2; the injection port temperature is maintained at

Trifluorovinyl Chloride Polymer (Fluorolube; 1-Chloro-1,2, 280°; the detector temperature is maintained at 300°; and2-trifluoro-ethene Homopolymer), (C2ClF3)x—Use a suitable the column temperature is maintained at 180°. The area ofgrade. the C19H16O peak is not less than 96.5% of the total peak

[NOTE—A suitable grade is available as catalog number area.Z123552 from www.sigma-aldrich.com.] Triphenyltetrazolium Chloride, C19H15ClN4—334.80

Trimethylacethydrazide Ammonium Chloride (Betaine [298-96-4]—White to yellowish, crystalline powder. SolubleHydrazide Chloride; Girard Reagent T), in about 10 parts of water and of alcohol; slightly soluble in[(CH3)3N+CH2CONHNH2]Cl–—167.64 [123-46-6]—Color- acetone; insoluble in ether. Usually contains solvent of crys-less or white crystals. Freely soluble in water. One g dis- tallization, and when dried at 105° it melts at about 240°,solves in about 25 mL of alcohol. Insoluble in chloroform with decomposition.and in ether. Hygroscopic. Solubility—Separate 100-mg portions dissolve completely

Melting range ⟨741⟩: between 185° and 192°, deter- in 10 mL of water and in 10 mL of alcohol, respectively, tomined after recrystallization from hot alcohol, if necessary. yield solutions that are clear, or practically so.


Loss on drying ⟨731⟩—Dry it at 105° to constant weight: fate TS, and add to the combined filtrate 0.5 mL of sodiumit loses not more than 5.0% of its weight. nitrite solution (1 in 20): no red color is produced within

15 minutes.Residue on ignition (Reagent test): negligible, fromTuberculin, Purified Protein Derivative (Tuberculin100 mg.

PPD)—Derived from the human strain of Mycobacterium tu-Sensitiveness—Dissolve 10 mg in 10 mL of dehydrated al- berculosis, and available either as a solution or as a lyophi-cohol (A). Then dissolve 10 mg of dextrose in 20 mL of de- lized powder. For lyophilized powder, reconstitute accordinghydrated alcohol (B). To 0.2 mL of B add 1 mL of dehy- to the manufacturer’s instructions using the diluent pro-drated alcohol and 0.5 mL of dilute tetramethylammonium vided by the manufacturer. Solutions may contain a stabi-hydroxide TS (1 volume diluted with 9 volumes of dehy- lizer and a preservative. One Tuberculin Unit (TU) is equiva-drated alcohol), then add 0.2 mL of A: a pronounced red lent to 0.02 µg of Tuberculin PPD.color develops within about 10 minutes. Tubocurarine Chloride (7′,12′-Dihydroxy-6,6′-dimethoxy-Tris(2-aminoethyl)amine, C6H18N4—146.23 2,2′,2′-trimethyltubocuraranium Chloride), C37H42Cl2N2O6—[4097-89-6]—Yellow liquid. Soluble in methanol. 681.65 [6989-98-6]—Use a suitable grade with an assayAssay—Dissolve about 80 mg in 30 mL of methanol. Add result between 98.0% and 102.0%.

40 mL of water, and titrate with 1 N hydrochloric acid, de- [NOTE—A suitable grade is available from Acros Organics,termining the endpoint potentiometrically. Perform a blank catalog number 24349 at www.acros.com.]determination, and make any necessary correction. Each mL Tungstic Acid, H2WO4—249.85 [7783-03-1]—Use aof 1 N hydrochloric acid is equivalent to 48.75 mg of suitable grade with a content of not less than 99%.C6H18N4. Not less than 98.0% is found. L-Tyrosine Disodium, C9H9NO3Na2—225.2

Refractive index ⟨831⟩: between 1.4956 and 1.4986 at [69849-45-6]—Off-white to tan powder. Use a suitable20°. grade.

Tris(hydroxymethyl)aminomethane [77-86-1]—Use ACS Uracil, C4H4N2O2—112.09 [66-22-8]—White to cream-reagent grade—See also Tromethamine. colored, crystalline powder. Melts above 300°. One g dis-

Tris(hydroxymethyl)aminomethane Acetate, C4H11O3 · solves in about 500 mL of water; less soluble in alcohol; sol-NCH3—181.19 [6850-28-8]—White powder with lumps. uble in ammonia TS and in sodium hydroxide TS. Its solu-Use a suitable grade. tions yield no precipitate with the usual alkaloidal

Tris(hydroxymethyl)aminomethane Hydrochloride, precipitants.C4H11NO3 · HCl—157.60 [1185-53-1]—Colorless crystals. Residue on ignition (Reagent test): negligible, fromUse a suitable grade. 100 mg.

N-Tris(hydroxymethyl)methylglycine, C6H13NO5—179.2 Loss on drying ⟨731⟩—Dry it at 105° for 2 hours: it loses[5704-04-1]—White, crystalline powder. Use a suitable not more than 2% of its weight.grade. Uranyl Acetate (Uranium Acetate), UO2(C2H3O2)2 · 2H2O—Tritirachium Album Proteinase K—Use a suitable grade. 424.15 [541-09-3]—Use ACS reagent grade.[NOTE—A suitable grade can be obtained from Qiagen, Urea, NH2CONH2—60.06 [57-13-6]—Use ACS reagentInc., www.qiagen.com.] grade.Tromethamine [Tris(hydroxymethyl)aminomethane; THAM; Urethane (Ethyl carbamate), C3H7NO2—89.092-Amino-2-(hydroxymethyl)-1,3-propanediol], C4H11NO3— [51-79-6]—White powder with chunks. Freely soluble in121.14—Use ACS reagent grade Tris(hydroxymethyl)amino- water.methane.Melting range ⟨741⟩: between 48° and 50°.Tropaeolin OO (Acid Orange 5), C18H14N3NaO3S—375.38

Uridine, C9H12N2O6—244.20 [58-96-8]—White pow-[554-73-4]—Orange-yellow scales, or yellow powder. Solu-der.ble in water.

Assay—pH range: from 1.4 (red) to 2.6 (yellow).Tropic Acid, C9H10O3—166.18 [529-64-6]—Use a suit- MOBILE PHASE—Prepare a mixture of methanol and 0.2 M

able grade. ammonium acetate (10:90), and adjust with phosphoricTropine, C8H15NO—141.2 [120-29-6]—Use a suitable acid to a pH of 7.0.

grade. TEST SOLUTION: 0.5 mg per mL in water.Trypan Blue (Direct Blue 14), C34H24N6Na4O14S4—960.8 PROCEDURE—Inject about 20 µL of the Test solution into a[72-57-1]—Use a suitable grade. liquid chromatograph (see Chromatography ⟨621⟩), equippedTryptone—Use Pancreatic Digest of Casein. with a 280-nm detector and a 4.6-mm × 15-cm columnL-Tryptophane, C11H12N2O2—204.23 [73-22-3]—White that contains packing L1. The flow rate is about 2.0 mL peror not more than slightly yellow leaflets or powder. One g minute. The area of the C9H12N2O6 peak is not less thandissolves in about 100 mL of water; soluble in dilute acids 99% of the total peak area.and in solutions of the alkali hydroxides; slightly soluble in

Melting range ⟨741⟩: between 166° and 171°.alcohol.Valeric Acid, C5H10O2—102.13 [109-52-4]—Clear, col-Assay—Accurately weigh about 300 mg, dissolve in a orless liquid.mixture of 3 mL of formic acid and 50 mL of glacial aceticAssay—Accurately weigh about 500 mg, transfer to aacid, add 2 drops of crystal violet TS, and titrate with 0.1 N

suitable container, add 30 mL of water, and mix. Add 40 mLperchloric acid VS to a green endpoint. Each mL of 0.1 Nof water, and mix. Add phenolphthalein TS, and titrate withperchloric acid is equivalent to 20.42 mg of C11H12N2O2. Be-0.1 N sodium hydroxide VS. Each mL of 0.1 N sodium hy-tween 98.0% and 102.0%, calculated on the dried basis, isdroxide is equivalent to 10.21 mg of C5H10O2: not less thanfound.99.0% of C5H10O2 is found.Specific rotation ⟨781⟩: between −30.0° and −33.0°, deter- Valerophenone, C11H14O—162.23 [1009-14-9]—Col-mined in a solution containing 1.0 g of test specimen, previ- orless liquid.ously dried at 105° for 3 hours, in 100 mL.

Assay—Inject an appropriate specimen into a suitable gasLoss on drying ⟨731⟩—Dry it at 105° for 3 hours: it loses chromatograph (see Chromatography ⟨621⟩) equipped withnot more than 0.3% of its weight. a flame-ionization detector, helium being used as the carrierResidue on ignition (Reagent test): not more than gas. The following conditions have been found suitable: a

0.1%. capillary column coated with a 1-µm layer of phase G2; theTyrosine—Dissolve 100 mg in 3 mL of diluted sulfuric injection port temperature is maintained at 250°; the detec-

acid, add 10 mL of mercuric sulfate TS, and heat on a steam tor temperature is maintained at 300°; and the column tem-bath for 10 minutes. Filter, wash with 5 mL of mercuric sul- perature is maintained at 150° and programmed to rise 10°


per minute to 300°. The area of the C11H14O peak is not less CH3COOCH=CH2 peak is not less than 99% of the totalthan 98% of the total peak area. peak area.

2-Vinylpyridine, C7H7N—105.14 [100-69-6].Refractive index ⟨831⟩: 1.5149 at 20°.Boiling range: between 79° and 82°, at 29 mm of mer-Boiling range: between 105° and 107°, at a pressure of

cury.5 mm of mercury.Vanadium Pentoxide, V2O5—181.88 [1314-62-1]— Density: 0.975 at 25°.

Fine, yellow to orange-yellow powder. Slightly soluble in Refractive index ⟨831⟩: about 1.5490 at 20°.water; soluble in concentrated acids and in alkalies; insolu- Vinylpyrrolidinone (1-Vinyl-2-pyrrolidinone; 1-Vinyl-ble in alcohol. 2-pyrrolidone; N-Vinylpyrrolidinone; N-Vinylpyrrolidone),

Assay—Transfer about 400 mg, accurately weighed, to a C6H9NO—111.14 [88-12-4]—Colorless liquid.500-mL conical flask, and add 150 mL of water and 30 mL Assay—Inject an appropriate volume into a gas chromat-of dilute sulfuric acid (1 in 2). Boil the solution on a hot ograph (see Chromatography ⟨621⟩) equipped with a flame-plate for 5 minutes, add 50 mL of water, and continue boil- ionization detector, helium being used as the carrier gas.ing until a yellow solution is obtained. Transfer the hot plate The following conditions have been found suitable: a 0.25-and the flask to a well-ventilated hood, and bubble sulfur mm × 30-m capillary column coated with a 1-µm layer ofdioxide gas through the solution for 10 minutes, or until the G2; the injection port temperature is maintained at 250°;solution is a clear, brilliant blue color. Rinse the gas delivery the detector temperature is maintained at 300°; and thetube into the flask with a few mL of water, then bubble column temperature is maintained at 100° and pro-carbon dioxide gas through the solution for 30 minutes grammed to rise 10° per minute to 250°. The area of thewhile continuing to boil the solution gently. Cool the solu- C6H9NO peak is not less than 99.0% of the total peak area.tion to about 80°, and titrate with 0.1 N potassium perman- Water, Method 1 ⟨921⟩: not more than 0.1%, determinedganate VS to a yellow-orange endpoint. Perform a complete on 2.5 g, using a mixture of 50 mL of methanol and 10 mLblank determination, and make any necessary correction. of butyrolactone as the solvent.Each mL of 0.1 N potassium permanganate is equivalent to [NOTE—A suitable grade is available from Merck KGaA/9.095 mg of V2O5. Not less than 99.5% is found. EMD chemicals, catalogue number 8.08518.0250, www.Vanadyl Sulfate, VOSO4 · xH2O (anhydrous)—163.00 emdchemicals.com.][27774-13-6]—Blue, hygroscopic crystals. Slowly and usually Washed Sand—See Sand, Washed.incompletely soluble in water. Water, Ammonia-Free, H2O—18.02—Use High-Purity

Assay—Accurately weigh about 400 mg of the dried test Water as defined for Chemical Resistance under Containers—specimen obtained in the test for Water, and transfer with Glass ⟨660⟩.15 to 20 mL of water into a beaker. Add 3 mL of sulfuric Water, Carbon Dioxide-Free—See Water, in the introduc-acid, cover the beaker with a watch glass, and heat on a tory section.steam bath until all dissolves. Cool, dilute with 125 mL of Water, Deaerated—See Water, in the introductory sec-water, and titrate with 0.1 N potassium permanganate VS tion.to the production of a pinkish color that persists for 1 min- Water Vapor Detector Tube—A fuse-sealed glass tube soute: each mL of 0.1 N potassium permanganate is equiva- designed that gas may be passed through it and containinglent to 16.30 mg of VOSO4. Not less than 97% is found. suitable absorbing filters and support media for the indica-

Water—Dry about 1 g, accurately weighed, at 220° to tor, which consists of a selenium sol in suspension in sulfuricconstant weight: it loses not more than 50.0% of its weight. acid.

Pentavalent vanadium—Heat 1 g, accurately weighed, Measuring range: 5 to 250 mg per cubic meter.with 50 mL of water and 5 mL of hydrochloric acid in a flask [NOTE—Available from Draeger Safety, Inc., www.draeger.until dissolved. Cool, add 2 g of potassium iodide, insert the com, or from Gastec Corp., www.gastec.co.jp, distributed instopper, and allow to stand for 30 minutes. Add 50 mL of the USA by www.nextteq.com.]water, and titrate the liberated iodine with 0.1 N sodium Wright’s Stain [68988-92-1]—A mixture of methylenethiosulfate VS, adding 3 mL of starch TS as the indicator. blue, methylene azure, and the eosinates of both, availableCorrect for the volume of thiosulfate consumed by a blank. as a solid and as a solution in methanol. Use a suitableEach mL of 0.1 N thiosulfate is equivalent to 5.095 mg of grade. [NOTE—If a solid is used, dissolve 6.0 g of Wright’svanadium (V). Not more than 0.5% is found, calculated on stain powder (CAS# 68988-92-1, dark green powder) andthe dried basis. 0.6 g of Giemsa stain powder (CAS# 51811-82-6, dark

green to black powder or crystals) in 1000 mL of methanol.Substances not precipitated by ammonia—Dissolve 1.0 gStir overnight, and filter before use.]by heating with 20 mL of water and 2 mL of hydrochloric

Xanthine, C5H4N4O2—152.11 [69-89-6]—White, crys-acid. Dilute with water to about 75 mL, and neutralize totalline powder. Decomposes on heating. Slightly soluble inlitmus paper with ammonia TS. Transfer the solution to awater and in alcohol; soluble in sodium hydroxide TS; spar-cylinder, slowly add 5 mL of ammonia TS and sufficientingly soluble in diluted hydrochloric acid. When subjectedwater to make 100 mL, and allow to stand overnight. De-to the murexide reaction, a purple color is produced withcant 50 mL of the supernatant through a filter, add 5 dropsthe ammonia, but on the subsequent addition of fixed alkaliof sulfuric acid, evaporate to dryness, and ignite: the residuehydroxides, the color is not discharged but is changed toweighs not more than 10 mg (2.0%).violet.Vinyl Acetate, CH3COOCH=CH2—86.09 [108-05-4]—

Liquid. Residue on ignition (Reagent test): negligible, from100 mg.Assay—Inject an appropriate volume into a gas chromat-

ograph (see Chromatography ⟨621⟩) equipped with a flame- Loss on drying ⟨731⟩—Dry it at 105° for 2 hours: it losesionization detector, helium being used as the carrier gas. not more than 1% of its weight.The following conditions have been found suitable: a 0.25- Xanthydrol, C13H10O2—198.22 [90-46-0]—Pale yellow,mm × 30-m capillary column coated with a 1-µm layer of crystalline powder. Insoluble in water; soluble in alcohol, inG2; the injection port temperature is maintained at 100°; chloroform, and in ether. Soluble in glacial acetic acid,the detector temperature is maintained at 300°; and the forming a practically colorless solution; but when the pow-column temperature is maintained at 100° and pro- der is treated with diluted hydrochloric acid, a lemon-yellowgrammed to rise 10° per minute to 150°. The area of the color is produced.


Melting range ⟨741⟩: between 121° and 123°. tions, clarified, and dried to a reddish-yellow to brown pow-der, having a characteristic but not putrescent odor. SolubleResidue on ignition—Ignite 500 mg with 0.5 mL of sulfuricin water, forming a yellow to brown solution, having aacid: the residue weighs not more than 10 mg (2.0%).slightly acid reaction. Contains no added carbohydrate. OneXylene, C8H10—106.17 [1330-20-7]—Use ACS reagentg represents not less than 7.5 g of yeast.grade.

m-Xylene, C6H4(CH3)2—106.17 [108-38-3]—Clear, col- Loss on drying ⟨731⟩—Dry it at 105° to constant weight:orless, flammable liquid. Insoluble in water; miscible with it loses not more than 6% of its weight.alcohol and with ether. Use a suitable grade. Residue on ignition—Ignite 500 mg with 1 mL of sulfuric

o-Xylene, C8H10—106.17 [95-47-6]—Clear, colorless, acid: the residue weighs not more than 75 mg (15%).mobile, flammable liquid. Insoluble in water; miscible with Coagulable protein—Heat a filtered solution (1 in 20) toalcohol and with ether. boiling: no precipitate is formed.

Assay—When examined by gas-liquid chromatography, it Chloride (Reagent test)—It shows not more than 5% ofshows a purity of not less than 95%. The following condi- Cl, calculated as sodium chloride.tions have been found suitable for assaying the substance: ANitrogen content (Reagent test)—Determine by the3-mm × 1.8-m stainless steel column packed with 1.75%

Kjeldahl method, using a test specimen previously dried athydrated aluminum silicate plus 5.0% diisodecyl phthalate105° to constant weight: between 7.2% and 13.0% of N ison support S1. Helium, having a flow rate of about 27.5 mLfound.per minute is the carrier gas, the detector temperature is

Microbial content—NMT 104 cfu/gabout 280°, the injection port temperature is about 180°,Yellow Mercuric Oxide—See Mercuric Oxide, Yellow.and the column temperature is 80°. A flame-ionization de-Zinc, Zn—At. Wt. 65.39 [7440-66-6]—Use ACS rea-tector is employed.

gent grade.Refractive index ⟨831⟩: between 1.5040 and 1.5060,Zinc, Activated—Place zinc pellets in a conical flask, andat 20°.

add a sufficient quantity of a 50-ppm solution of chloropla-p-Xylene, C8H10—106.17 [106-42-3]—Colorless liquid.tinic acid to cover all pellets. Allow the metal to remain inAssay—Inject an appropriate volume into a gas chromat- contact with the solution for 10 min, drain, wash, and dryograph (see Chromatography ⟨621⟩) equipped with a flame- immediately.ionization detector, helium being used as the carrier gas.

Assay—To 5 g of activated zinc add 15 mL of hydrochlo-The following conditions have been found suitable: a 0.25-ric acid, 25 mL of water, 0.1 mL of stannous chloride solu-mm × 30-m capillary column coated with a 1-µm layer oftion (235 mg/mL in hydrochloric acid), and 5 mL of potas-phase G14; the column temperature is maintained at 50°sium iodide solution (166 mg/mL in water). No stain isand programmed to rise 10° per minute to 100°; the injec-produced when in contact with mercuric bromide paper.tion port is maintained at 130°; and the detector is main-Repeat the test for arsenic, using the same reagents andtained at 300°. The area of the C8H10 peak is not less thanadding a solution containing 1 µg of arsenic. An appreciable99% of the total peak area.stain appears when in contact with mercuric bromide paper.Refractive index ⟨831⟩: between 1.493 and 1.497 at 20°. Zinc Acetate, Zn(CH3COO)2 · 2H2O—219.51Xylene Cyanole FF, C25H27N2NaO6S2—538.61 [557-34-6]—Use ACS reagent grade.[2650-17-1]—Gray-blue to dark blue powder. Soluble in Zinc Amalgam—Add 54 g of mossy or granular zinc towater. 100 mL of mercury in a beaker. Heat, with stirring, on a hot

Assay—Transfer about 50 mg, accurately weighed, to a plate under a hood [Caution—mercury vapor is extremely100-mL volumetric flask, dissolve in water, dilute with water toxic] until solution of the zinc is complete or practically so.to volume, and mix. Transfer 2.0 mL of the solution to a Allow to cool to room temperature, and if necessary add50-mL volumetric flask, dilute with pH 7.0 phosphate buffer sufficient mercury to prevent solidification of the amalgam.to volume (See Solutions, in this section), and mix. Using a Transfer the amalgam to a glass-stoppered bottle, and shakesuitable spectrophotometer, 1-cm cells, and water as the a few times with dilute hydrochloric acid (1 in 2), to removeblank, record the absorbance of the solution at the wave- any zinc oxide formed.length of maximum absorbance at about 614 nm. From the Zinc Chloride, Anhydrous, Powdered—Use Zinc Chlorideobserved absorbance, calculate the absorptivity (see Spectro- (USP monograph) that has been dried and powdered.photometry and Light-scattering ⟨851⟩): the absorptivity is not Zinc Sulfate Heptahydrate, ZnSO4 · 7H2O—287.54less than 55.9, corresponding to about 83% of [7446-20-0]—Odorless crystals, granules, or powder.C25H27N2NaO6S2. Melting point ⟨741⟩: 100°.

Loss on drying ⟨731⟩—Dry it at 110° to constant weight: Density: 1.97.it loses not more than 6.0% of its weight. Zirconyl Chloride, Octahydrate, Basic—Use ZirconiumXylose, C5H10O5—150.13 [58-86-6]—Use a suitable Oxychloride.grade. Zirconyl Nitrate, ZrO(NO3)2—231.23 [13826-66-9]—Yeast Extract—A water-soluble, peptone-like derivative of Use a suitable grade.yeast cells (Saccharomyces) prepared under optimum condi-

Indicators and Indicator Test Paperscontaining an acidic group, the acid must first be neutral-INDICATORSized with sodium hydroxide as follows:

Triturate 100 mg of the indicator in a smooth-surfacedIndicators are required in the Pharmacopeial tests and as-mortar with the volume of 0.05 N sodium hydroxide speci-says either to indicate the completion of a chemical reactionfied in the directions for preparing its Test Solution, or within volumetric analysis or to indicate the hydrogen-ion con-the equivalent of 0.02 N sodium hydroxide. When the indi-centration (pH) of solutions. The necessary solutions of in-cator has dissolved, dilute the solution with carbon dioxide-dicators are listed among the Test Solutions, abbreviatedfree water to 200 mL (0.05%). Store the solutions in suitably“TS.”resistant containers, protected from light.Solutions of indicators of the basic type and of the phtha-

leins are prepared by dissolving in alcohol. With indicators

USP 36 Indicators and Indicator Test Papers / Indicators 1207

Listed in ascending order of the lower limit of their range, Eosin Y (Indicator grade Eosin Y, Sodium te-useful pH indicators are: thymol blue, pH 1.2–2.8; methyl trabromofluorescein), C20H6Br4Na2O5—691.86 [17372-87-1]—yellow, pH 2.9–4.0; bromophenol blue, pH 3.0–4.6; bromo- Red to brownish-red pieces or powder. One g dissolves incresol green, pH 4.0–5.4; methyl red, pH 4.2–6.2; bromo- about 2 mL of water and in 50 mL of alcohol. Dye contentcresol purple, pH 5.2–6.8; bromothymol blue, pH 6.0–7.6; about 80%.phenol red, pH 6.8–8.2; thymol blue, pH 8.0–9.2; and thy- Eriochrome Black T [Sodium 1-(1-Hydroxy-2-naphthy-molphthalein, pH 8.6–10.0. lazo)5-nitro-2-naphthol-4-sulfonate], C20H12N3NaO7S—

Alphazurine 2G—Use a suitable grade. 461.38—Brownish-black powder having a faint, metallicAzo Violet [4-(p-Nitrophenylazo)resorcinol], C12H9N3O4— sheen. Soluble in alcohol, in methanol, and in hot water.

259.22—Red powder. It melts at about 193°, with decom- Sensitiveness—To 10 mL of a 1 in 200,000 solution in aposition. mixture of equal parts of methanol and water add sodium

Bismuth Sulfite—Use a suitable grade. hydroxide solution (1 in 100) until the pH is 10: the solu-Brilliant Green—See Brilliant Green in the section Re- tion is pure blue in color and free from cloudiness. Add

agents. 0.01 mg of magnesium ion (Mg): the color of the solutionBrilliant Yellow (C.I. 24890), C26H18N4Na2O8S—592.49— changes to red-violet, and with the continued addition of

Orange to rust-colored powder. Soluble in water. magnesium ion it becomes wine-red.Loss on drying ⟨731⟩—Dry it in vacuum at 60° for 1 hour: Eriochrome Black T Trituration—Grind 200 mg of eri-

it loses not more than 5% of its weight. ochrome black T to a fine powder with 20 g of potassiumBromocresol Blue—Use Bromocresol Green. chloride.Bromocresol Green (Bromocresol Blue; Tetrabromo-m-cre- Litmus—Blue powder, cubes, or pieces. Partly soluble in

sol-sulfonphthalein), C21H14Br4O5S—698.01—White or pale water and in alcohol. Transition interval: from approximatelybuff-colored powder. Slightly soluble in water; soluble in al- pH 4.5 to 8. Color change: from red to blue. Litmus is un-cohol and in solutions of alkali hydroxides. Transition inter- suitable for determining the pH of alkaloids, carbonates, andval: from pH 4.0 to 5.4. Color change: from yellow to blue. bicarbonates.

Bromocresol Green Sodium Salt—Use a suitable grade. Malachite Green Oxalate, [C23H25N2+]2 · [C2HO4−]2 ·Bromocresol Purple (Dibromo-o-cresolsulfonphthalein), C2H2O4—927.00—The oxalate salt, crystallized with oxalic

C21H16Br2O5S—540.22—White to pink, crystalline powder. acid, of a triphenylmethane dye. Dark-green powder, havingInsoluble in water; soluble in alcohol and in solutions of a metallic luster. Sparingly soluble in water; soluble in glacialalkali hydroxides. Transition interval: from pH 5.2 to 6.8. acetic acid. Transition interval: from pH 0.0 to 2.0. ColorColor change: from yellow to purple. change: from yellow to green.

Bromocresol Purple Sodium Salt, C21H15Br2O5SNa— Methyl Orange (Helianthin or Tropaeolin D),562.20—Black powder. Soluble in water. Transition interval: C14H14N3NaO3S—327.33—The sodium salt of dimethylami-from pH 5.0 to 6.8. Color change: from greenish yellow to noazobenzene sulfonic acid or dimethylaminoazobenzenepurple-violet. sodium sulfonate. An orange-yellow powder or crystalline

scales. Slightly soluble in cold water; readily soluble in hotMelting range ⟨741⟩: between 261° and 264°.water; insoluble in alcohol. Transition interval: from pH 3.2Bromophenol Blue (3′,3′′,5′,5′′-Tetrabromophenol-to 4.4. Color change: from pink to yellow.sulfonphthalein), C19H10Br4O5S—669.96—Pinkish crystals. In-

Methyl Red (2-[[4-(Dimethylamino)phenyl]azo]benzoic Acidsoluble in water; soluble in alcohol and in solutions of alkaliHydrochloride), 2-[4-(CH3)2NC6H4N:N]C6H4COOH · HCl—hydroxides. Transition interval: from pH 3.0 to 4.6. Color305.76—Dark-red powder or violet crystals. Sparingly solu-change: from yellow to blue.ble in water; soluble in alcohol. Transition interval: from pHBromophenol Blue Sodium—The sodium salt of 3′,3′′,5′,4.2 to 6.2. Color change: from red to yellow.5′′ (Tetrabromophenolsulfonphthalein), C19H9Br4O5SNa—

Methyl Red Sodium—The sodium salt of 2-[[4-(dimeth-646.36—Pinkish crystals. Soluble in water and in alcohol.ylamino)phenyl]azo]benzoic acid. 2-[4-(CH3)2NC6H4N:N]Transition interval: from pH 3.0 to 4.6. Color change: fromC6H4COONa—291.28—Orange-brown powder. Freely solu-yellow to blue.ble in cold water and in alcohol. Transition interval: from pHBromothymol Blue (3′,3′′-Dibromothymolsulfonphthalein),4.2 to 6.2. Color change: from red to yellow.C27H28Br2O5S—624.38—Cream-colored powder. Insoluble in

Methyl Yellow (p-Dimethylaminoazobenzene), C14H15N3—water; soluble in alcohol and in solutions of alkali hydrox-225.29—Yellow crystals, melting between 114° and 117°.ides. Transition interval: from pH 6.0 to 7.6. Color change:Insoluble in water; soluble in alcohol, in benzene, in chloro-from yellow to blue.form, in ether, in dilute mineral acids, and in oils. TransitionCongo Red—See Congo Red in the section Reagents.interval: from pH 2.9 to 4.0. Color change: from red toCresol Red (o-Cresolsulfonphthalein), C21H18O5S—382.43—yellow.Red-brown powder. Slightly soluble in water; soluble in al-

p-Naphtholbenzein (4-[α-(4-Hydroxy-1-naph-cohol and in dilute solutions of alkali hydroxides. Transitionthyl)benzylidene]-1(4H)-naphthalenone), (4-HOC10H6)interval: from pH 7.2 to 8.8. Color change: from yellow toC(:C10H6-4:O)(C6H5)—374.43—Reddish brown powder. In-red.soluble in water; soluble in alcohol, in benzene, in ether,Crystal Violet (Hexamethyl-p-rosaniline Chloride),and in glacial acetic acid. Transition interval: from pH 8.8 toC25H30ClN3—407.98—Dark-green crystals. Slightly soluble in10.0. Color change: from orange to green.water; sparingly soluble in alcohol and in glacial acetic acid.

Neutral Red (3-Amino-7-dimethylamino-2-methylphenazineIts solutions are deep violet in color.Monohydrochloride), C15H16N4 · HCl—288.78—Reddish to ol-Sensitiveness—Dissolve 100 mg in 100 mL of glacial acetic ive-green, coarse powder. Sparingly soluble in water and inacid, and mix. Pipet 1 mL of the solution into a 100-mL alcohol. Transition interval: from pH 6.8 to 8.0. Colorvolumetric flask, and dilute with glacial acetic acid to vol- change: from red to orange.ume: the solution is violet-blue in color and does not show Nile Blue Hydrochloride (Nile Blue A, as the hydrochloride;a reddish tint. Pipet 20 mL of the diluted solution into a 5-Amino-9- (diethylamino)benzo[a]phenoxazin-7-ium chloride),beaker, and titrate with 0.1 N perchloric acid VS, adding the C20H20ClN3O—353.85—Slightly soluble in alcohol and inperchloric acid slowly from a microburet: not more than glacial acetic acid. Transition interval: from pH 9.0 to 13.0.0.10 mL of 0.1 N perchloric acid is required to produce an Color change: from blue to pink.emerald-green color. Oracet Blue B (Solvent Blue 19)—A mixture of 1-methyl-4,5-Dihydroxy-3-(p-sulfophenylazo)-2,7- amino-4-anilinoanthraquinone (C21H16N2O2) and 1-amino-naphthalenedisulfonic Acid, Trisodium Salt—See 2- 4-anilinoanthraquinine (C20H14N2O2). Where used for titra-(4-Sulfophenylazo)-1,8-dihydroxy-3,6-naphthalenedisulfonic tion in non-aqueous media, it changes from blue (basic)Acid, Trisodium Salt. through purple (neutral) to pink (acidic).

1208 Indicators / Indicators and Indicator Test Papers USP 36

Phenol Red [4,4′-(3H-2,1-Benzoxathiol-3-ylidene)diphenol, Phosphate (Reagent test)—Cut 5 strips into small pieces,S,S-Dioxide], C19H14O5S—354.38—Crystalline powder, vary- mix with 500 mg of magnesium nitrate in a porcelain cruci-ing in color from bright to dark red. Very slightly soluble in ble, and ignite. To the residue add 5 mL of nitric acid, andwater; freely soluble in solutions of alkali carbonates and evaporate to dryness: the residue shows not more thanhydroxides; slightly soluble in alcohol. Transition interval: 0.02 mg of PO4.from pH 6.8 to 8.2. Color change: from yellow to red. Residue on ignition—Ignite carefully 10 strips of the paper

Phenolphthalein [3,3-Bis(p-hydroxyphenyl)phthalide], to constant weight: the weight of the residue correspondsC20H14O4—318.32—White or faintly yellowish-white, crystal- to not more than 0.4 mg per strip of about 3 square cm.line powder. Insoluble in water; soluble in alcohol. Transition Rosin acids—Immerse a strip of the blue paper in a solu-interval: from pH 8.0 to 10.0. Color change: from colorless tion of 100 mg of silver nitrate in 50 mL of water: the colorto red. of the paper does not change in 30 seconds.

Quinaldine Red (5-Dimethylamino-2-styrylethylquinolinium Sensitiveness—Drop a 10- to 12-mm strip into 100 mL ofIodide), C21H23IN2—430.33—Dark blue-black powder. Spar- 0.0005 N acid contained in a beaker, and stir continuously:ingly soluble in water; freely soluble in alcohol. Melts at the color of the paper is changed within 45 seconds. Theabout 260°, with decomposition. Transition interval: from 0.0005 N acid is prepared by diluting 1 mL of 0.1 N hydro-pH 1.4 to 3.2. Color change: from colorless to red. chloric acid with freshly boiled and cooled purified water to

2-(4-Sulfophenylazo)-1,8-dihydroxy-3,6-naphtha- 200 mL.lenedisulfonic Acid, Trisodium Salt (4,5-Dihydroxy-3-(p- Litmus Paper, Red—Usually about 6 × 50 mm in size. Redsulfophenylazo)-2,7-naphthalenedisulfonic Acid, Trisodium litmus paper meets the requirements of the tests for Phos-Salt), C16H9N2O11S3Na3—570.42—Red powder. Soluble in phate, Residue on ignition, and Rosin acids, under Litmus Pa-water. per, Blue.

Thymol Blue (Thymolsulfonphthalein), C27H30O5S— Sensitiveness—Drop a 10- to 12-mm strip into 100 mL of466.59—Dark-colored, crystalline powder. Slightly soluble in 0.0005 N sodium hydroxide contained in a beaker, and stirwater; soluble in alcohol and in dilute alkali solutions. Acid— continuously: the color of the paper changes withinTransition interval: from pH 1.2 to 2.8. Color change: from 30 seconds. The 0.0005 N sodium hydroxide is prepared byred to yellow. Alkaline—Transition interval: from pH 8.0 to diluting 1 mL of 0.1 N sodium hydroxide with freshly boiled9.2. Color change: from yellow to blue. and cooled purified water to 200 mL.

Thymolphthalein, C28H30O4—430.54—White to slightly Mercuric Bromide Test Paper—Place a 50 mg/mL solu-yellow, crystalline powder. Insoluble in water; soluble in al- tion of mercuric bromide in dehydrated alcohol in a dish,cohol and in solutions of alkali hydroxides. Transition inter- and immerse in it pieces of white filter paper weighingval: from pH 9.3 to 10.5. Color change: from colorless to 80 g/m2 (speed of filtration = filtration time expressed in sblue. for 100 mL of water at 20° with a filter surface of 10 cm2

Xylenol Orange, (N,N′-[3H-2,1-Benzoxathiol-3-ylidenebis- and a constant pressure of 6.7 kPa; 40–60 s), each measur-[(6-hydroxy-5-methyl-3,1-phenylene)methylene]]bis[N-(carboxy- ing 1.5 cm by 20 cm and folded in the middle. Allow themethyl)glycine]S,S-dioxide), C31H28N2Na4O13S—760.58—Or- excess of liquid to drain, and allow the paper to dry, pro-ange powder. Soluble in alcohol and in water. In acid solu- tected from light, suspended over a nonmetallic thread. Dis-tion, it is lemon-yellow in color, and its metal complexes are card 1 cm from each end of each strip, and cut the remain-intensely red. It yields a distinct endpoint where a metal der into 1.5-cm squares or discs of 1.5-cm diameter. Storesuch as bismuth, cadmium, lanthanum, lead, mercury, scan- in a glass-stoppered container wrapped with black paper.dium, thorium, or zinc is titrated with edetate disodium. Methyl Green–Iodomercurate Paper—Immerse thin

strips of suitable filter paper in a 40 g per L solution ofmethyl green, and allow to air-dry. Immerse the strips for

INDICATORS AND TEST PAPERS 1 hour in a solution containing 140 g per L of potassiumiodide and 200 g per L of mercuric iodide. Wash with water

Indicator and test papers are strips of paper of suitable until the washings are practically colorless, and allow to air-dimension and grade (see Filter Paper, Quantitative, in the dry. Store protected from light, and use within 48 hours.section Reagents) impregnated with an indicator or a rea- Methyl Yellow Paper—Use a 1 in 2000 solution ofgent that is sufficiently stable to provide a convenient form methyl yellow in alcohol.of the impregnated substance. Some test papers may be pH Indicator Paper, Short-Range—Use a suitable grade.obtained from commercial sources of laboratory supplies. Phenolphthalein Paper—Use a 1 in 1000 solution ofThose required in Pharmacopeial tests and assays may be phenolphthalein in diluted alcohol.prepared as directed in the following paragraphs, by means Starch Iodate Paper—Use a mixture of equal volumes ofof the solutions specified, or to meet the tests set forth starch TS and potassium iodate solution (1 in 20).herein under the individual titles. Starch Iodide Paper—Use a solution of 500 mg of potas-

Treat strong, white filter paper with hydrochloric acid, sium iodide in 100 mL of freshly prepared starch TS.and wash with water until the last washing no longer shows Thiazole Yellow Paper—Use a 1 in 2000 solution of thia-an acid reaction to methyl red. Then treat with ammonia zole yellow in water.TS, and wash again with water until the last washing is not Turmeric Paper—Use a solution prepared as follows:alkaline to phenolphthalein. Macerate 20 g of powdered turmeric, the dried root of Cur-

After thorough drying, saturate the paper with the proper cuma longa Linne (Fam. Zingiberaceae), with four 100-mLstrength of indicator solutions, and carefully dry in still air, portions of cold water, decanting the clear liquid portionunless otherwise specified, by suspending it from rods of each time and discarding it. Dry the residue at a tempera-glass or other inert material in a space free from acid, alkali, ture not over 100°. Macerate with 100 mL of alcohol forand other fumes. several days, and filter.

Cut the paper into strips of convenient size, and store the Sensitiveness—Dip a strip of the paper, of about 1.5-cmpapers in well-closed containers, protected from light and length, in a solution of 1.0 mg of boric acid in 5 mL ofmoisture. water, previously mixed with 1 mL of hydrochloric acid. Af-

Cupric Sulfate Test Paper—Use cupric sulfate TS. ter 1 minute remove the paper from the liquid, and allow itLead Acetate Test Paper—Usually about 6 × 80 mm in to dry: the yellow color changes to brown. Then moisten

size. Use lead acetate TS, and dry the paper at 100°, avoid- the paper with ammonia TS: the color of the paper changesing contact with metal. to greenish black.

Litmus Paper, Blue—Usually about 6 × 50 mm in size. Itmeets the requirements of the following tests.

USP 36 Solutions / Buffer Solutions 1209

Solutionstablets, and buffer solids may be obtained from commercialBUFFER SOLUTIONSsources in convenient prepackaged form. Such preparationsare available for the entire working range in pharmaceuticalThe successful completion of many Pharmacopeial testsanalysis, but are not recommended for pH meter standardi-and assays requires adjustment to or maintenance of a spec-zation (see pH ⟨791⟩).ified pH by the addition of buffer solutions. In pH measure-

The required reagents are described in the section, Re-ments, standard buffer solutions are required for referenceagents. Previously dry the crystalline reagents, except thepurposes. For convenience, the preparation of these solu-boric acid and sodium acetate trihydrate, at 110° to 120°tions is in some instances described in the sections in whichfor 1 hour.their use is specified; i.e., five separate phosphate buffers are

[NOTE—Where water is specified for solution or dilutiondescribed under Antibiotics—Microbial Assays ⟨81⟩, and sev-of test substances in pH determinations, use carbon dioxide-eral miscellaneous single-purpose solutions are described infree water.]the individual monographs.

Store the prepared solutions in chemically resistant, tightA solution is said to be buffered if it resists changes in thecontainers such as Type I glass bottles. Use the solutionsactivity of an ion on the addition of substances that arewithin 3 months.expected to change the activity of that ion. Buffers are sub-

Standard Buffer Solutions for various ranges between pHstances or combinations of substances that impart this resis-1.2 and 10.0 may be prepared by appropriate combinationstance to a solution. Buffered solutions are systems in whichof the solutions described herein, used in the proportionsthe ion is in equilibrium with substances capable of remov-shown in the accompanying table. The volumes shown ining or releasing the ion.the table are for 200 mL of buffer solution, except that theBuffer capacity refers to the amount of material that mayvolumes shown for Acetate Buffer are used to preparebe added to a solution without causing a significant change1000 mL of buffer solution.in ion activity. It is defined as the ratio of acid or base

1. Hydrochloric Acid, 0.2 M, and Sodium Hydroxide, 0.2added (in gram-equivalents per liter) to the change in pHM—Prepare and standardize as directed under Volu-(in pH units). The capacity of a buffered solution is adjustedmetric Solutions.to the conditions of use, usually by adjustment of the con-

2. Potassium Biphthalate, 0.2 M—Dissolve 40.85 g of po-centrations of buffer substances.tassium biphthalate [KHC6H4(COO)2] in water, and di-Buffers are used to establish and maintain an ion activitylute with water to 1000 mL.within narrow limits. The most common systems are used

3. Potassium Phosphate, Monobasic 0.2 M—Dissolve(a) to establish hydrogen-ion activity for the calibration of27.22 g of monobasic potassium phosphate (KH2PO4)pH meters, (b) in the preparation of dosage forms that ap-in water, and dilute with water to 1000 mL.proach isotonicity, (c) in analytical procedures, and (d) to

4. Boric Acid and Potassium Chloride, 0.2 M—Dissolvemaintain stability of various dosage forms. Buffers used in12.37 g of boric acid (H3BO3) and 14.91 g of potas-physiological systems are carefully chosen so as not to inter-sium chloride (KCl) in water, and dilute with water tofere with pharmacological activity of the medicament or1000 mL.normal function of the organism. It is essential that buffers

5. Potassium Chloride, 0.2 M—Dissolve 14.91 g of potas-used in chemical analysis be compatible with the substancesium chloride (KCl) in water, and dilute with water todetermined and the reagents used.1000 mL.Standard Buffer Solutions—Standard solutions of definite 6. Acetic Acid, 2 N—Prepare and standardize as directedpH are readily available in buffer solutions prepared from under Volumetric Solutions.the appropriate reagents. In addition, buffer solutions, buffer

Composition of Standard Buffer SolutionsHydrochloric Acid Buffer

Place 50 mL of the potassium chloride solution in a 200-mL volumetric flask, add the specified volume of the hydrochloric acid solution, then add waterto volume.

pH 1.2 1.3 1.4 1.5 1.6 1.7 1.8 1.9 2.0 2.1 2.20.2 M HCl, mL 85.0 67.2 53.2 41.4 32.4 26.0 20.4 16.2 13.0 10.2 7.8

Acid Phthalate BufferPlace 50 mL of the potassium biphthalate solution in a 200-mL volumetric flask, add the specified volume of the hydrochloric acid solution, thenadd water to volume.

pH 2.2 2.4 2.6 2.8 3.0 3.2 3.4 3.6 3.8 4.00.2 M HCl, mL 49.5 42.2 35.4 28.9 22.3 15.7 10.4 6.3 2.9 0.1

Neutralized Phthalate BufferPlace 50 mL of the potassium biphthalate solution in a 200-mL volumetric flask, add the specified volume of the sodium hydroxide solution, thenadd water to volume.

pH 4.2 4.4 4.6 4.8 5.0 5.2 5.4 5.6 5.80.2 M NaOH, mL 3.0 6.6 11.1 16.5 22.6 28.8 34.1 38.8 42.3

1210 Buffer Solutions / Solutions USP 36

Phosphate BufferPlace 50 mL of the monobasic potassium phosphate solution in a 200-mL volumetric flask, add the specified volume of the sodium hydroxidesolution, then add water to volume.

pH 5.8 6.0 6.2 6.4 6.6 6.8 7.0 7.2 7.4 7.6 7.8 8.00.2 M NaOH, mL 3.6 5.6 8.1 11.6 16.4 22.4 29.1 34.7 39.1 42.4 44.5 46.1

Alkaline Borate BufferPlace 50 mL of the boric acid and potassium chloride solution in a 200-mL volumetric flask, add the specified volume of the sodium hydroxidesolution, then add water to volume.

pH 8.0 8.2 8.4 8.6 8.8 9.0 9.2 9.4 9.6 9.8 10.00.2 M NaOH, mL 3.9 6.0 8.6 11.8 15.8 20.8 26.4 32.1 36.9 40.6 43.7

Acetate BufferPlace the specified amount of sodium acetate NaC2H3O2 · 3H2O in a 1000-mL volumetric flask, add the specified volume of the acetic acid solution,then add water to volume, and mix.

pH 4.1 4.3 4.5 4.7 4.9 5.1 5.2 5.3 5.4 5.5pH (measured) 4.10 4.29 4.51 4.70 4.90 5.11 5.18 5.30 5.40 5.48NaC2H3O2 · 3H2O, g 1.5 1.99 2.99 3.59 4.34 5.08 5.23 5.61 5.76 5.982 N CH3COOH, mL 19.5 17.7 14.0 11.8 9.1 6.3 5.8 4.4 3.8 3.0

Ferric Chloride CS—Dissolve about 55 g of ferric chlorideCOLORIMETRIC SOLUTIONS (CS)(FeCl3 · 6H2O) in enough of a mixture of 25 mL of hydro-chloric acid and 975 mL of water to make 1000 mL. Pipet(For the Preparation of Matching Fluids, see Color and10 mL of this solution into a 250-mL iodine flask, add 15 mLAchromicity ⟨631⟩.)of water, 3 g of potassium iodide, and 5 mL of hydrochloricThese solutions are used in the preparation of the colori-acid, and allow the mixture to stand for 15 minutes. Dilutemetric standards for certain drugs, and for the carbonizationwith 100 mL of water, and titrate the liberated iodine withtests with sulfuric acid that are specified in several mono-0.1 N sodium thiosulfate VS, adding 3 mL of starch TS asgraphs. Store the solutions in suitably resistant, tightthe indicator. Perform a blank determination with the samecontainers.quantities of the same reagents, and make any necessaryComparison of colors as directed in the Pharmacopeialcorrection. Each mL of 0.1 N sodium thiosulfate is equiva-tests preferably is made in matched color-comparison tubeslent to 27.03 mg of FeCl3 · 6H2O. Adjust the final volume ofor in a suitable colorimeter under conditions that ensurethe solution by the addition of enough of the mixture ofthat the colorimetric reference solution and that of the spec-hydrochloric acid and water so that each mL containsimen under test are treated alike in all respects. The com-45.0 mg of FeCl3 · 6H2O.parison of colors is best made in layers of equal depth, and

viewed transversely against a white background (see alsoVisual Comparison under Spectrophotometry and Light-Scatter- INDICATOR SOLUTIONSing ⟨851⟩). It is particularly important that the solutions becompared at the same temperature, preferably 25°. See TEST SOLUTIONS.

Cobaltous Chloride CS—Dissolve about 65 g of cobaltouschloride (CoCl2 · 6H2O) in enough of a mixture of 25 mL of

TEST SOLUTIONS (TS)hydrochloric acid and 975 mL of water to make 1000 mL.Pipet 5 mL of this solution into a 250-mL iodine flask, add

Certain of the following test solutions are intended for use5 mL of hydrogen peroxide TS and 15 mL of sodium hy-as acid-base indicators in volumetric analyses. Such solutionsdroxide solution (1 in 5), boil for 10 minutes, cool, and addshould be so adjusted that when 0.15 mL of the indicator2 g of potassium iodide and 20 mL of dilute sulfuric acid (1solution is added to 25 mL of carbon dioxide-free water,in 4). When the precipitate has dissolved, titrate the liber-0.25 mL of 0.02 N acid or alkali, respectively, will produceated iodine with 0.1 N sodium thiosulfate VS, adding 3 mLthe characteristic color change. Similar solutions are in-of starch TS as the indicator. Perform a blank determinationtended for use in pH measurement. Where no special direc-with the same quantities of the same reagents, and maketions for their preparation are given, the same solution isany necessary correction. Each mL of 0.1 N sodium thiosul-suitable for both purposes.fate is equivalent to 23.79 mg of CoCl2 · 6H2O. Adjust the

Where it is directed that a volumetric solution be used asfinal volume of the solution by the addition of enough ofthe test solution, standardization of the solution used as TSthe mixture of hydrochloric acid and water so that each mLis not required.contains 59.5 mg of CoCl2 · 6H2O.

In general, the directive to prepare a solution “fresh” indi-Cupric Sulfate CS—Dissolve about 65 g of cupric sulfatecates that the solution is of limited stability and must be(CuSO4 · 5H2O) in enough of a mixture of 25 mL of hydro-prepared on the day of use.chloric acid and 975 mL of water to make 1000 mL. Pipet

For the preparation of Test Solutions, use reagents of the10 mL of this solution into a 250-mL iodine flask, add 40 mLquality described under Reagents.of water, 4 mL of acetic acid, 3 g of potassium iodide, and

Acetaldehyde TS—Mix 4 mL of acetaldehyde, 3 mL of5 mL of hydrochloric acid, and titrate the liberated iodinealcohol, and 1 mL of water. Prepare this solution fresh.with 0.1 N sodium thiosulfate VS, adding 3 mL of starch TS

Acetate Buffer TS—Dissolve 320 g of ammonium acetateas the indicator. Perform a blank determination with thein 500 mL of water, add 5 mL of glacial acetic acid, dilutesame quantities of the same reagents, and make any neces-with water to 1000.0 mL, and mix. This solution has a pHsary correction. Each mL of 0.1 N sodium thiosulfate isbetween 5.9 and 6.0.equivalent to 24.97 mg of CuSO4 · 5H2O. Adjust the final

Acetic Acid, Glacial, TS—Determine the water contentvolume of the solution by the addition of enough of theof a specimen of glacial acetic acid by the Titrimetric Methodmixture of hydrochloric acid and water so that each mL(see Water Determination ⟨921⟩). If the acid contains morecontains 62.4 mg of CuSO4 · 5H2O.than 0.4% of water, add a few mL of acetic anhydride, mix,allow to stand overnight, and again determine the water

USP 36 Solutions / Test Solutions 1211

content. If the acid contains less than 0.02% of water, add monia. Specific gravity: about 0.80. It contains between 9%sufficient water to make the final concentration between and 11% of NH3. Store it in alkali-resistant containers, in a0.02% and 0.4%, mix, allow to stand overnight, and again cold place.determine the water content. Repeat the adjustment with Ammonia TS, Stronger—Use Ammonia Water, Strongeracetic anhydride or water, as necessary, until the resulting (see in the section Reagents).solution shows a water content of not more than 0.4%. Ammonia–Ammonium Chloride Buffer TS—Dissolve

Acetic Acid, Strong, TS—Add 300.0 mL of glacial acetic 67.5 g of ammonium chloride in water, add 570 mL of am-acid, and dilute with water to 1000 mL. This solution con- monium hydroxide, and dilute with water to 1000 mL.tains about 30% (v/v) of CH3COOH and has a concentration Ammonia–Cyanide TS—Dissolve 2 g of potassium cya-of about 5 N. nide in 15 mL of ammonium hydroxide, and dilute with

Acetic Acid–Ammonium Acetate Buffer TS—Dissolve water to 100 mL.77.1 g of ammonium acetate in water, add 57 mL of glacial Ammoniacal Potassium Ferricyanide TS—Dissolve 2 gacetic acid, and dilute with water to 1000 mL. of potassium ferricyanide in 75 mL of water, add 25 mL of

Acetone, Buffered, TS—Dissolve 8.15 g of sodium ace- ammonium hydroxide, and mix.tate and 42 g of sodium chloride in about 100 mL of water, Ammoniated Cupric Oxide TS—See Cupric Oxide, Am-and add 68 mL of 0.1 N hydrochloric acid and 150 mL of moniated, TS.acetone. Mix, and dilute with water to 500 mL. Ammonium Acetate TS—Dissolve 10 g of ammonium

Acid Ferric Chloride TS—Mix 60 mL of glacial acetic acetate in water to make 100 mL.acid with 5 mL of sulfuric acid, add 1 mL of ferric chloride Ammonium Carbonate TS—Dissolve 20 g of ammoniumTS, mix, and cool. carbonate and 20 mL of ammonia TS in water to make

Acid Ferrous Sulfate TS—See Ferrous Sulfate, Acid, TS. 100 mL.Acid Stannous Chloride TS—See Stannous Chloride, Acid, Ammonium Carbonate TS 2—Prepare a 158-mg/mL so-

TS. lution of ammonium carbonate in water.Ammonium Chloride TS—Dissolve 10.5 g of ammonium

chloride in water to make 100 mL.Change to read: Ammonium Chloride–Ammonium Hydroxide TS—Mixequal volumes of water and ammonium hydroxide, and sat-

Acid Stannous Chloride TS, Stronger—See •Stannous urate with ammonium chloride.Chloride, Acid, Stronger, TS.• (ERR 1-Jul-2012) Ammonium Molybdate TS—Dissolve 6.5 g of finely

Albumen TS—Carefully separate the white from the yolk powdered molybdic acid in a mixture of 14 mL of waterof a strictly fresh hen’s egg. Shake the white with 100 mL of and 14.5 mL of ammonium hydroxide. Cool the solution,water until mixed and all but the chalaza has undergone and add it slowly, with stirring, to a well-cooled mixture ofsolution; then filter. Prepare the solution fresh. 32 mL of nitric acid and 40 mL of water. Allow to stand for

Alcohol–Phenol TS—Dissolve 780 mg of phenol in alco- 48 hours, and filter through a fine-porosity, sintered-glasshol to make 100 mL. crucible. This solution deteriorates upon standing and is un-

Alcoholic TS—It contains 95 parts of specially suitable for use if, upon the addition of 2 mL of dibasic so-denaturated alcohol 3A with 5 parts of isopropyl alcohol. dium phosphate TS to 5 mL of the solution, an abundantThe final concentrations are approximately 90% alcohol, 5% yellow precipitate does not form at once or after slightmethanol, and 5% isopropanol. warming. Store it in the dark. If a precipitate forms during

[NOTE—A suitable grade is available as Reagent alcohol, storage, use only the clear supernatant.catalog number R8382, available at www.sigma-aldrich. Ammonium Oxalate TS—Dissolve 3.5 g of ammoniumcom.] oxalate in water to make 100 mL.

Alcoholic Ammonia TS—See Ammonia TS, Alcoholic. Ammonium Phosphate, Dibasic, TS (AmmoniumAlcoholic Mercuric Bromide TS—See Mercuric Bromide Phosphate TS)—Dissolve 13 g of dibasic ammonium phos-

TS, Alcoholic. phate in water to make 100 mL.Alcoholic Potassium Hydroxide TS—See Potassium Hy- Ammonium Polysulfide TS—Yellow liquid, made by sat-

droxide TS, Alcoholic. urating ammonium sulfide TS with sulfur.Alkaline Cupric Citrate TS—See Cupric Citrate TS, Alka- Ammonium Pyrrolidinedithiocarbamate, Saturated,

line. TS—Add about 10 g of ammonium pyrrolidinedithiocarba-Alkaline Cupric Citrate TS 2—See Cupric Citrate TS 2, mate to a 1000-mL volumetric flask, and dilute with water

Alkaline. to volume.Alkaline Cupric Iodide TS—See Cupric Iodide TS, Alkaline. Ammonium Reineckate TS—Shake about 500 mg ofAlkaline Cupric Tartrate TS (Fehling’s Solution)—See Cu- ammonium reineckate with 20 mL of water frequently dur-

pric Tartrate TS, Alkaline. ing 1 hour, and filter. Use within 2 days.Alkaline Mercuric–Potassium Iodide TS—See Ammonium Sulfide TS—Use ACS reagent-grade Ammo-

Mercuric–Potassium Iodide TS, Alkaline. nium Sulfide Solution.Alkaline Picrate TS—See Picrate TS, Alkaline. Ammonium Thiocyanate TS—Dissolve 8 g of ammo-Alkaline Sodium Hydrosulfite TS—See Sodium Hydrosul- nium thiocyanate in water to make 100 mL.

fite TS, Alkaline. Ammonium Vanadate TS—Dissolve 2.5 g of ammoniumAmaranth TS—Dissolve 20 mg of amaranth in 10 mL of vanadate in 500 mL of boiling water, cool, and add 20 mL

water. of nitric acid. Mix, cool, and add water to make 1 L. StoreAminonaphtholsulfonic Acid TS—Accurately weigh 5 g in polyethylene containers.

of sodium sulfite, 94.3 g of sodium bisulfite, and 700 mg of Anthrone TS—Within 12 hours of use, rapidly dissolve1,2,4-aminonaphtholsulfonic acid, and mix. Prepare amino- 35 mg of anthrone in a hot mixture of 35 mL of water andnaphtholsulfonic acid TS fresh on the day of use by dissolv- 65 mL of sulfuric acid. Immediately cool in an ice bath toing 1.5 g of the dry mixture in 10 mL of water. room temperature, and filter through glass wool. Allow the

Ammonia TS—It contains between 9.5% and 10.5% of solution to stand at room temperature for 30 minutes beforeNH3. Prepare by diluting 350 mL of Ammonia Water, use.Stronger (see in the section, Reagents) with water to make Antimony Trichloride TS—Dissolve 20 g of antimony1000 mL. trichloride in chloroform to make 100 mL. Filter if necessary.

Ammonia TS 2—Prepare by diluting 13.5 mL of Ammo- Barium Chloride TS—Dissolve 12 g of barium chloride innia Water, Stronger (see Reagent Specifications in the section water to make 100 mL.Reagents) with water to make 100 mL. Barium Hydroxide TS—A saturated solution of barium

Ammonia TS, Alcoholic—A solution of ammonia gas in hydroxide in recently boiled water. Prepare the solutionalcohol. Clear, colorless liquid having a strong odor of am- fresh.

1212 Test Solutions / Solutions USP 36

Barium Nitrate TS—Dissolve 6.5 g of barium nitrate in Cobaltous Chloride TS—Dissolve 2 g of cobaltous chlo-water to make 100 mL. ride in 1 mL of hydrochloric acid and sufficient water to

Betanaphthol TS—See 2-Naphthol TS. make 100 mL.Biuret Reagent TS—Dissolve 1.5 g of cupric sulfate and Congo Red TS—Dissolve 500 mg of congo red in a mix-

6.0 g of potassium sodium tartrate in 500 mL of water in a ture of 10 mL of alcohol and 90 mL of water.1000-mL volumetric flask. Add 300 mL of carbonate-free so- m-Cresol Purple TS—Dissolve 0.10 g of metacresol pur-dium hydroxide solution (1 in 10), dilute with carbonate- ple in 13 mL of 0.01 N sodium hydroxide, dilute with waterfree sodium hydroxide solution (1 in 10) to 1000 mL, and to 100 mL, and mix.mix. Cresol Red TS—Triturate 100 mg of cresol red in a mor-

Blue Tetrazolium TS—Dissolve 500 mg of blue tet- tar with 26.2 mL of 0.01 N sodium hydroxide until solutionrazolium in alcohol to make 100 mL. is complete, then dilute the solution with water to 250 mL.

Brilliant Blue G TS—Transfer 25 mg of brilliant blue G to Cresol Red–Thymol Blue TS—Add 15 mL of thymol bluea 100-mL volumetric flask, add 12.5 mL of alcohol and TS to 5 mL of cresol red TS, and mix.25 mL of phosphoric acid, dilute with water to volume, and Crystal Violet TS—Dissolve 100 mg of crystal violet inmix. 10 mL of glacial acetic acid.

Bromine TS (Bromine Water)—A saturated solution of Cupric Acetate TS—Dissolve 100 mg of cupric acetate inbromine, prepared by agitating 2 to 3 mL of bromine with about 5 mL of water to which a few drops of acetic acid100 mL of cold water in a glass-stoppered bottle, the stop- have been added. Dilute to 100 mL, and filter, if necessary.per of which should be lubricated with petrolatum. Store it Cupric Acetate TS, Stronger (Barfoed’s Reagent)—Dis-in a cold place, protected from light. solve 13.3 g of cupric acetate in a mixture of 195 mL of

Bromine–Sodium Acetate TS—Dissolve 100 g of sodium water and 5 mL of acetic acid.acetate in 1000 mL of glacial acetic acid, add 50 mL of bro- Cupric-Ammonium Sulfate TS—To cupric sulfate TS addmine, and mix. ammonia TS, dropwise, until the precipitate initially formed

p-Bromoaniline TS—Add 8 g of p-bromoaniline to a is nearly but not completely dissolved. Allow to settle, andmixture of 380 mL of thiourea-saturated glacial acetic acid, decant the clear solution. Prepare this solution fresh.10 mL of sodium chloride solution (1 in 5), 5 mL of oxalic Cupric Citrate TS—Dissolve 25 g of cupric sulfate, 50 gacid solution (1 in 20), and 5 mL of dibasic sodium phos- of citric acid, and 144 g of anhydrous sodium carbonate inphate solution (1 in 10) in a low-actinic glass bottle. Mix, water, and dilute with water to 1000 mL.and allow to stand overnight before using. Protect from Cupric Citrate TS, Alkaline—With the aid of heat, dis-light, and use within 7 days. solve 173 g of dihydrated sodium citrate and 117 g of mon-

Bromocresol Blue TS—Use Bromocresol Green TS. ohydrated sodium carbonate in about 700 mL of water, andBromocresol Green TS—Dissolve 50 mg of bromocresol filter through paper, if necessary, to obtain a clear solution.

green in 100 mL of alcohol, and filter if necessary. In a separate container dissolve 17.3 g of cupric sulfate inBromocresol Green–Methyl Red TS—Dissolve 0.15 g of about 100 mL of water, and slowly add this solution, with

bromocresol green and 0.1 g of methyl red in 180 mL of constant stirring, to the first solution. Cool the mixture, addalcohol, and dilute with water to 200 mL. water to make 1000 mL, and mix.

Bromocresol Purple TS—Dissolve 250 mg of bromo- Cupric Citrate TS 2, Alkaline—With the aid of heat, dis-cresol purple in 20 mL of 0.05 N sodium hydroxide, and solve about 173 g of sodium citrate dihydrate and 117 g ofdilute with water to 250 mL. sodium carbonate monohydrate in about 700 mL of water,

Bromophenol Blue TS—Dissolve 100 mg of bromophe- and filter. In a second flask, dissolve about 27.06 g of cupricnol blue in 100 mL of diluted alcohol, and filter if necessary. sulfate (CuSO4 · 5H2O) in about 100 mL of water. Slowly

Bromothymol Blue TS—Dissolve 100 mg of combine the two solutions while stirring, and dilute withbromothymol blue in 100 mL of diluted alcohol, and filter if water to 1000 mL.necessary. Cupric Iodide TS, Alkaline—Dissolve 7.5 g of cupric sul-

Buffered Acetone TS—See Acetone, Buffered, TS. fate (CuSO4 · 5H2O) in about 100 mL of water. In a separateCalcium Chloride TS—Dissolve 7.5 g of calcium chloride container dissolve 25 g of anhydrous sodium carbonate,

in water to make 100 mL. 20 g of sodium bicarbonate, and 25 g of potassium sodiumCalcium Hydroxide TS—Use Calcium Hydroxide Topical tartrate in about 600 mL of water. With constant stirring,

Solution (USP monograph). add the cupric sulfate solution to the bottom of the alkalineCalcium Sulfate TS—A saturated solution of calcium sul- tartrate solution by means of a funnel that touches the bot-

fate in water. tom of the container. Add 1.5 g of potassium iodide, 200 gCeric Ammonium Nitrate TS—Dissolve 6.25 g of ceric of anhydrous sodium sulfate, 50 to 150 mL of 0.02 M po-

ammonium nitrate in 10 mL of 0.25 N nitric acid. Use tassium iodate, and sufficient water to make 1000 mL.within 3 days. Cupric Oxide, Ammoniated, TS (Schweitzer’s Reagent)—

Chloral Hydrate TS—Dissolve 50 g of chloral hydrate in Dissolve 10 g of cupric sulfate in 100 mL of water, add suffi-a mixture of 15 mL of water and 10 mL of glycerin. cient sodium hydroxide solution (1 in 5) to precipitate the

Chlorine TS (Chlorine Water)—A saturated solution of copper hydroxide, collect the latter on a filter, and washchlorine in water. Place the solution in small, completely free from sulfate with cold water. Dissolve the precipitate,filled, light-resistant containers. Chlorine TS, even when kept which must be kept wet during the entire process, in thefrom light and air, is apt to deteriorate. Store it in a cold, minimum quantity of ammonia TS necessary for completedark place. For full strength, prepare this solution fresh. solution.

Chromotropic Acid TS—Dissolve 50 mg of chromotropic Cupric Sulfate TS—Dissolve 12.5 g of cupric sulfate inacid or its disodium salt in 100 mL of 75% sulfuric acid, water to make 100 mL.which may be made by cautiously adding 75 mL of sulfuric Cupric Tartrate TS, Alkaline (Fehling’s Solution)—acid to 33.3 mL of water. The Copper Solution (A)—Dissolve 34.66 g of carefully se-

Cobalt–Uranyl Acetate TS—Dissolve, with warming, lected, small crystals of cupric sulfate, showing no trace of40 g of uranyl acetate in a mixture of 30 g of glacial acetic efflorescence of adhering moisture, in water to makeacid and sufficient water to make 500 mL. Similarly, prepare 500 mL. Store this solution in small, tight containers.a solution containing 200 g of cobaltous acetate in a mix- The Alkaline Tartrate Solution (B)—Dissolve 173 g of crys-ture of 30 g of glacial acetic acid and sufficient water to tallized potassium sodium tartrate and 50 g of sodium hy-make 500 mL. Mix the two solutions while still warm, and droxide in water to make 500 mL. Store this solution incool to 20°. Maintain the temperature at 20° for about small, alkali-resistant containers.2 hours to separate the excess salts from solution, and then For use, mix exactly equal volumes of Solutions A and B atpass through a dry filter. the time required.


Delafield’s Hematoxylin TS—Prepare 400 mL of a satu- Fehling’s Solution—See Cupric Tartrate TS, Alkaline.rated solution of ammonium alum (Solution A). Dissolve 4 g Ferric Ammonium Sulfate TS—Dissolve 8 g of ferric am-of hematoxylin in 25 mL of alcohol, mix it with Solution A, monium sulfate in water to make 100 mL.and allow it to stand for 4 days in a flask closed with a Ferric Chloride TS—Dissolve 9 g of ferric chloride inpledget of purified cotton and exposed to light and air (So- water to make 100 mL.lution B). Then filter Solution B, and add to it a Solution C Ferroin TS—Dissolve 0.7 g of ferrous sulfate and 1.76 gconsisting of a mixture of 100 mL of glycerin and 100 mL of of o-phenanthroline monohydrochloride monohydrate inmethanol. Mix, and allow the mixture to stand in a warm water, and dilute with water to 100 mL.place, exposed to light, for 6 weeks until it becomes dark- Ferrous Sulfate TS—Dissolve 8 g of clear crystals of fer-colored. Store in tightly stoppered bottles. rous sulfate in about 100 mL of recently boiled and thor-

For use in staining endocrine tissue, dilute this test solu- oughly cooled water. Prepare this solution fresh.tion with an equal volume of water. Ferrous Sulfate, Acid, TS—Dissolve 7 g of ferrous sulfate

Denaturated Alcoholic TS—A specially denaturated alco- crystals in 90 mL of recently boiled and thoroughly cooledhol containing either rubber hydrocarbon solvent of hep- water, and add sulfuric acid to make 100 mL. Prepare thistane or toluene. [NOTE—A suitable grade is available from solution immediately prior to use.www.lyondell.com or from www.sasol.com, as Ethanol SDA Folin-Ciocalteu Phenol TS—Into a 1500-mL flask intro-2B HEP 200, or Ethanol SDA 2B TOL 200, or Ethanol SDA duce 100 g of sodium tungstate, 25 g of sodium molybdate,2B TOL 190, or Alcohol SDA 2B-2.] 700 mL of water, 50 mL of phosphoric acid, and 100 mL of

Deniges’ Reagent—See Mercuric Sulfate TS. hydrochloric acid. Gently reflux the mixture for aboutDiazobenzenesulfonic Acid TS—Place in a beaker 1.57 g 10 hours, and add 150 g of lithium sulfate, 50 mL of water,

of sulfanilic acid, previously dried at 105° for 3 hours, add and a few drops of bromine. Boil the mixture, without the80 mL of water and 10 mL of diluted hydrochloric acid, and condenser, for about 15 minutes, or until the excess bro-warm on a steam bath until dissolved. Cool to 15° (some of mine is expelled. Cool, dilute with water to 1 L, and filter:the sulfanilic acid may separate but will dissolve later), and the filtrate has no greenish tint. Before use, dilute 1 part ofadd slowly, with constant stirring, 6.5 mL of sodium nitrite the filtrate with 1 part of water. When used for protein de-solution (1 in 10). Then dilute with water to 100 mL. termination (i.e., Lowry assay), this reagent must be further

Dichlorofluorescein TS—Dissolve 100 mg of dichloro- diluted (1:5) with water. See Method 2 in Total Protein Assayfluorescein in 60 mL of alcohol, add 2.5 mL of 0.1 N sodium under Biotechnology-Derived Articles—Total Protein Assayhydroxide, mix, and dilute with water to 100 mL. ⟨1057⟩.

2,7-Dihydroxynaphthalene TS—Dissolve 100 mg of 2,7- Formaldehyde TS—Use Formaldehyde Solution (see in thedihydroxynaphthalene in 1000 mL of sulfuric acid, and allow section Reagents).the solution to stand until the yellow color disappears. If the Fuchsin–Pyrogallol TS—Dissolve 100 mg of basic fuchsinsolution is very dark, discard it and prepare a new solution in 50 mL of water that previously has been boiled forfrom a different supply of sulfuric acid. This solution is stable 15 minutes and allowed to cool slightly. Cool, add 2 mL offor approximately 1 month if stored in a dark bottle. a saturated solution of sodium bisulfite, mix, and allow to

Diiodofluorescein TS—Dissolve 500 mg of stand for not less than 3 hours. Add 0.9 mL of hydrochloricdiiodofluorescein in a mixture of 75 mL of alcohol and acid, mix, and allow to stand overnight. Add 100 mg of30 mL of water. pyrogallol, shake until solution is effected, and dilute with

Diluted Lead Subacetate TS—See Lead Subacetate TS, water to 100 mL. Store in an amber-colored glass bottle in aDiluted. refrigerator.

p-Dimethylaminobenzaldehyde TS—Dissolve 125 mg of Fuchsin–Sulfurous Acid TS—Dissolve 200 mg of basicp-dimethylaminobenzaldehyde in a cooled mixture of 65 mL fuchsin in 120 mL of hot water, and allow the solution toof sulfuric acid and 35 mL of water, and add 0.05 mL of cool. Add a solution of 2 g of anhydrous sodium sulfite inferric chloride TS. Use within 7 days. 20 mL of water, then add 2 mL of hydrochloric acid. Dilute

Dinitrophenylhydrazine TS—Carefully mix 10 mL of the solution with water to 200 mL, and allow to stand for atwater and 10 mL of sulfuric acid, and cool. To the mixture, least 1 hour. Prepare this solution fresh.contained in a glass-stoppered flask, add 2 g of 2,4-dini- Gastric Fluid, Simulated, TS—Dissolve 2.0 g of sodiumtrophenylhydrazine, and shake until dissolved. To the solu- chloride and 3.2 g of purified pepsin, that is derived fromtion add 35 mL of water, mix, cool, and filter. porcine stomach mucosa, with an activity of 800 to 2500

Diphenylamine TS—Dissolve 1.0 g of diphenylamine in units per mg of protein, in 7.0 mL of hydrochloric acid and100 mL of sulfuric acid. The solution should be colorless. sufficient water to make 1000 mL. [NOTE—Pepsin activity is

Diphenylcarbazone TS—Dissolve 1 g of crystalline described in the Food Chemicals Codex specifications underdiphenylcarbazone in 75 mL of alcohol, then add alcohol to General Tests and Assays.] This test solution has a pH ofmake 100 mL. Store in a brown bottle. about 1.2.

Dithizone TS—Dissolve 25.6 mg of dithizone in 100 mL Gelatin TS (for the assay of Corticotropin Injection)—Dis-of alcohol. Store in a cold place, and use within 2 months. solve 340 g of acid-treated precursor gelatin (Type A) in

Dragendorff’s TS—Mix 850 mg of bismuth subnitrate water to make 1000 mL. Heat the solution in an autoclavewith 40 mL of water and 10 mL of glacial acetic acid (Solu- at 115° for 30 minutes after the exhaust line temperaturetion A). Dissolve 8 g of potassium iodide in 20 mL of water has reached 115°. Cool the solution, and add 10 g of phe-(Solution B). Mix equal portions of Solution A and Solution B nol and 1000 mL of water. Store in tight containers in ato obtain a stock solution, which can be stored for several refrigerator.months in a dark bottle. Mix 10 mL of the stock solution Glacial Acetic Acid TS—See Acetic Acid, Glacial, TS.with 20 mL of glacial acetic acid, and dilute with water to Glucose Oxidase–Chromogen TS—A solution contain-make 100 mL. ing, in each mL, 0.5 µmol of 4-aminoantipyrine, 22.0 µmol

Edetate Disodium TS—Dissolve 1 g of edetate disodium of sodium p-hydroxybenzoate, not less than 7.0 units of glu-in 950 mL of water, add 50 mL of alcohol, and mix. cose oxidase, and not less than 0.5 units of peroxidase, and

Eosin Y TS (adsorption indicator)—Dissolve 50 mg of eo- buffered to a pH of 7.0 ± 0.1.sin Y in 10 mL of water. Suitability—When used for determining glucose in Inulin,

Eriochrome Black TS—Dissolve 200 mg of eriochrome ascertain that no significant color results by reaction withblack T and 2 g of hydroxylamine hydrochloride in metha- fructose, and that a suitable absorbance-versus-concentra-nol to make 50 mL. tion slope is obtained with glucose.

Eriochrome Cyanine TS—Dissolve 750 mg of eriochrome [NOTE—A suitable grade is available, as a concentrate,cyanine R in 200 mL of water, add 25 g of sodium chloride, from Worthington Diagnostics, Division of Millipore Corp.,25 g of ammonium nitrate, and 2 mL of nitric acid, and di- www.millipore.com.]lute with water to 1000 mL.


Glycerin Base TS—To 200 g of glycerin add water to Iron–Phenol TS (Iron-Kober Reagent)—Dissolve 1.054 g ofbring the total weight to 235 g. Add 140 mL of 1 N sodium ferrous ammonium sulfate in 20 mL of water, and add 1 mLhydroxide and 50 mL of water. of sulfuric acid and 1 mL of 30 percent hydrogen peroxide.

Gold Chloride TS—Dissolve 1 g of gold chloride in Mix, heat until effervescence ceases, and dilute with water35 mL of water. to 50 mL. To 3 volumes of this solution contained in a volu-

Hydrogen Peroxide TS—Use Hydrogen Peroxide Topical metric flask add sulfuric acid, with cooling, to make 100Solution (USP monograph). volumes. Purify phenol by distillation, discarding the first

Hydrogen Sulfide TS—A saturated solution of hydrogen 10% and the last 5%, collecting the distillate, with exclusionsulfide, made by passing H2S into cold water. Store it in of moisture, in a dry, tared glass-stoppered flask of aboutsmall, dark amber-colored bottles, filled nearly to the top. It twice the volume of the phenol. Solidify the phenol in anis unsuitable unless it possesses a strong odor of H2S, and ice bath, breaking the top crust with a glass rod to ensureunless it produces at once a copious precipitate of sulfur complete crystallization. Weigh the flask and its contents,when added to an equal volume of ferric chloride TS. Store add to the phenol 1.13 times its weight of the iron–sulfuricin a cold, dark place. acid solution prepared as directed, insert the stopper in the

Hydroxylamine Hydrochloride TS—Dissolve 3.5 g of hy- flask, and allow to stand, without cooling but with occa-droxylamine hydrochloride in 95 mL of 60% alcohol, and sional mixing, until the phenol is liquefied. Shake the mix-add 0.5 mL of bromophenol blue solution (1 in 1000 of ture vigorously until mixed, allow to stand in the dark foralcohol) and 0.5 N alcoholic potassium hydroxide until a 16 to 24 hours, and again weigh the flask and its contents.greenish tint develops in the solution. Then add 60% alco- To the mixture add 23.5% of its weight of a solution of 100hol to make 100 mL. volumes of sulfuric acid in 110 volumes of water, mix, trans-

8-Hydroxyquinoline TS—Dissolve 5 g of 8-hydroxy- fer to dry glass-stoppered bottles, and store in the dark,quinoline in alcohol to make 100 mL. protected from atmospheric moisture. Use within 6 months.

Indigo Carmine TS (Sodium Indigotindisulfonate TS)—Dis- Dispense the reagent from a small-bore buret, arranged tosolve a quantity of sodium indigotindisulfonate, equivalent exclude moisture, capable of delivering 1 mL in 30 secondsto 180 mg of C16H8N2O2(SO3Na)2, in water to make 100 mL. or less, and having no lubricant, other than reagent, on itsUse within 60 days. stopcock. Wipe the buret tip with tissue before each addi-

Indophenol–Acetate TS (for the assay of Corticotropin In- tion.jection)—To 60 mL of standard dichlorophenol-indophenol Iron Salicylate TS—Dissolve 500 mg of ferric ammoniumsolution (see in the section Volumetric Solutions) add water sulfate in 250 mL of water containing 10 mL of diluted sul-to make 250 mL. Add to the resulting solution an equal vol- furic acid, and add water to make 500 mL. To 100 mL ofume of sodium acetate solution freshly prepared by dissolv- the resulting solution add 50 mL of a 1.15% solution of so-ing 13.66 g of anhydrous sodium acetate in water to make dium salicylate, 20 mL of diluted acetic acid, and 80 mL of a500 mL and adjusting with 0.5 N acetic acid to a pH of 7. 13.6% solution of sodium acetate, then add water to makeStore in a refrigerator, and use within 2 weeks. 500 mL. Store in a well-closed container. Protect from light.

Intestinal Fluid, Simulated, TS—Dissolve 6.8 g of mono- Use within 2 weeks.basic potassium phosphate in 250 mL of water, mix, and Lanthanum Nitrate TS—Dissolve 5.0 g of lanthanum ni-add 77 mL of 0.2 N sodium hydroxide and 500 mL of trate hexahydrate in 100 mL of water.water. Add 10.0 g of pancreatin, mix, and adjust the result- Lead Acetate TS—Dissolve 9.5 g of clear, transparenting solution with either 0.2 N sodium hydroxide or 0.2 N crystals of lead acetate in recently boiled water to makehydrochloric acid to a pH of 6.8 ± 0.1. Dilute with water to 100 mL. Store in well-stoppered bottles.1000 mL. Lead Acetate TS, Alcoholic—Dissolve 2 g of clear, trans-

Iodine TS—Use 0.1 N Iodine (see in the section Volumet- parent crystals of lead acetate in alcohol to make 100 mL.ric Solutions). Store in tight containers.

Iodine, Diluted TS—Transfer 10.0 mL of 0.1 N iodine VS Lead Subacetate TS—Dissolve 40.0 g of lead acetate into a 100-mL volumetric flask, dilute with water to volume, 90 mL of carbon dioxide-free water. Adjust with 10 M so-and mix. dium hydroxide to a pH of 7.5, centrifuge, and use the clear

Iodine Monochloride TS—Dissolve 10 g of potassium io- supernatant. It contains NLT 16.7% (w/w) and NMT 17.4%dide and 6.44 g of potassium iodate in 75 mL of water in a (w/w) of Pb in a form corresponding to the formulaglass-stoppered container. Add 75 mL of hydrochloric acid C8H14O10Pb3. The solution remains clear when stored in aand 5 mL of chloroform, and adjust to a faint iodine color well-closed container.(in the chloroform) by adding dilute potassium iodide or Lead Subacetate TS, Diluted—Dilute 3.25 mL of leadpotassium iodate solution. If much iodine is liberated, use a subacetate TS with water, recently boiled and cooled, tostronger solution of potassium iodate than 0.01 M at first, make 100 mL. Store in small, well-filled, tight containers.making the final adjustment with the 0.01 M potassium io- Litmus TS—Digest 25 g of powdered litmus with threedate. Store in a dark place, and readjust to a faint iodine successive 100-mL portions of boiling alcohol, continuingcolor as necessary. each extraction for about 1 hour. Filter, wash with alcohol,

Iodine and Potassium Iodide TS 1—Dissolve 500 mg of and discard the alcohol filtrate. Macerate the residue withiodine and 1.5 g of potassium iodide in 25 mL of water. about 25 mL of cold water for 4 hours, filter, and discard

Iodine and Potassium Iodide TS 2—Dissolve 12.7 g of the filtrate. Finally digest the residue with 125 mL of boilingiodine and 20 g of potassium iodide in water, and dilute water for 1 hour, cool, and filter.with water to 1000.0 mL. To 10.0 mL of this solution, add Locke-Ringer’s Solution—See Locke-Ringer’s TS.0.6 g of potassium iodide, and dilute with water to Locke-Ringer’s TS (Locke-Ringer’s Solution)—100.0 mL. Prepare immediately before use.

Iodine and Potassium Iodide TS 3—Dissolve 0.127 g ofiodine and 0.20 g of potassium iodide in water, and dilute

Sodium Chloride 9.0 gwith water to 10.0 mL.Potassium Chloride 0.42 gIodobromide TS—Dissolve 20 g of iodine monobromideCalcium Chloride 0.24 gin glacial acetic acid to make 1000 mL. Store in glass con-

tainers, protected from light. Magnesium Chloride 0.2 gIodochloride TS—Dissolve 16.5 g of iodine monochlo- Sodium Bicarbonate 0.5 g

ride in 1000 mL of glacial acetic acid. Dextrose 0.5 gIodoplatinate TS—Dissolve 300 mg of platinic chloride

Water, recently distilled from a hard-glassin 97 mL of water. Immediately prior to use, add 3.5 mL offlask, a sufficient quantity to make 1000 mLpotassium iodide TS, and mix.


Prepare fresh each day. The constituents (except the dex- Methyl Red TS 2—To 1.86 mL of 0.1 M sodium hydrox-trose and the sodium bicarbonate) may be made up in ide and 50 mL of alcohol, add 50 mg of methyl red, andstock solutions and diluted as needed. dilute with water to 100 mL.

Magnesia Mixture TS—Dissolve 5.5 g of magnesium Methyl Red TS, Methanolic—Dissolve 1 g of methyl redchloride and 7 g of ammonium chloride in 65 mL of water, in 100 mL of methanol, and filter, if necessary. Store pro-add 35 mL of ammonia TS, set the mixture aside for a few tected from light, and use within 21 days.days in a well-stoppered bottle, and filter. If the solution is Methyl Red–Methylene Blue TS—Add 10 mL of methylnot perfectly clear, filter it before using. red TS to 10 mL of methylene blue TS, and mix.

Magnesium Sulfate TS—Dissolve 12 g of crystals of Methyl Violet TS—Use Crystal Violet TS.magnesium sulfate, selected for freedom from efflorescence, Methyl Yellow TS—Prepare a solution containingin water to make 100 mL. 0.10 mg per mL in alcohol.

Malachite Green TS—Dissolve 1 g of malachite green Methyl Yellow–Methylene Blue TS—Dissolve 1 g ofoxalate in 100 mL of glacial acetic acid. methyl yellow and 100 mg of methylene blue in 125 mL of

Mallory’s Stain—Dissolve 500 mg of water-soluble ani- methanol.line blue, 2 g of orange G, and 2 g of oxalic acid in 100 mL 3-Methyl-2-benzothiazolinone Hydrazoneof water. Hydrochloride TS—Dissolve 0.1 g of 3-methyl-2-benzo-

Mayer’s Reagent—See Mercuric–Potassium Iodide TS. thiazolinone hydrazone hydrochloride monohydrate inMercuric Acetate TS—Dissolve 6.0 g of mercuric acetate 10 mL of water, dilute the resulting solution with methanol

in glacial acetic acid to make 100 mL. Store in tight contain- to 100 mL, and mix.ers, protected from direct sunlight. Methylene Blue TS—Dissolve 125 mg of methylene blue

Mercuric–Ammonium Thiocyanate TS—Dissolve 30 g of in 100 mL of alcohol, and dilute with alcohol to 250 mL.ammonium thiocyanate and 27 g of mercuric chloride in Methylthionine Perchlorate TS—To 500 mL of potas-water to make 1000 mL. sium perchlorate solution (1 in 1000) add dropwise, with

Mercuric Bromide TS, Alcoholic—Dissolve 5 g of mercu- constant shaking, methylene blue solution (1 in 100) until aric bromide in 100 mL of alcohol, employing gentle heat to slight, permanent turbidity results. Allow the precipitate tofacilitate solution. Store in glass containers, protected from settle, decant the supernatant through paper, and use onlylight. the clear solution.

Mercuric Chloride TS—Dissolve 6.5 g of mercuric chlo- Millon’s Reagent—To 2 mL of mercury in a conical flaskride in water to make 100 mL. add 20 mL of nitric acid. Shake the flask under a hood to

Mercuric Iodide TS (Valser’s Reagent)—Slowly add potas- break up the mercury into small globules. After aboutsium iodide solution (1 in 10) to red mercuric iodide until 10 minutes, add 35 mL of water, and, if a precipitate oralmost all of the latter is dissolved, and filter off the excess. crystals appear, add sufficient dilute nitric acid (1 in 5, pre-A solution containing 10 g of potassium iodide in 100 mL pared from nitric acid from which the oxides have beendissolves approximately 14 g of HgI2 at 20°. removed by blowing air through it until it is colorless) to

Mercuric Nitrate TS—Dissolve 40 g of mercuric oxide dissolve the separated solid. Add sodium hydroxide solution(red or yellow) in a mixture of 32 mL of nitric acid and (1 in 10) dropwise, with thorough mixing, until the curdy15 mL of water. Store in glass containers, protected from precipitate that forms after the addition of each drop nolight. longer redissolves but is dispersed to form a suspension.

Mercuric–Potassium Iodide TS (Mayer’s Reagent)—Dis- Add 5 mL more of the dilute nitric acid, and mix. Preparesolve 1.358 g of mercuric chloride in 60 mL of water. Dis- this solution fresh.solve 5 g of potassium iodide in 10 mL of water. Mix the Molybdo-phosphotungstate TS (Folin-Denis Reagent)—two solutions, and dilute with water to 100 mL. To about 350 mL of water contained in a round-bottom

Mercuric–Potassium Iodide TS, Alkaline (Nessler’s flask add 50 g of sodium tungstate, 12 g of phosphomolyb-Reagent)—Dissolve 143 g of sodium hydroxide in 700 mL of dic acid, and 25 mL of phosphoric acid. Boil the mixturewater. Dissolve 50 g of red mercuric iodide and 40 g of po- under a reflux condenser for 2 hours, then cool, dilute withtassium iodide in 200 mL of water. Pour the iodide solution water to 500 mL, and mix. Store in tight containers, pro-into the hydroxide solution, and dilute with water to tected from light, and in a cold place.1000 mL. Allow to settle, and use the clear supernatant. 1-Naphthol Reagent—Dissolve 1 g of 1-naphthol in

Mercuric Sulfate TS (Deniges’ Reagent)—Mix 5 g of yel- 25 mL of methanol. Prepare this solution fresh.low mercuric oxide with 40 mL of water, and while stirring 1-Naphthol TS—Use 1-Naphthol Reagent.slowly add 20 mL of sulfuric acid, then add another 40 mL 2-Naphthol TS (Betanaphthol TS)—Dissolve 1 g ofof water, and stir until completely dissolved. 2-naphthol in 100 mL of sodium hydroxide solution (1 in

Mercurous Nitrate TS—Dissolve 15 g of mercurous ni- 100).trate in a mixture of 90 mL of water and 10 mL of diluted p-Naphtholbenzein TS—Dissolve 250 mg of p-naphthol-nitric acid. Store in dark, amber-colored bottles in which a benzein in 100 mL of glacial acetic acid.small globule of mercury has been placed. N-(1-Naphthyl)ethylenediamine Dihydrochloride TS—

Metaphenylenediamine Hydrochloride TS—Dissolve 1 g Dissolve 100 mg of N-(1-naphthyl)ethylenediamine dihydro-of metaphenylenediamine hydrochloride in 200 mL of chloride in 100 mL of a mixture of 7 parts of acetone andwater. The solution must be colorless when used. If neces- 3 parts of water.sary, decolorize by heating with activated charcoal. Nessler’s Reagent—See Mercuric–Potassium Iodide TS, Al-

Metaphosphoric–Acetic Acids TS—Dissolve 15 g of met- kaline.aphosphoric acid in 40 mL of glacial acetic acid and suffi- Neutral Red TS—Dissolve 100 mg of neutral red incient water to make 500 mL. Store in a cold place, and use 100 mL of 50% alcohol.within 2 days. Nickel Standard Solution TS—Dissolve 4.78 g of

Methoxyphenylacetic TS—Dissolve 2.7 g of methoxy- nickel (II) sulfate heptahydrate in water, and dilute withphenylacetic acid in 6 mL of Tetramethylammonium Hydrox- water to 1000 mL. Immediately prior to use, dilute 10.0 mLide TS, and add 20 mL of dehydrated alcohol. Store in a of the solution so obtained with water to 1000 mL. Suitablepolyethylene container. nickel standard solutions are also available commercially.

Methyl Orange TS—Dissolve 100 mg of methyl orange Ninhydrin TS—Use Triketohydrindene Hydrate TS.in 100 mL of water, and filter if necessary. p-Nitroaniline TS—To 350 mg of p-nitroaniline add

Methyl Purple TS—Use Methyl Red–Methylene Blue TS. 1.5 mL of hydrochloric acid, and mix. Dilute with water toMethyl Red TS—Dissolve 100 mg of methyl red in 50 mL, mix, and allow to settle. Place 5 mL of the clear

100 mL of alcohol, and filter if necessary. supernatant in a 100-mL volumetric flask, and immerse it inan ice bath. While it is in the ice bath, add 1 mL of hydro-chloric acid, then add, in small portions, 2 mL of sodium


nitrite solution (1 in 100), dilute with water to volume, and Potassium Acetate TS—Dissolve 10 g of potassium ace-mix. tate in water to make 100 mL.

Nitrophenanthroline TS—Dissolve 150 mg of 5-nitro- Potassium–Bismuth Iodide TS—Dissolve 12.5 g of tar-1,10-phenanthroline in 15 mL of freshly prepared ferrous taric acid in 25 mL of water, then dissolve 1.06 g of bismuthsulfate solution (1 in 140). subnitrate in this mixture (Solution A). Dissolve 20 g of po-

Oracet Blue B TS—A 1 in 200 solution of oracet blue B tassium iodide in 25 mL of water (Solution B). Dissolve 100 gin glacial acetic acid. of tartaric acid in 450 mL of water (Solution C). Add Solu-

Orthophenanthroline TS—Dissolve 150 mg of tions A and B to Solution C, and mix.orthophenanthroline in 10 mL of a solution of ferrous sul- Potassium Carbonate TS—Dissolve 7 g of anhydrous po-fate, prepared by dissolving 700 mg of clear crystals of fer- tassium carbonate in water to make 100 mL.rous sulfate in 100 mL of water. The ferrous sulfate solution Potassium Chromate TS—Dissolve 10 g of potassiummust be prepared immediately before dissolving the chromate in water to make 100 mL.orthophenanthroline. Store in well-closed containers. Potassium Dichromate TS—Dissolve 7.5 g of potassium

Oxalic Acid TS—Dissolve 6.3 g of oxalic acid in water to dichromate in water to make 100 mL.make 100 mL. Potassium Ferricyanide TS—Dissolve 1 g of potassium

Palladium Chloride TS, Buffered—Weigh 500 mg of pal- ferricyanide in 10 mL of water. Prepare this solution fresh.ladium chloride into a 250-mL beaker, add 5 mL of concen- Potassium Ferrocyanide TS—Dissolve 1 g of potassiumtrated hydrochloric acid, and warm the mixture on a steam ferrocyanide in 10 mL of water. Prepare this solution fresh.bath. Add 200 mL of hot water in small increments with Potassium Hydroxide TS—Dissolve 6.5 g of potassiumcontinued heating until solution is complete. Transfer the hydroxide in water to make 100 mL.solution to a 250-mL volumetric flask, and dilute with water Potassium Hydroxide TS, Alcoholic—Use 0.5 N Potas-to volume. Transfer 50 mL to a 100-mL volumetric flask. sium Hydroxide, Alcoholic (see in the section Volumetric Solu-Add 10 mL of 1 M sodium acetate and 9.6 mL of 1 N hydro- tions).chloric acid. Dilute with water to volume. Potassium Hydroxide TS 2, Alcoholic—Dissolve 130 g of

Perchloric Acid TS—Dilute 8.5 mL of perchloric acid with potassium hydroxide, with cooling, in 200 mL of water. Addwater to 100 mL. alcohol to 1000 mL. Store in a well-stoppered dark glass

Phenol TS—Dissolve 1.2 g of phenol in alcohol to make bottle.10 mL. Prepare weekly. Potassium Iodide TS—Dissolve 16.5 g of potassium io-

Phenol Red TS (Phenolsulfonphthalein TS)—Dissolve dide in water to make 100 mL. Store in light-resistant con-100 mg of phenolsulfonphthalein in 100 mL of alcohol, and tainers.filter if necessary. Potassium Iodide and Starch TS—Dissolve 0.75 g of po-

pH 4.7 Phenol Red TS—Dissolve 33 mg of phenolsulfon- tassium iodide in 100 mL of water. Heat to boiling, andphthalein in 1.5 mL of 2 N sodium hydroxide solution, di- add, with stirring, a solution of 0.5 g of soluble starch inlute with water to 100 mL, and mix (Solution A). Dissolve 35 mL of water. Boil for 2 minutes, and allow to cool.25 mg of ammonium sulfate in 235 mL of water, add Sensitivity—Mix 15 mL in 0.05 mL of glacial acetic acid105 mL of 2 N sodium hydroxide solution and 135 mL of and 0.3 mL of diluted iodine TS: a blue color is produced.2 N acetic acid, and mix (Solution B). Add 25 mL of Solution Potassium Iodoplatinate TS—Dissolve 200 mg of pla-A to Solution B, and mix. If necessary, adjust the pH of this tinic chloride in 2 mL of water, mix with 25 mL of potas-solution to 4.7. sium iodide solution (1 in 25), and add water to make

Phenoldisulfonic Acid TS—Dissolve 2.5 g of phenol in 50 mL.15 mL of sulfuric acid in a flask of suitable capacity. Add Potassium Permanganate TS—Use 0.1 N Potassium Per-7.5 mL of fuming sulfuric acid, stir well, and heat at 100° manganate (see in the section Volumetric Solutions).for 2 hours. Transfer the product, while still fluid, to a glass- Potassium Pyroantimonate TS—Dissolve 2 g of potas-stoppered bottle, and, when desired for use, warm in a sium pyroantimonate in 85 mL of hot water. Cool quickly,water bath until liquefied. and add 50 mL of a solution containing 50 mg/mL of potas-

Phenolphthalein TS—Dissolve 1 g of phenolphthalein in sium hydroxide in water and 1 mL of sodium hydroxide so-100 mL of alcohol. lution (8.5 in 100). Allow to stand for 24 h, filter, and dilute

Phenylhydrazine Acetate TS—Dissolve 10 mL of phenyl- with water to 150 mL.hydrazine and 5 mL of glacial acetic acid in water to make Potassium Sulfate TS—Dissolve 1 g of potassium sulfate100 mL. in water to make 100 mL.

Phenylhydrazine–Sulfuric Acid TS—Dissolve 65 mg of Potassium Thiocyanate TS—Dissolve 9.7 g of potassiumphenylhydrazine hydrochloride in 100 mL of a cooled mix- thiocyanate in water to make 100 mL.ture of equal volumes of sulfuric acid and water. Pyridine–Pyrazolone TS—To 100 mL of a saturated solu-

Phloroglucinol TS—Dissolve 500 mg of phloroglucinol in tion of 1-phenyl-3-methyl-2-pyrazoline-5-one add 20 mL of25 mL of alcohol. Store in tight containers, protected from a 1 in 1000 solution of 3,3′-dimethyl-1,1′-diphenyl-[4,4′-bi-light. 2-pyrazoline]-5,5′-dione in pyridine. Store in a dark bottle,

Phosphatic Enzyme TS—Dissolve 5 g of phosphatic en- and use within 3 days.zyme in water to make 50 mL. Prepare this solution fresh. Pyrogallol TS, Alkaline—Dissolve 500 mg of pyrogallol

Phosphomolybdic Acid TS—Dissolve 20 g of phospho- in 2 mL of water. Dissolve 12 g of potassium hydroxide inmolybdic acid in alcohol to make 100 mL. Filter the solu- 8 mL of water. The solutions should be freshly prepared andtion, and use only the clear filtrate. mixed immediately before use.

Phosphotungstic Acid TS—Dissolve 1 g of phosphotung- Quinaldine Red TS—Dissolve 100 mg of quinaldine redstic acid in water to make 100 mL. in 100 mL of alcohol.

Picrate TS, Alkaline—Mix 20 mL of trinitrophenol solu- Quinone TS—Dissolve 500 mg of p-benzoquinone intion (1 in 100) with 10 mL of sodium hydroxide solution (1 2.5 mL of glacial acetic acid, and dilute with alcohol toin 20), dilute with water to 100 mL, and mix. Use within 2 50 mL. Prepare this solution fresh daily.days. Resorcinol TS—Dissolve 1 g of resorcinol in hydrochloric

Picric Acid TS—See Trinitrophenol TS. acid to make 100 mL.Platinic Chloride TS—Dissolve 2.6 g of platinic chloride Ruthenium Red TS—Dissolve 10 g of lead acetate in

in water to make 20 mL. water, dilute with water to 100 mL, and add 80 mg of ru-Platinum–Cobalt TS—Dissolve 1.246 g of potassium thenium red. The solution is wine-red in color. [NOTE—If

chloroplatinate (K2PtCl6) and 1.000 g of cobalt chloride necessary, add additional ruthenium red to obtain a wine-(CoCl2 · 6H2O) in water, add 100 mL of hydrochloric acid, red color.]and dilute with water to 1 L.


Saline TS—Dissolve 9.0 g of sodium chloride in water to Sodium Hypochlorite TS—Use Sodium Hypochlorite Solu-make 1000 mL. tion (see in the section Reagent Specifications).

[NOTE—Where pyrogen-free saline TS is specified in this Sodium Iodohydroxyquinolinesulfonate TS—DissolvePharmacopeia, saline TS that has met the requirements of 8.8 g of iodohydroxyquinoline sulfonic acid in 200 mL ofthe Pyrogen Test ⟨151⟩ is to be used.] water, and add 6.5 mL of 4 N sodium hydroxide. Dilute

Saline TS, Pyrogen-Free—See Saline TS. with water to 250 mL, mix, and filter.Schweitzer’s Reagent—See Cupric Oxide, Ammoniated, Sodium Nitroferricyanide TS—Dissolve 1 g of sodium

TS. nitroferricyanide in water to make 20 mL. Prepare this solu-Silver–Ammonia–Nitrate TS—Dissolve 1 g of silver ni- tion fresh.

trate in 20 mL of water. Add ammonia TS, dropwise, with Dibasic Sodium Phosphate TS—Dissolve 12 g of dibasicconstant stirring, until the precipitate is almost but not en- sodium phosphate in water to make 100 mL.tirely dissolved. Filter, and store in tight, light-resistant con- Sodium Phosphotungstate TS—To a solution of 20 g oftainers. sodium tungstate in 100 mL of water add sufficient phos-

Silver–Ammonium Nitrate TS—See Silver–Ammonia– phoric acid to impart a strongly acid reaction to litmus, andNitrate TS. filter. When required for use, decant the clear solution from

Silver Diethyldithiocarbamate TS—Dissolve 1 g of silver any sediment that may be present. Store in tight, light-resis-diethyldithiocarbamate in 200 mL of pyridine from a freshly tant containers.opened bottle or that which has been recently distilled. Sodium Sulfide TS—Dissolve 1 g of sodium sulfide inStore in light-resistant containers, and use within 30 days. water to make 10 mL. Prepare this solution fresh.

Silver Nitrate TS—Use 0.1 N Silver Nitrate (see in the Sodium Tartrate TS—Dissolve 11.5 g of sodium tartratesection Volumetric Solutions). in water to make 100 mL.

Simulated Gastric Fluid TS—See Gastric Fluid, Simulated, Sodium Tetraphenylboron TS—Dissolve 1.2 g of sodiumTS. tetraphenylboron in water to make 200 mL. If necessary, stir

Simulated Intestinal Fluid TS—See Intestinal Fluid, Simu- for 5 minutes with 1 g of aluminum oxide, and filter to clar-lated, TS. ify.

Sodium Acetate TS—Dissolve 13.6 g of sodium acetate Sodium Thioglycolate TS—Dissolve 1.5 g of sodium thi-in water to make 100 mL. oglycolate in 450 mL of water, and add 50 mL of alcohol.

Sodium Alizarinsulfonate TS—Dissolve 100 mg of so- Use within 3 days.dium alizarinsulfonate in 100 mL of water, and filter. Sodium Thiosulfate TS—Use 0.1 N Sodium Thiosulfate

Sodium Aminoacetate TS (Sodium Glycinate TS)—Dis- (see in the section Volumetric Solutions).solve 3.75 g of aminoacetic acid in about 500 mL of water, Standard Lead Solution—See under Heavy Metals ⟨231⟩.add 2.1 g of sodium hydroxide, and dilute with water to Stannous Chloride, Acid, TS—Dissolve 8 g of stannous1000 mL. Mix 9 mL of the resulting solution with 1 mL of chloride in 500 mL of hydrochloric acid. Store in glass con-dilute glacial acetic acid (1 in 300). This test solution has a tainers, and use within 3 months.pH between 10.4 and 10.5. Stannous Chloride, Acid, Stronger, TS—Dissolve 40 g

Sodium Bisulfite TS—Dissolve 10 g of sodium bisulfite in of stannous chloride in 100 mL of hydrochloric acid. Store inwater to make 30 mL. Prepare this solution fresh. glass containers, and use within 3 months.

Sodium Bitartrate TS—Dissolve 1 g of sodium bitartrate Starch TS—Mix 1 g of soluble starch with 10 mg of redin water to make 10 mL. Prepare this solution fresh. mercuric iodide and sufficient cold water to make a thin

Sodium Carbonate TS—Dissolve 10.6 g of anhydrous so- paste. Add 200 mL of boiling water, and boil for 1 minutedium carbonate in water to make 100 mL. with continuous stirring. Cool, and use only the clear solu-

Sodium Chloride TS, Alkaline—Dissolve 2 g of sodium tion. [NOTE—Commercially available, stabilized starch indica-hydroxide in 100 mL of water, saturate the solution with tor solutions may be used, including mercury-free solutionssodium chloride, and filter. preserved with other compounds such as salicylic acid.]

Sodium Citrate TS—Dissolve 73.5 g of sodium citrate di- Starch, Iodide-Free, TS—Mix 1 g of soluble starch withhydrate in water to make 250 mL. sufficient cold water to make a thin paste. While stirring,

Sodium Citrate TS, Alkaline—Dissolve 50 g of sodium add 100 mL of boiling water, and allow to cool. Prepare thiscitrate dihydrate and 2.5 g of sodium hydroxide in water to solution immediately before use. Iodide-free starch TS showsmake 250 mL. a blue color when 20 mL of potassium iodide solution (1 in

Sodium Cobaltinitrite TS—Dissolve 10 g of sodium 400) and 0.05 mL of an iodine–potassium iodide solutioncobaltinitrite in water to make 50 mL, and filter if necessary. (prepared by dissolving 127 mg of iodine and 800 mg of

Sodium Fluoride TS—Dry about 500 mg of sodium fluo- potassium iodide in water and diluting with water toride at 200° for 4 hours. Accurately weigh 222 mg of the 100 mL) are added to 1 mL of the iodide-free starch TS.dried material, and dissolve in water to make 100.0 mL. Pi- Starch Iodide Paste TS—Heat 100 mL of water in apet 10 mL of this solution into a 1-L volumetric flask, and 250-mL beaker to boiling, add a solution of 0.75 g of potas-dilute with water to volume. Each mL of this solution corre- sium iodide in 5 mL of water, then add 2 g of zinc chloridesponds to 0.01 mg of fluorine (F). dissolved in 10 mL of water, and, while the solution is boil-

Sodium Hydrosulfite TS, Alkaline—Dissolve 25 g of po- ing, add, with stirring, a smooth suspension of 5 g of solu-tassium hydroxide in 35 mL of water, and 50 g of sodium ble starch in 30 mL of cold water. Continue to boil forhydrosulfite in 250 mL of water. When the test solution is 2 minutes, then cool. Store in well-closed containers in arequired, mix 40 mL of the hydroxide solution with the cold place.250 mL of the hydrosulfite solution. Prepare this solution Starch iodide paste TS must show a definite blue streakfresh. when a glass rod, dipped in a mixture of 1 mL of 0.1 M

Sodium Hydroxide TS—Dissolve 4.0 g of sodium hy- sodium nitrite, 500 mL of water, and 10 mL of hydrochloricdroxide in water to make 100 mL. acid, is streaked on a smear of the paste.

Sodium Hydroxide TS 2—Transfer 8.5 g of sodium hy- Starch–Potassium Iodide TS—Dissolve 500 mg of potas-droxide to a 100-mL volumetric flask, and dissolve in and sium iodide in 100 mL of freshly prepared starch TS. Preparedilute with water to volume. this solution fresh.

Sodium Hydroxide TS 3—Prepare a 420-mg/mL solution Stronger Cupric Acetate TS—See Cupric Acetate TS,of sodium hydroxide in water. Stronger.

Sodium Hypobromite TS—To a solution of 20 g of so- Sudan III TS—Dissolve 0.05 g of Sudan III in 25 mL ofdium hydroxide in 75 mL of water add 5 mL of bromine. alcohol, with warming if necessary. Cool, add 25 mL ofAfter solution has taken place, dilute with water to 100 mL. glycerin, and mix. Filter if undissolved material persists.Prepare this solution fresh. Sudan IV TS—Dissolve 0.5 g of Sudan IV in chloroform

to make 100 mL.


Sulfanilic Acid TS—Dissolve 800 mg of sulfanilic acid in Triphenyltetrazolium Chloride TS—Dissolve 500 mg of100 mL of acetic acid. Store in tight containers. triphenyltetrazolium chloride in dehydrated alcohol to make

Diazotized Sulfanilic Acid TS—Dissolve 0.9 g of sulfanilic 100 mL.acid in 9 mL of hydrochloric acid with warming, and dilute Xylenol Orange TS—Dissolve 100 mg of xylenol orangewith water to 100 mL. Cool 10 mL of this solution in iced in 100 mL of alcohol.water, and add 10 mL of a sodium nitrite solution (4.5 in Zinc Uranyl Acetate TS—Dissolve 50 g of uranyl acetate100) previously cooled in iced water. Allow to stand at 0° in a mixture of 15 mL of glacial acetic acid and water tofor at least 15 minutes (the solution may be kept for 3 days make 500 mL. Then dissolve 150 g of zinc acetate in a mix-at this temperature). Immediately before use, add 20 mL of ture of 15 mL of glacial acetic acid and water to makesodium carbonate solution (1 in 10). 500 mL. Mix the two solutions, allow to stand overnight,

Sulfanilic-1-Naphthylamine TS—Dissolve 500 mg of sul- and pass through a dry filter, if necessary.fanilic acid in 150 mL of acetic acid. Dissolve 100 mg of1-naphthylamine hydrochloride in 150 mL of acetic acid, VOLUMETRIC SOLUTIONSand mix the two solutions. The pink color that may developon standing can be removed by treatment with zinc. Normal Solutions—Normal solutions are solutions thatSulfanilic-α-Naphthylamine TS—See Sulfanilic-1-Naph- contain 1 gram equivalent weight of the active substance inthylamine TS. each 1000 mL of solution; that is, an amount equivalent toSulfomolybdic Acid TS—Dissolve, with the aid of heat, 1.0079 g of hydrogen or 7.9997 g of oxygen. Normal solu-2.5 g of ammonium molybdate in 20 mL of water, add tions and solutions bearing a specific relationship to normal50 mL of 12 N sulfuric acid, and dilute with water to solutions, and used in volumetric determinations, are desig-100 mL. Store this solution in a polyethylene container. nated as follows: normal, 1 N; double-normal, 2 N; half-nor-Sulfuric Acid TS—Add a quantity of sulfuric acid of mal, 0.5 N; tenth-normal, 0.1 N; fiftieth-normal, 0.02 N;known concentration to sufficient water to adjust the final hundredth-normal, 0.01 N; thousandth-normal, 0.001 N.concentration to between 94.5% and 95.5% (w/w) of Molar Solutions—Molar solutions are solutions that con-H2SO4. tain, in 1000 mL, 1 gram-molecule of the reagent. Thus,[NOTE—Since the acid concentration may change upon each liter of a molar solution of sulfuric acid containsstanding or upon intermittent use, the concentration should 98.07 g of H2SO4 and each liter of a molar solution of potas-be checked frequently and solutions assaying more than sium ferricyanide contains 329.25 g of K3Fe(CN)6. Solutions95.5% or less than 94.5% discarded.] containing, in 1000 mL, one-tenth of a gram-molecule ofSulfuric Acid–Formaldehyde TS—Add 1 drop of formal- the reagent are designated “tenth-molar,” 0.1 M; and otherdehyde TS to each mL of sulfuric acid, and mix. Prepare this molarities are similarly indicated.solution fresh. Empirical Solutions—It is frequently difficult to prepareTannic Acid TS—Dissolve 1 g of tannic acid in 1 mL of standard solutions of a desired theoretical normality, andalcohol, and dilute with water to 10 mL. Prepare this solu- this is not essential. A solution of approximately the desiredtion fresh. normality is prepared and standardized by titration against aTartaric Acid TS—Dissolve 3 g of tartaric acid in water to primary standard solution. The normality factor so obtainedmake 10 mL. Prepare this solution fresh. is used in all calculations where such empirical solutions areTetrabromophenolphthalein Ethyl Ester TS—Dissolve employed. If desired, an empirically prepared solution may100 mg of tetrabromophenolphthalein ethyl ester in 90 mL be adjusted downward to a given normality provided it isof glacial acetic acid, and dilute with glacial acetic acid to strong enough to permit dilution.100 mL. Prepare this solution fresh. All volumetric solutions, whether made by direct solutionTetramethylammonium Hydroxide TS—Use an aqueous or by dilution of a stronger solution, must be thoroughlysolution containing, in each 100 mL, the equivalent of 10 g mixed by shaking before standardization. As the strength ofof anhydrous tetramethylammonium hydroxide. a standard solution may change upon standing, the factorThioacetamide TS—Dissolve 4 g of thioacetamide in should be redetermined frequently.100 mL of water. When solutions of a reagent are used in several normali-Thioacetamide–Glycerin Base TS—Mix 0.2 mL of thio- ties, the details of the preparation and standardization areacetamide TS and 1 mL of glycerin base TS, and heat in a usually given for the normality most frequently required.boiling water bath for 20 seconds. Use the mixture immedi- Stronger or weaker solutions are prepared and standardizedately. in the same general manner as described, using proportion-Thorium Nitrate TS—Dissolve 1 g of thorium nitrate in ate amounts of the reagent. It is possible in many instanceswater to make 100 mL. Filter, if necessary. to prepare lower normalities accurately by making an exactThymol Blue TS—Dissolve 100 mg of thymol blue in dilution of a stronger solution. Volumetric solutions prepared100 mL of alcohol, and filter if necessary. by dilution should be restandardized either as directed forThymolphthalein TS—Dissolve 100 mg of thymolphtha- the stronger solution or by comparison with another volu-lein in 100 mL of alcohol, and filter if necessary. metric solution having a known ratio to the strongerTitanium Trichloride TS—Dissolve 15 g of titanium solution.trichloride in 100 mL of 10% hydrochloric acid solution. Dilute solutions that are not stable, as, for instance, potas-Titanium Trichloride–Sulfuric Acid TS—Mix carefully sium permanganate 0.01 N and more dilute sodium thiosul-20 mL of titanium trichloride TS in 13 mL of sulfuric acid. fate, are preferably prepared by exactly diluting the higherAdd sufficient 30% hydrogen peroxide to produce a yellow normality with thoroughly boiled and cooled water on thecolor. Heat until white fumes are evolved, allow to cool, and same day they are required for use.dilute with water. Repeat the evaporation and addition of Blank Determinations—Where it is directed that “anywater until a colorless solution is obtained. Dilute with water necessary correction” be made by a blank determination,to 100 mL. the determination is to be conducted with the use of thep-Toluenesulfonic Acid TS—Dissolve 2 g of p-tolu- same quantities of the same reagents treated in the sameenesulfonic acid in 10 mL of a mixture of 7 parts of acetone manner as the solution or mixture containing the portion ofand 3 parts of water. the substance under assay or test, but with the substanceTriketohydrindene Hydrate TS (Ninhydrin TS)—Dissolve itself omitted. Appropriate blank corrections are to be made200 mg of triketohydrindene hydrate in water to make for all Pharmacopeial titrimetric assays (see Titrimetry ⟨541⟩).10 mL. Prepare this solution fresh. All Pharmacopeial assays that are volumetric in nature in-Trinitrophenol TS (Picric Acid TS)—Dissolve the equiva- dicate the weight of the substance being assayed to whichlent of 1 g of anhydrous trinitrophenol in 100 mL of hot each mL of the primary volumetric solution is equivalent. Inwater. Cool the solution, and filter if necessary. general, these equivalents may be derived by simple calcula-

USP 36 Solutions / Volumetric Solutions 1219

tion from the data given under Molecular Formulas and Bromine, Tenth-Normal (0.1 N)Weights, in the Reference Tables. Br, 79.90

7.990 g in 1000 mLDissolve 3 g of potassium bromate and 15 g of potassium

Preparation and Methods of Standardization bromide in water to make 1000 mL, and standardize theof Volumetric Solutions solution as follows.

Accurately measure about 25 mL of the solution into aThe following directions give only one method for stan- 500-mL iodine flask, and dilute with 120 mL of water. Add

dardization, but other methods of standardization, capable 5 mL of hydrochloric acid, insert the stopper in the flask,of yielding at least the same degree of accuracy, may be and shake it gently. Then add 5 mL of potassium iodide TS,used. The values obtained in the standardization of volumet- again insert the stopper, shake the mixture, allow it to standric solutions are valid for all Pharmacopeial uses of these for 5 minutes, and titrate the liberated iodine with 0.1 Nsolutions, regardless of the instrumental or chemical indica- sodium thiosulfate VS, adding 3 mL of starch TS as thetors employed in the individual monographs. Where the ap- endpoint is approached.parent normality or molarity of a titrant depends upon the Preserve in dark amber-colored, glass-stoppered bottles.special conditions of its use, the individual monograph setsforth the directions for standardizing the reagent in thespecified context. For those salts that usually are available ascertified primary standards, or that are available as highlypurified salts of primary standard quality, it is permissible toprepare solutions by accurately weighing a suitable quantityof the salt and dissolving it to produce a specific volume of

Ceric Ammonium Nitrate, Twentieth-Normal (0.05 N)solution of known concentration. Acetic, hydrochloric, andCe(NO3)4 · 2NH4NO3, 548.22sulfuric acids may be standardized against a sodium hydrox-

2.741 g in 100 mLide solution that recently has been standardized against aDissolve 2.75 g of ceric ammonium nitrate in 1 N nitriccertified primary standard.

acid to obtain 100 mL of solution, and filter. Standardize theAll volumetric solutions, if practicable, are to be prepared,solution as follows.standardized, and used at the standard temperature of 25°.

Accurately measure 10 mL of freshly standardized 0.1 NIf a titration is carried out with the volumetric solution at aferrous ammonium sulfate VS into a flask, and dilute withmarkedly different temperature, standardize the volumetricwater to about 100 mL. Add 1 drop of nitrophenanthrolinesolution used as the titrant at that different temperature, orTS, and titrate with the ceric ammonium nitrate solution tomake a suitable temperature correction.a colorless endpoint.

Acetic Acid, Double-Normal (2 N)C2H4O2, 60.05

120.10 g in 1000 mLAdd 116 mL of glacial acetic acid to sufficient water to

make 1000 mL after cooling to room temperature.

Ceric Sulfate, Tenth-Normal (0.1 N)Ammonium Thiocyanate, Tenth-Normal (0.1 N)Ce(SO4)2, 332.24NH4SCN, 76.12

33.22 g in 1000 mL7.612 g in 1000 mLUse commercially available volumetric standard solution.Dissolve about 8 g of ammonium thiocyanate in 1000 mL

Standardize the solution as follows.of water, and standardize the solution as follows.Accurately weigh about 0.2 g of sodium oxalate, primaryAccurately measure about 30 mL of 0.1 N silver nitrate VS

standard, dried according to the instructions on its label,into a glass-stoppered flask. Dilute with 50 mL of water,and dissolve in 75 mL of water. Add, with stirring, 2 mL ofthen add 2 mL of nitric acid and 2 mL of ferric ammoniumsulfuric acid that has previously been mixed with 5 mL ofsulfate TS, and titrate with the ammonium thiocyanate solu-water, mix well, add 10 mL of hydrochloric acid, and heattion to the first appearance of a red-brown color.to between 70° and 75°. Titrate with 0.1 N ceric sulfate to apermanent slight yellow color. Each 6.700 mg of sodium ox-alate is equivalent to 1 mL of 0.1 N ceric sulfate.

If desirable, 0.1 N ammonium thiocyanate may be re-placed by 0.1 N potassium thiocyanate where the former isdirected in various tests and assays.

Cupric Nitrate, Tenth-Normal (0.1 N)Bismuth Nitrate, 0.01 MCu(NO3)2 · 2.5H2O, 232.59Bi(NO3)3 · 5H2O, 485.07

23.26 g in 1000 mL1000 mL of this solution contains 4.851 g of bismuth nitrateCu(NO3)2 · 3H2O, 241.60pentahydrate

24.16 g in 1000 mLDissolve 4.86 g of bismuth nitrate pentahydrate in 60 mLDissolve 23.3 g of cupric nitrate 2.5 hydrate, or 24.2 g ofof dilute nitric acid, add 0.01 N nitric acid to make

the trihydrate, in water to make 1000 mL. Standardize the1000 mL, and standardize the solution as follows.solution as follows.Accurately measure 25 mL of the prepared bismuth nitrate

Transfer 20.0 mL of the solution to a 250-mL beaker. Addsolution, add 50 mL of water and 1 drop of xylenol orange2 mL of 5 M sodium nitrate, 20 mL of ammonium acetateTS, and titrate the solution with 0.01 M edetate disodiumTS, and sufficient water to make 100 mL. Titrate withVS until the red color changes to yellow. Calculate the mo-0.05 M edetate disodium VS. Determine the endpoint po-larity factor.tentiometrically using a cupric ion-double junction reference

1220 Volumetric Solutions / Solutions USP 36

electrode system. Perform a blank determination, and make Store in tight containers, protected from light.any necessary correction.

Standard Dichlorophenol–Indophenol Solution Ferrous Ammonium Sulfate, Tenth-Normal (0.1 N)To 50 mg of 2,6-dichlorophenol–indophenol sodium that Fe(NH4)2(SO4)2 · 6H2O, 392.14

has been stored in a desiccator over soda lime add 50 mL of 39.21 g in 1000 mLwater containing 42 mg of sodium bicarbonate, shake vigor- Dissolve 40 g of ferrous ammonium sulfate in a previouslyously, and when the dye is dissolved, add water to make cooled mixture of 40 mL of sulfuric acid and 200 mL of200 mL. Filter into an amber, glass-stoppered bottle. Use water, dilute with water to 1000 mL, and mix. On the daywithin 3 days and standardize immediately before use. Stan- of use, standardize the solution as follows.dardize the solution as follows. Accurately measure 25 to 30 mL of the solution into a

Accurately weigh 50 mg of USP Ascorbic Acid RS, and flask, add 2 drops of orthophenanthroline TS, and titratetransfer to a glass-stoppered, 50-mL volumetric flask with with 0.1 N ceric sulfate VS until the red color is changed tothe aid of a sufficient volume of metaphosphoric–acetic pale blue.acids TS to make 50 mL. Immediately transfer 2 mL of theascorbic acid solution to a 50-mL conical flask containing5 mL of the metaphosphoric–acetic acids TS, and titrate rap-idly with the dichlorophenol–indophenol solution until a dis-tinct rose-pink color persists for at least 5 seconds. Perform ablank titration by titrating 7 mL of the metaphosphoric–acetic acids TS plus a volume of water equal to the volume Hydrochloric Acid, Alcoholic, Tenth-Molar (0.1 M)of the dichlorophenol solution used in titrating the ascorbic HCl, 36.46acid solution. Express the concentration of the standard so- Dilute 9.0 mL of hydrochloric acid to 1000 mL with al-lution in terms of its equivalent in mg of ascorbic acid. dehyde–free alcohol.

Edetate Disodium, Twentieth-Molar (0.05 M) Hydrochloric Acid, Half-Normal (0.5 N)C10H14N2Na2O8 · 2H2O, 372.24 HCl, 36.46

18.61 g in 1000 mL 18.23 g in 1000 mLDissolve 18.6 g of edetate disodium in water to make To a 1000-mL volumetric flask containing 40 mL of water

1000 mL, and standardize the solution as follows. slowly add 43 mL of hydrochloric acid. Cool, and add waterAccurately weigh about 200 mg of chelometric standard to volume. Standardize the solution as follows.

calcium carbonate, previously dried at 110° for 2 hours and Accurately weigh about 2.5 g of tromethamine, dried ac-cooled in a desiccator, or dried according to the label in- cording to the label instructions or, if this information is notstructions, transfer to a 400-mL beaker, add 10 mL of water, available, dried at 105° for 3 h. Dissolve in 50 mL of water,and swirl to form a slurry. Cover the beaker with a watch and add 2 drops of bromocresol green TS. Titrate with 0.5glass, and introduce 2 mL of diluted hydrochloric acid from N hydrochloric acid to a pale yellow endpoint. Eacha pipet inserted between the lip of the beaker and the edge 60.57 mg of tromethamine is equivalent to 1 mL of 0.5 Nof the watch glass. Swirl the contents of the beaker to dis- hydrochloric acid.solve the calcium carbonate. Wash down the sides of thebeaker, the outer surface of the pipet, and the watch glasswith water, and dilute with water to about 100 mL. Whilestirring the solution, preferably with a magnetic stirrer, addabout 30 mL of the edetate disodium solution from a 50-mLburet. Add 15 mL of sodium hydroxide TS and 300 mg ofhydroxy naphthol blue, and continue the titration with the Hydrochloric Acid, Half-Normal (0.5 N) in Methanoledetate disodium solution to a blue endpoint. HCl, 36.46

18.23 g in 1000 mLTo a 1000-mL volumetric flask containing 40 mL of water

slowly add 43 mL of hydrochloric acid. Cool, and add meth-anol to volume. Standardize the solution as follows.

Accurately weigh about 2.5 g of tromethamine, dried ac-cording to the label instructions or, if this information is not

Ferric Ammonium Sulfate, Tenth-Normal (0.1 N) available, dried at 105° for 3 h. Proceed as directed underFeNH4(SO4)2 · 12H2O, 482.19 Hydrochloric Acid, Normal (1 N), beginning with “Dissolve in

48.22 g in 1000 mL 50 mL of water.”Dissolve 50 g of ferric ammonium sulfate in a mixture of

300 mL of water and 6 mL of sulfuric acid, dilute with waterto 1000 mL, and mix. Standardize the solution as follows.

Accurately measure about 40 mL of the solution into aglass-stoppered flask, add 5 mL of hydrochloric acid, mix,and add a solution of 3 g of potassium iodide in 10 mL ofwater. Insert the stopper, allow to stand for 10 minutes, Hydrochloric Acid, Normal (1 N)then titrate the liberated iodine with 0.1 N sodium thiosul- HCl, 36.46fate VS, adding 3 mL of starch TS as the endpoint is ap- 36.46 g in 1000 mLproached. Correct for a blank run on the same quantities of Dilute 85 mL of hydrochloric acid with water to 1000 mL.the same reagents. Standardize the solution as follows.

Accurately weigh about 5.0 g of tromethamine, dried ac-cording to the label instructions or, if this information is notavailable, dried at 105° for 3 h. Dissolve in 50 mL of water,and add 2 drops of bromocresol green TS. Titrate with 1 N


hydrochloric acid to a pale yellow endpoint. Each 0.1 M Lead Nitrate—Dissolve 33 g of lead nitrate in121.14 mg of tromethamine is equivalent to 1 mL of 1 N 1000 mL of water. Standardize the solution as follows. Tohydrochloric acid. 20.0 mL of the lead nitrate solution add 300 mL of water.

Add about 50 mg of Xylenol Orange Triturate, and add me-thenamine until the solution becomes violet-pink. Titratewith 0.1 M edetate disodium VS to the yellow endpoint.Calculate the molarity.

Dilute 50.0 mL of 0.1 M Lead Nitrate to 500.0 mL withwater.

Iodine, Tenth-Normal (0.1 N)I, 126.90 Lead Perchlorate, Tenth-Molar (0.1 M)

12.69 g in 1000 mL Pb(ClO4)2 · 3H2O, 460.15Dissolve about 14 g of iodine in a solution of 36 g of po- 46.01 g in 1000 mL

tassium iodide in 100 mL of water, add 3 drops of hydro- Dissolve 46 g of lead perchlorate in water, and dilute withchloric acid, dilute with water to 1000 mL, and standardize water to 1000.0 mL. Accurately weigh about 150 mg of so-the solution as follows. dium sulfate, previously dried at 105° for 4 hours, and dis-

Transfer 25.0 mL of the iodine solution to a 250-mL flask, solve in 50 mL of water. Add 50 mL of a mixture of waterdilute with water to 100 mL, add 1 mL of 1 N hydrochloric and formaldehyde (1:1), and stir for about 1 minute. Deter-acid, swirl gently to mix, and titrate with 0.1 N sodium mine the endpoint potentiometrically using a lead ion selec-thiosulfate VS until the solution has a pale yellow color. Add tive electrode. Perform a blank determination, and make2 mL of starch TS and continue titrating until the solution is any necessary corrections. Each 14.204 mg of sodium sulfatecolorless. is equivalent to 1 mL of 0.1 M lead perchlorate.

Preserve in amber-colored, glass-stoppered bottles.

Lead Perchlorate, Hundredth-Molar (0.01 M)Iodine, Twentieth-Normal (0.05 N) Pb(ClO4)2, 406.10

I, 126.90 Accurately pipet 100 mL of commercially available 0.1 M6.33 g in 1000 mL lead perchlorate solution into a 1000-mL volumetric flask,

Dissolve about 6.5 g of iodine in a solution of 18 g of add a sufficient quantity of water to make 1000 mL, andpotassium iodide in 100 mL of water, add 3 drops of hydro- standardize the solution as follows.chloric acid, dilute with water to 1000 mL, and standardize Accurately pipet 50 mL of 0.01 M lead perchlorate solu-the solution as follows. tion, as prepared above, into a 250-mL conical flask. Add

Transfer 50.0 mL of the iodine solution to a 250-mL flask, 3 mL of aqueous hexamethylenetetramine solution (2.0 gdilute with water to 100 mL, add 1 mL of 1 N hydrochloric per 100 mL) and 4 drops of 0.5% xylenol orange indicatoracid, swirl gently to mix, and titrate with 0.1 N sodium prepared by adding 500 mg of xylenol orange to 10 mL ofthiosulfate VS until the solution has a pale yellow color. Add alcohol and diluting with water to 100 mL. (Omit the alco-2 mL of starch TS, and continue titrating until the solution is hol if the sodium salt of the indicator is used). Titrate withcolorless. 0.05 M edetate disodium VS to a yellow endpoint.

Iodine, Hundredth-Normal (0.01 N) Lithium Methoxide, Fiftieth-Normal (0.02 N) inI, 126.90 Methanol

1.269 g in 1000 mL CH3LiO, 37.97Dissolve about 1.4 g of iodine in a solution of 3.6 g of 759.6 mg in 1000 mL

potassium iodide in 100 mL of water, add 3 drops of hydro- Dissolve 0.12 g of freshly cut lithium metal in 150 mL ofchloric acid, dilute with water to 1000 mL, and standardize methanol, cooling the flask during addition of the metal.the solution as follows. When the reaction is complete, add 850 mL of methanol,

Transfer 100.0 mL of iodine solution to a 250-mL flask, and mix. Store the solution preferably in the reservoir of anadd 1 mL of 1 N hydrochloric acid, swirl gently to mix, and automatic delivery buret suitably protected from carbon di-titrate with 0.1 N sodium thiosulfate VS until the solution oxide and moisture. Standardize the solution by titrationhas a pale yellow color. Add 2 mL of starch TS, and con- against benzoic acid as described under Sodium Methoxide,tinue titrating until the solution is colorless. Tenth-Normal (0.1 N) (in Toluene), but use only 100 mg of

Preserve in amber-colored, glass-stoppered bottles. benzoic acid. Each 2.442 mg of benzoic acid is equivalent to1 mL of 0.02 N lithium methoxide.

[NOTE—Restandardize the solution frequently.]

Lead Nitrate, Hundredth-Molar (0.01 M)Pb (NO3)2, 331.21 Lithium Methoxide, Tenth-Normal (0.1 N) in3.312 g in 1000 mL Chlorobenzene

Xylenol Orange Triturate—Triturate 1 part of xylenol or- CH3OLi, 37.97ange with 99 parts of potassium nitrate. 3.798 g in 1000 mL


Dissolve 700 mg of freshly cut lithium metal in 150 mL of Dissolve about 35 g of mercuric nitrate in a mixture ofmethanol, cooling the flask during addition of the metal. 5 mL of nitric acid and 500 mL of water, and dilute withWhen the reaction is complete, add 850 mL of chloroben- water to 1000 mL. Standardize the solution as follows.zene. If cloudiness or precipitation occurs, add sufficient Transfer an accurately measured volume of about 20 mLmethanol to clarify the solution. Store preferably in the res- of the solution to a conical flask, and add 2 mL of nitric acidervoir of an automatic delivery buret suitably protected from and 2 mL of ferric ammonium sulfate TS. Cool to belowcarbon dioxide and moisture. Standardize the solution by 20°, and titrate with 0.1 N ammonium thiocyanate VS totitration against benzoic acid as described under Sodium the first appearance of a permanent brownish color.Methoxide, Tenth-Normal (0.1 N) (in Toluene).

[NOTE—Restandardize the solution frequently.]

Oxalic Acid, Tenth-Normal (0.1 N)H2C2O4 · 2H2O, 126.07Lithium Methoxide, Tenth-Normal (0.1 N) in Methanol 6.303 g in 1000 mLCH3OLi, 37.97 Dissolve 6.45 g of oxalic acid in water to make 1000 mL.3.798 g in 1000 mL Standardize by titration against freshly standardized 0.1 NDissolve 700 mg of freshly cut lithium metal in 150 mL of potassium permanganate VS as directed under Potassiummethanol, cooling the flask during addition of the metal. Permanganate, Tenth-Normal (0.1 N).When the reaction is complete, add 850 mL of methanol. If Preserve in glass-stoppered bottles, protected from light.cloudiness or precipitation occurs, add sufficient methanol

to clarify the solution. Store preferably in the reservoir of anautomatic delivery buret suitably protected from carbon di-oxide and moisture. Standardize the solution by titrationagainst benzoic acid as described under Sodium Methoxide,Tenth-Normal (0.1 N) (in Toluene).

[NOTE—Restandardize the solution frequently.]Perchloric Acid, Tenth-Normal (0.1 N) in Dioxane

Mix 8.5 mL of perchloric acid with sufficient dioxane tomake 1000 mL. Standardize the solution as follows.

Accurately weigh about 700 mg of potassium biphthalate,previously crushed lightly and dried at 120° for 2 hours, anddissolve in 50 mL of glacial acetic acid in a 250-mL flask.Add 2 drops of crystal violet TS, and titrate with the per-Lithium Methoxide, Tenth-Normal (0.1 N) in Toluenechloric acid solution until the violet color changes to bluishCH3OLi, 37.97green. Carry out a blank determination. Each 20.423 mg of3.798 g in 1000 mLpotassium biphthalate is equivalent to 1 mL of 0.1 N per-Dissolve 700 mg of freshly cut lithium metal in 150 mL ofchloric acid.methanol, cooling the flask during addition of the metal.

When reaction is complete, add 850 mL of toluene. If cloud-iness or precipitation occurs, add sufficient methanol to clar-ify the solution. Store preferably in the reservoir of an auto-matic delivery buret suitably protected from carbon dioxideand moisture. Standardize the solution by titration againstbenzoic acid as described under Sodium Methoxide, Tenth-

Perchloric Acid, Tenth-Normal (0.1 N) in Glacial AceticNormal (0.1 N) (in Toluene).Acid[NOTE—Restandardize the solution frequently.]

HClO4, 100.4610.05 g in 1000 mL

[NOTE—Where called for in the tests and assays, this volu-metric solution is specified as “0.1 N perchloric acid.” Thus,where 0.1 N or other strength of this volumetric solution isspecified, the solution in glacial acetic acid is to be used,unless the words “in dioxane” are stated. [See also PerchloricMagnesium Chloride, 0.01 MAcid, Tenth-Normal (0.1 N) in Dioxane.]]MgCl2 · 6H2O, 203.30

Mix 8.5 mL of perchloric acid with 500 mL of glacial ace-2.0330 g in 1000 mLtic acid and 21 mL of acetic anhydride, cool, and add glacialDissolve about 2.04 g of magnesium chloride in 1000 mLacetic acid to make 1000 mL. Alternatively, the solution mayof freshly boiled and cooled water, and standardize the solu-be prepared as follows. Mix 11 mL of 60 percent perchloriction as follows.acid with 500 mL of glacial acetic acid and 30 mL of aceticAccurately measure 25 mL of the prepared magnesiumanhydride, cool, and add glacial acetic acid to makechloride solution. Add 50 mL of water, 3 mL of am-1000 mL.monia–ammonium chloride buffer TS and 0.04 g of eri-

Allow the prepared solution to stand for 1 day for theochrome black T–sodium chloride reagent. Titrate withexcess acetic anhydride to be combined, and determine the0.05 M edetate disodium VS until the red-purple color ofwater content by Method I (see Water Determination ⟨921⟩),the solution changes to blue-purple.except to use a test specimen of about 5 g of the 0.1 Nperchloric acid that is expected to contain approximately1 mg of water and the Reagent (see Reagent under MethodIa in Water Determination ⟨921⟩) diluted such that 1 mL isequivalent to about 1 to 2 mg of water. If the water contentexceeds 0.5%, add more acetic anhydride. If the solution

Mercuric Nitrate, Tenth-Molar (0.1 M) contains no titratable water, add sufficient water to obtain aHg(NO3)2, 324.60 content of between 0.02% and 0.5% of water. Allow the

32.46 g in 1000 mL solution to stand for 1 day, and again titrate the water con-


tent. The solution so obtained contains between 0.02% and Potassium Ferricyanide, Twentieth-Molar (0.05 M)0.5% of water, indicating freedom from acetic anhydride. K3Fe(CN)6, 329.24

Standardize the solution as follows. 16.46 g in 1000 mLAccurately weigh about 700 mg of potassium biphthalate, Dissolve about 17 g of potassium ferricyanide in water to

previously crushed lightly and dried at 120° for 2 hours, and make 1000 mL. Standardize the solution as follows.dissolve it in 50 mL of glacial acetic acid in a 250-mL flask. Transfer 50.0 mL of this solution to a glass-stoppered,Add 2 drops of crystal violet TS, and titrate with the per- 500-mL flask, dilute with 50 mL of water, add 10 mL of po-chloric acid solution until the violet color changes to blue- tassium iodide TS and 10 mL of dilute hydrochloric acid,green. Deduct the volume of the perchloric acid consumed and allow to stand for 1 minute. Then add 15 mL of zincby 50 mL of the glacial acetic acid. Each 20.423 mg of po- sulfate solution (1 in 10), and titrate the liberated iodinetassium biphthalate is equivalent to 1 mL of 0.1 N perchloric with 0.1 N sodium thiosulfate VS, adding 3 mL of starch TSacid. as the endpoint is approached.

Protect from light, and restandardize before use.

Potassium Arsenite, Tenth-Normal (0.1 N)KAsO2, 146.02 Potassium Hydroxide, Alcoholic, Half-Normal (0.5 N)7.301 g in 1000 mL 28.06 g in 1000 mLDissolve 4.9455 g of arsenic trioxide primary standard, Dissolve about 34 g of potassium hydroxide in 20 mL ofpreviously dried at 105° for 1 hour, in 75 mL of 1 N potas- water, and add aldehyde-free alcohol to make 1000 mL. Al-sium hydroxide. Add 40 g of potassium bicarbonate, dis- low the solution to stand in a tightly stoppered bottle forsolved in about 200 mL of water, and dilute with water to 24 hours. Then quickly decant the clear supernatant into a1000.0 mL. suitable, tight container, and standardize the solution as

follows.Potassium Bromate, Tenth-Normal (0.1 N) Accurately measure about 25 mL of 0.5 N hydrochloric

KBrO3, 167.00 acid VS. Dilute with 50 mL of water, add 2 drops of phenol-2.784 g in 1000 mL phthalein TS, and titrate with the alcoholic potassium hy-

Dissolve 2.784 g of potassium bromate in water to make droxide solution until a permanent, pale pink color is pro-1000 mL, and standardize the solution as follows. duced.

Transfer an accurately measured volume of about 40 mL [NOTE—Store in tightly stoppered bottles, protected fromof the solution to a glass-stoppered flask, add 3 g of potas- light.]sium iodide, and follow with 3 mL of hydrochloric acid. Al-low to stand for 5 minutes, then titrate the liberated iodinewith 0.1 N sodium thiosulfate VS, adding 3 mL of starch TSas the endpoint is approached. Correct for a blank run onthe same quantities of the same reagents, and calculate thenormality.

Potassium Hydroxide, Alcoholic, Tenth-Molar (0.1 M) KOH, 56.11

Dilute 20 mL of 0.5 M alcoholic potassium hydroxide to100.0 mL with aldehyde-free alcohol.

Potassium Hydroxide, Methanolic, Tenth-NormalPotassium Bromide–Bromate, Tenth-Normal (0.1 N) (0.1 N)Dissolve 2.78 g of potassium bromate (KBrO3) and 12.0 g 5.612 g in 1000 mLof potassium bromide (KBr) in water, and dilute with water Dissolve about 6.8 g of potassium hydroxide in 4 mL ofto 1000 mL. Standardize by the procedure set forth for Po- water, and add methanol to make 1000 mL. Allow the solu-tassium Bromate, Tenth-Normal (0.1 N). tion to stand in a tightly stoppered bottle for 24 hours.Then quickly decant the clear supernatant into a suitable,tight container, and standardize the solution as follows.

Accurately measure about 25 mL of 0.1 N hydrochloricacid VS. Dilute with 50 mL of water, add 2 drops of phenol-phthalein TS, and titrate with the methanolic potassium hy-droxide solution until a permanent, pale pink color is pro-

Potassium Dichromate, Tenth-Normal (0.1 N) duced.K2Cr2O7, 294.18 [NOTE—Store in tightly stoppered bottles, protected from

4.903 g in 1000 mL light.]Dissolve about 5 g of potassium dichromate in 1000 mL

of water. Standardize the solution as follows.Transfer 25.0 mL of this solution to a glass-stoppered,

500-mL flask, add 2 g of potassium iodide (free from io-date), dilute with 200 mL of water, add 5 mL of hydrochlo-ric acid, allow to stand for 10 minutes in a dark place, andtitrate the liberated iodine with 0.1 N sodium thiosulfate VS, Potassium Hydroxide, Normal (1 N)adding 3 mL of starch TS as the endpoint is approached. KOH, 56.11Carry out a blank determination. 56.11 g in 1000 mL

Dissolve 68 g of potassium hydroxide in about 950 mL ofwater. Add a freshly prepared saturated solution of bariumhydroxide until no more precipitate forms. Shake the mix-ture thoroughly, and allow it to stand overnight in a stop-pered bottle. Decant the clear liquid, or filter the solution in


a tight, polyolefin bottle, and standardize by the procedure Silver Nitrate, Tenth-Normal (0.1 N)set forth for Sodium Hydroxide, Normal (1 N). AgNO3, 169.87

16.99 g in 1000 mLDissolve about 17.5 g of silver nitrate in 1000 mL of

water, and standardize the solution as follows.Transfer about 100 mg, accurately weighed, of reagent-

grade sodium chloride, previously dried at 110° for 2 hours,to a 150-mL beaker, dissolve in 5 mL of water, and add5 mL of acetic acid, 50 mL of methanol, and about 0.5 mLPotassium Iodate, Twentieth-Molar (0.05 M)of eosin Y TS. Stir, preferably with a magnetic stirrer, andKIO3, 214.00titrate with the silver nitrate solution.10.70 g in 1000 mL

Dissolve 10.700 g of potassium iodate, previously dried at110° to constant weight, in water to make 1000.0 mL. Stan-dardize the solution as follows: to 15.0 mL of solution in a250-mL iodine flask, add 3 g of potassium iodide and 3 mLof hydrochloric acid previously diluted with 10 mL of water.Stopper immediately, and allow to stand in the dark for5 minutes. Then add 50 mL of cold water, and titrate the Sodium Arsenite, Twentieth-Molar (0.05 M)liberated iodine with freshly standardized 0.1 N sodium thi- NaAsO2 129.91osulfate. Add 3 mL of starch indicator solution near the end 6.496 g in 1000 mLof the titration, and continue to the absence of the blue- Transfer 4.9455 g of arsenic trioxide, which has been pul-starch-iodine complex. verized and dried at 100° to constant weight, to a 1000-mL

volumetric flask, dissolve it in 40 mL of 1 N sodium hydrox-ide, and add 1 N sulfuric acid or 1 N hydrochloric acid untilthe solution is neutral or only slightly acid to litmus. Add30 g of sodium bicarbonate, dilute with water to volume,and mix.

Potassium Permanganate, Tenth-Normal (0.1 N) Sodium Hydroxide, Alcoholic, Tenth-Normal (0.1 N)KMnO4, 158.03 NaOH, 40.00

3.161 g in 1000 mL To 250 mL of alcohol add 2 mL of a 50% (w/v) solutionDissolve about 3.3 g of potassium permanganate in of sodium hydroxide.

1000 mL of water in a flask, and boil the solution for about Dissolve about 200 mg of benzoic acid, accurately15 minutes. Insert the stopper in the flask, allow it to stand weighed, in 10 mL of alcohol and 2 mL of water. Addfor at least 2 days, and filter through a fine-porosity, 2 drops of phenolphthalein TS, and titrate with the alcoholicsintered-glass crucible. If necessary, the bottom of the sodium hydroxide solution until a permanent pale pink colorsintered-glass crucible may be lined with a pledget of glass is produced.wool. Standardize the solution as follows.

Accurately weigh about 200 mg of sodium oxalate, driedaccording to the instructions on its label, and dissolve it in250 mL of water. Add 7 mL of sulfuric acid, heat to about70°, and then slowly add the permanganate solution from aburet, with constant stirring, until a pale pink color, whichpersists for 15 seconds, is produced. The temperature at the Sodium Hydroxide, Normal (1 N)conclusion of the titration should be not less than 60°. Cal- NaOH, 40.00culate the normality. Each 6.700 mg of sodium oxalate is 40.00 g in 1000 mLequivalent to 1 mL of 0.1 N potassium permanganate. Dissolve 162 g of sodium hydroxide in 150 mL of carbon

Since potassium permanganate is reduced on contact dioxide-free water, cool the solution to room temperature,with organic substances such as rubber, the solution must and filter through hardened filter paper. Transfer 54.5 mL ofbe handled in apparatus entirely of glass or other suitably the clear filtrate to a tight, polyolefin container, and diluteinert material. It should be frequently restandardized. Store with carbon dioxide-free water to 1000 mL.in glass-stoppered, amber-colored bottles. Accurately weigh about 5 g of potassium biphthalate, pre-

viously crushed lightly and dried at 120° for 2 hours, anddissolve in 75 mL of carbon dioxide-free water. Add 2 dropsof phenolphthalein TS, and titrate with the sodium hydrox-ide solution to the production of a permanent pink color.Each 204.22 mg of potassium biphthalate is equivalent to1 mL of 1 N sodium hydroxide.

Potassium Thiocyanate, Tenth-Normal (0.1 N)KSCN, 97.18

9.72 g in 1000 mLWeigh exactly 9.72 g of potassium thiocyanate, previously

[NOTES—(1) Solutions of alkali hydroxides absorb carbondried for 2 hours at 110°, transfer to a 1-L volumetric flask,dioxide when exposed to air. They should be preserved indilute with water to volume, and mix well. Standardize asbottles having well-fitted, suitable stoppers, provided with afollows: transfer 40.0 mL of freshly standardized 0.1 N silvertube filled with a mixture of sodium hydroxide and limenitrate VS to a 250-mL Erlenmeyer flask; and add 100 mL of(soda-lime tubes) so that air entering the container mustwater, 1 mL of nitric acid, and 2 mL of ferric ammoniumpass through this tube, which will absorb the carbon diox-sulfate TS. Titrate with the potassium thiocyanate solution,ide. (2) Prepare solutions of lower concentration (e.g.,with agitation, to a permanent light pinkish-brown color of0.1 N, 0.01 N) by quantitatively diluting accurately meas-the supernatant.ured volumes of the 1 N solution with sufficient carbon di-oxide-free water to yield the desired concentration.]

Restandardize the solution frequently.


Sodium Methoxide, Half-Normal (0.5 N) in Methanol 1 mL of the endpoint, add the titrant in 0.1-mL portions,CH3ONa, 54.02 and allow 1 minute between additions. Each 17.22 mg of

27.01 g in 1000 mL sulfanilamide is equivalent to 1 mL of 0.1000 M sodiumWeigh 11.5 g of freshly cut sodium metal, and cut into nitrite.

small cubes. Place about 0.5 mL of anhydrous methanol in around-bottom, 250-mL flask equipped with a ground-glassjoint, add 1 cube of the sodium metal, and, when the reac-tion has ceased, add the remaining sodium metal to theflask. Connect a water-jacketed condenser to the flask, andslowly add 250 mL of anhydrous methanol, in small por-tions, through the top of the condenser. Regulate the addi- Sodium Tetraphenylboron, Fiftieth-Molar (0.02 M)tion of the methanol so that the vapors are condensed and NaB(C6H5)4, 342.22do not escape through the top of the condenser. After addi- 6.845 g in 1000 mLtion of the methanol is complete, connect a drying tube to Dissolve an amount of sodium tetraphenylboron, equiva-the top of the condenser, and allow the solution to cool. lent to 6.845 g of NaB(C6H5)4, in water to make 1000 mL,Transfer the solution to a 1-L volumetric flask, dilute with and standardize the solution as follows.anhydrous methanol to volume, and mix. Standardize the Pipet two 75-mL portions of the solution into separatesolution as follows. beakers, and to each add 1 mL of acetic acid and 25 mL of

Accurately measure about 20 mL of freshly standardized water. To each beaker add, slowly and with constant stir-1 N hydrochloric acid VS into a 250-mL conical flask, add ring, 25 mL of potassium biphthalate solution (1 in 20), and0.25 mL of phenolphthalein TS, and titrate with the sodium allow to stand for 2 hours. Filter one of the mixturesmethoxide solution to the first appearance of a permanent through a filtering crucible, and wash the precipitate withpink color. cold water. Transfer the precipitate to a container, add

50 mL of water, shake intermittently for 30 minutes, filter,and use the filtrate as the saturated potassium tetraphenyl-borate solution in the following standardization procedure.Filter the second mixture through a tared filtering crucible,and wash the precipitate with three 5-mL portions of satu-rated potassium tetraphenylborate solution. Dry the precipi-

Sodium Methoxide, Tenth-Normal (0.1 N) in Toluene tate at 105° for 1 hour. Each g of potassium tetraphenylbo-CH3ONa, 54.02 rate (KTPB) is equivalent to 955.1 mg of sodium

5.402 g in 1000 mL tetraphenylboron.Cool in ice-water 150 mL of methanol contained in a

1000-mL volumetric flask, and add, in small portions, about2.5 g of freshly cut sodium metal. When the metal has dis-solved, add toluene to make 1000 mL, and mix. Store pref-erably in the reservoir of an automatic delivery buret suita-bly protected from carbon dioxide and moisture. [NOTE—Prepare this solution just before use.]Standardize the solution as follows.

Accurately weigh about 400 mg of primary standard ben- Sodium Thiosulfate, Tenth-Normal (0.1 N)zoic acid, and dissolve in 80 mL of dimethylformamide in a Na2S2O3 · 5H2O, 248.19flask. Add 3 drops of a 1 in 100 solution of thymol blue in 24.82 g in 1000 mLdimethylformamide, and titrate with the sodium methoxide Dissolve about 26 g of sodium thiosulfate and 200 mg ofto a blue endpoint. Correct for the volume of the sodium sodium carbonate in 1000 mL of recently boiled and cooledmethoxide solution consumed by 80 mL of the dimethyl- water. Standardize the solution as follows.formamide. Each 12.21 mg of benzoic acid is equivalent to Accurately weigh about 210 mg of primary standard po-1 mL of 0.1 N sodium methoxide. tassium dichromate, previously pulverized and dried accord-

ing to the instructions on its label, if necessary, and dissolvein 100 mL of water in a glass-stoppered, 500-mL flask. Swirlto dissolve the solid, remove the stopper, and quickly add3 g of potassium iodide, 2 g of sodium bicarbonate, and5 mL of hydrochloric acid. Insert the stopper gently in the[NOTES—(1) To eliminate any turbidity that may form fol-flask, swirl to mix, and allow to stand in the dark for exactlylowing dilution with toluene, add methanol (25 to 30 mL10 minutes. Rinse the stopper and the inner walls of theusually suffices) until the solution is clear. (2) Restandardizeflask with water, and titrate the liberated iodine with thethe solution frequently.]sodium thiosulfate solution until the solution is yellowishgreen in color. Add 3 mL of starch TS, and continue theSodium Nitrite, Tenth-Molar (0.1 M) titration until the blue color is discharged. Perform a blankNaNO2, 69.00 determination.6.900 g in 1000 mL Restandardize the solution as frequently as supported byDissolve 7.5 g of sodium nitrite in water to make laboratory stability data. In the absence of such data,1000 mL, and standardize the solution as follows. restandardize the solution weekly.Accurately weigh about 500 mg of USP Sulfanilamide RS,

previously dried at 105° for 3 hours, and transfer to a suita-ble beaker. Add 20 mL of hydrochloric acid and 50 mL ofwater, stir until dissolved, and cool to 15°. Maintaining thetemperature at about 15°, titrate slowly with the sodiumnitrite solution, placing the buret tip below the surface ofthe solution to preclude air oxidation of the sodium nitrite,

Sulfuric Acid, Half-Normal (0.5 N) in Alcoholand stir the solution gently with a magnetic stirrer, butH2SO4, 98.08avoid pulling a vortex of air beneath the surface. Use the

24.52 g in 1000 mLindicator specified in the individual monograph, or, if aAdd slowly, with stirring, 13.9 mL of sulfuric acid to apotentiometric procedure is specified, determine the

sufficient quantity of dehydrated alcohol to make 1000 mL.endpoint electrometrically, using platinum–calomel or pla-tinum–platinum electrodes. When the titration is within


Cool, and standardize against tromethamine as described Tetramethylammonium Bromide, Tenth-Molar (0.1 M)under Hydrochloric Acid, Half-Normal (0.5 N) in Methanol. (CH3)4NBr, 154.05

15.41 g in 1000 mLDissolve 15.41 g of tetramethylammonium bromide in

water to make 1000 mL, and standardize the solution asfollows.

Transfer an accurately measured volume of about 40 mLof the solution to a beaker, add 10 mL of diluted nitric acidand 50.0 mL of 0.1 N silver nitrate VS, and mix. Add 2 mLSulfuric Acid, Normal (1 N)of ferric ammonium sulfate TS, and titrate the excess silverH2SO4, 98.08nitrate with 0.1 N ammonium thiocyanate VS.49.04 g in 1000 mL

Add slowly, with stirring, 27 mL of sulfuric acid to a suffi-cient quantity of water to make 1000 mL. Cool and stan-dardize against tromethamine as described under Hydrochlo-ric Acid, Normal (1 N).

Tetrabutylammonium Hydroxide, Tenth-Normal (0.1 N)Tetramethylammonium Chloride, Tenth-Molar (0.1 M)(C4H9)4NOH, 259.47

(CH3)4NCl, 109.6025.95 g in 1000 mL10.96 g in 1000 mLDissolve 40 g of tetra-n-butylammonium iodide in 90 mL

Dissolve 10.96 g of tetramethylammonium chloride inof anhydrous methanol in a glass-stoppered flask. Place inwater to make 1000 mL, and standardize the solution asan ice bath, add 20 g of powdered silver oxide, insert thefollows.stopper in the flask, and agitate vigorously for 60 minutes.

Transfer an accurately measured volume of about 40 mLCentrifuge a few mL, and test the supernatant for iodideof the solution to a flask, add 10 mL of diluted nitric acid(see Iodide ⟨191⟩). If the test is positive, add an additionaland 50.0 mL of 0.1 N silver nitrate VS, and mix. Add 5 mL2 g of silver oxide, and continue to allow to stand forof nitrobenzene and 2 mL of ferric ammonium sulfate TS,30 minutes with intermittent agitation. When all of the io-shake, and titrate the excess silver nitrate with 0.1 N ammo-dide has reacted, filter through a fine-porosity, sintered-glassnium thiocyanate VS.funnel. Rinse the flask and the funnel with three 50-mL por-

tions of anhydrous toluene, adding the rinsings to the fil-trate. Dilute with a mixture of three volumes of anhydroustoluene and 1 volume of anhydrous methanol to 1000 mL,and flush the solution for 10 minutes with dry, carbon diox-ide-free nitrogen. [NOTE—If necessary to obtain a clear solu-tion, further small quantities of anhydrous methanol may beadded.] Store in a reservoir protected from carbon dioxide Titanium Trichloride, Tenth-Normal (0.1 N)and moisture, and discard after 60 days. Alternatively, the TiCl3, 154.23solution may be prepared by diluting a suitable volume of 15.42 g in 1000 mLcommercially available tetrabutylammonium hydroxide solu- Add 75 mL of titanium trichloride solution (1 in 5) totion in methanol with a mixture of 4 volumes of anhydrous 75 mL of hydrochloric acid, dilute to 1000 mL, and mix.toluene and 1 volume of anhydrous methanol. [NOTE—If Standardize the solution as follows, using the special titra-necessary to obtain a clear solution, further small quantities tion apparatus described.of methanol may be added.] Apparatus—Store the titanium trichloride solution in the

Standardize the solution on the day of use as follows. reservoir of a closed-system titration apparatus in an atmos-Dissolve about 400 mg of primary standard benzoic acid, phere of hydrogen.

accurately weighed, in 80 mL of dimethylformamide, add Use a wide-mouth, 500-mL conical flask as the titration3 drops of a 1 in 100 solution of thymol blue in dimethyl- vessel, and connect it by means of a tight-fitting rubberformamide, and titrate to a blue endpoint with the tetrabu- stopper to the titration buret, an inlet tube for carbon diox-tylammonium hydroxide solution, delivering the titrant from ide, and an exit tube. Arrange for mechanical stirring. Alla buret equipped with a carbon dioxide absorption trap. joints must be air-tight. Arrange to have both the hydrogenPerform a blank determination, and make any necessary and the carbon dioxide pass through wash bottles contain-correction. Each mL of 0.1 N tetrabutylammonium hydrox- ing titanium trichloride solution (approximately 1 in 50) toide is equivalent to 12.21 mg of benzoic acid. remove any oxygen.

If the solution to be titrated is to be heated before orduring titration, connect the titration flask with an uprightreflux condenser through the rubber stopper.

Standardization—Place an accurately measured volume ofabout 40 mL of 0.1 N ferric ammonium sulfate VS in thetitration flask, and pass in a rapid stream of carbon dioxideuntil all the air has been removed. Add the titanium trichlo-Tetrabutylammonium Hydroxide in Methanol/ride solution from the buret until near the calculatedIsopropyl Alcohol, 0.1 Nendpoint (about 35 mL), then add through the outlet tubePrepare as described for Tetrabutylammonium Hydroxide,5 mL of ammonium thiocyanate TS, and continue the titra-Tenth-Normal (0.1 N) using isopropyl alcohol instead of tolu-tion until the solution is colorless.ene, and standardize as described. Alternatively, the solution

may be prepared by diluting a suitable volume of commer-cially available tetrabutylammonium hydroxide solution inmethanol with 4 volumes of anhydrous isopropyl alcohol.

Zinc Sulfate, Twentieth-Molar (0.05 M)ZnSO4 · 7H2O, 287.56

14.4 g in 1000 mL

USP 36 Reagents / Chromatographic Columns 1227

Dissolve 14.4 g of zinc sulfate in water to make 1 L. Stan- 50 mL of alcohol, and 2 mL of dithizone TS. Titrate with thedardize the solution as follows. zinc sulfate solution to a clear, rose-pink color.

Accurately measure about 10 mL of 0.05 M edetate diso-dium VS into a 125-mL conical flask, and add, in the ordergiven, 10 mL of acetic acid–ammonium acetate buffer TS,

Chromatographic ColumnsThe following list of packings (L), phases (G), and sup- L19—Strong cation-exchange resin consisting of

ports (S) is intended to be a convenient reference for the sulfonated cross-linked styrene-divinylbenzene copolymer inchromatographer. [NOTE—Particle sizes given in this listing the calcium form, about 9 µm in diameter.are those generally provided. Where other, usually finer, L20—Dihydroxypropane groups chemically bonded to po-sizes are required, the individual monograph specifies the rous silica or hybrid particles, 1.5 to 10 µm in diameter.desired particle size. Within any category of packings or L21—A rigid, spherical styrene-divinylbenzene copolymerphases listed below, there may be a wide range of columns 3 to 10 µm in diameter.available. Where it is necessary to define more specifically L22—A cation-exchange resin made of porous polystyrenethe chromatographic conditions, the individual monograph gel with sulfonic acid groups, about 10 µm in size.so indicates.] L23—An anion-exchange resin made of porous

polymethacrylate or polyacrylate gel with quaternary ammo-nium groups, 7–12 µm in size.Packings L24—A semi-rigid hydrophilic gel consisting of vinylpolymers with numerous hydroxyl groups on the matrix sur-L1—Octadecyl silane chemically bonded to porous or face, 32 to 63 µm in diameter. [NOTE—Available as YMC-nonporous silica or ceramic microparticles, 1.5 to 10 µm in Pack PVA-SIL manufactured by YMC Co., Ltd. and distrib-diameter, or a monolithic silica rod. uted by Waters Corp. (www.waters.com).]L2—Octadecyl silane chemically bonded to silica gel of a L25—Packing having the capacity to separate compoundscontrolled surface porosity that has been bonded to a solid with a molecular weight range from 100–5000 (as deter-spherical core, 30 to 50 µm in diameter. mined by polyethylene oxide), applied to neutral, anionic,L3—Porous silica particles, 1.5 to 10 µm in diameter, or a and cationic water-soluble polymers. A polymethacrylatemonolithic silica rod. resin base, cross-linked with polyhydroxylated ether (surfaceL4—Silica gel of controlled surface porosity bonded to a contained some residual carboxyl functional groups) wassolid spherical core, 30 to 50 µm in diameter. found suitable.L5—Alumina of controlled surface porosity bonded to a L26—Butyl silane chemically bonded to totally porous sil-solid spherical core, 30 to 50 µm in diameter. ica particles, 1.5 to 10 µm in diameter.L6—Strong cation-exchange packing–sulfonated fluoro- L27—Porous silica particles, 30 to 50 µm in diameter.carbon polymer coated on a solid spherical core, 30 to L28—A multifunctional support, which consists of a high50 µm in diameter. purity, 100 A, spherical silica substrate that has beenL7—Octylsilane chemically bonded to totally porous or bonded with anionic exchanger, amine functionality in addi-superficially porous silica particles, 1.5–10 µm in diameter, tion to a conventional reversed phase C8 functionality.or a monolithic silica rod. L29—Gamma alumina, reverse-phase, low carbon per-L8—An essentially monomolecular layer of aminopropylsi- centage by weight, alumina-based polybutadiene sphericallane chemically bonded to totally porous silica gel support, particles, 5 µm in diameter with a pore volume of 80 A.1.5 to 10 µm in diameter. L30—Ethyl silane chemically bonded to totally porous sil-L9—Irregular or spherical, totally porous silica gel having ica particles, 3 to 10 µm in diameter.a chemically bonded, strongly acidic cation-exchange coat- L31—A hydroxide-selective, strong anion-exchange resin-ing, 3 to 10 µm in diameter. quaternary amine bonded on latex particles attached to aL10—Nitrile groups chemically bonded to porous silica core of 8.5-µm macroporous particles having a pore size ofparticles, 1.5 to 10 µm in diameter. 2000 A and consisting of ethylvinylbenzene cross-linkedL11—Phenyl groups chemically bonded to porous silica with 55% divinylbenzene.particles, 1.5 to 10 µm in diameter. L32—A chiral ligand-exchange packing–L-proline copperL12—A strong anion-exchange packing made by chemi- complex covalently bonded to irregularly shaped silica parti-cally bonding a quaternary amine to a solid silica spherical cles, 5 to 10 µm in diameter.core, 30 to 50 µm in diameter. L33—Packing having the capacity to separate dextrans byL13—Trimethylsilane chemically bonded to porous silica molecular size over a range of 4,000 to 500,000 Da. It isparticles, 3 to 10 µm in diameter. spherical, silica-based, and processed to provide pH stability.L14—Silica gel having a chemically bonded, strongly basic [NOTE—Available as TSK-GEL G4000SWxl from Tosoh Bio-quaternary ammonium anion-exchange coating, 5 to 10 µm science (www.tosohbioscience.com).]in diameter. L34—Strong cation-exchange resin consisting ofL15—Hexylsilane chemically bonded to totally porous sil- sulfonated cross-linked styrene–divinylbenzene copolymer inica particles, 3 to 10 µm in diameter. the lead form, 7 to 9 µm in diameter.L16—Dimethylsilane chemically bonded to porous silica L35—A zirconium-stabilized spherical silica packing with aparticles, 5 to 10 µm in diameter. hydrophilic (diol-type) molecular monolayer bonded phaseL17—Strong cation-exchange resin consisting of having a pore size of 150 A.sulfonated cross-linked styrene–divinylbenzene copolymer in L36—A 3,5-dinitrobenzoyl derivative of L-phenylglycinethe hydrogen form, 6 to 12 µm in diameter. covalently bonded to 5-µm aminopropyl silica.L18—Amino and cyano groups chemically bonded to po- L37—Packing having the capacity to separate proteins byrous silica particles, 3 to 10 µm in diameter. molecular size over a range of 2,000 to 40,000 Da. It is apolymethacrylate gel.

1228 Chromatographic Columns / Reagents USP 36

L38—A methacrylate-based size-exclusion packing for the sodium form, about 6 to 30 µm in diameter. [NOTE—water-soluble samples. Available as Aminex HPX-87N from Bio-Rad Laboratories,

L39—A hydrophilic polyhydroxymethacrylate gel of totally (2000/01 catalog, #125-0143) www.bio-rad.com.]porous spherical resin. L59—Packing for the size-exclusion separation of proteins

L40—Cellulose tris-3,5-dimethylphenylcarbamate coated (separation by molecular weight) over the range of 5 toporous silica particles, 5 to 20 µm in diameter. 7000 kDa. The packing is a spherical 1.5- to 10-µm silica or

L41—Immobilized α1-acid glycoprotein on spherical silica hybrid packing with a hydrophilic coating.particles, 5 µm in diameter. L60—Spherical, porous silica gel, 10 µm or less in diame-

L42—Octylsilane and octadecylsilane groups chemically ter, the surface of which has been covalently modified withbonded to porous silica particles, 5 µm in diameter. alkyl amide groups and endcapped. [NOTE—Available as

L43—Pentafluorophenyl groups chemically bonded to sil- Supelcosil LC-ABZ from Supelco (www.sigmaaldrich.com/ica particles by a propyl spacer, 1.5 to 10 µm in diameter. supelco).]

L44—A multifunctional support, which consists of a high L61—A hydroxide selective strong anion-exchange resinpurity, 60 A, spherical silica substrate that has been bonded consisting of a highly cross-linked core of 13-µm micro-with a cationic exchanger, sulfonic acid functionality in ad- porous particles having a pore size less than 10 A units anddition to a conventional reversed phase C8 functionality. consisting of ethylvinylbenzene cross-linked with 55%

L45—Beta cyclodextrin bonded to porous silica particles, divinylbenzene with a latex coating composed of 85-nm di-5 to 10 µm in diameter. ameter microbeads bonded with alkanol quaternary ammo-

L46—Polystyrene/divinylbenzene substrate agglomerated nium ions (6%). [NOTE—Available as Ion Pac AS-11 and AG-with quaternary amine functionalized latex beads, about 9 11 from Dionex (www.dionex.com).]to 11 µm in diameter. L62—C30 silane bonded phase on a fully porous spherical

L47—High-capacity anion-exchange microporous sub- silica, 3 to 15 µm in diameter.strate, fully functionalized with trimethlyamine groups, 8 µm L63—Glycopeptide teicoplanin linked through multiplein diameter. [NOTE—Available as CarboPac MA1 and distrib- covalent bonds to a 100-A units spherical silica.uted by Dionex Corp. (www.dionex.com).] [NOTE—Available as Astec Chirobiotic T from Supelco (www.

L48—Sulfonated, cross-linked polystyrene with an outer sigmaaldrich.com).]layer of submicron, porous, anion-exchange microbeads, 10 L64—Strongly basic anion-exchange resin consisting ofto 15 µm in diameter. 8% cross-linked styrene-divinylbenzene copolymer with a

L49—A reversed-phase packing made by coating a thin quaternary ammonium group in the chloride form, 45 tolayer of polybutadiene onto spherical porous zirconia parti- 180 µm in diameter. [NOTE—A suitable grade is available ascles, 3 to 10 µm in diameter. [NOTE—Available as Zirchrom AG 1-X8 resin chloride form from www.discover.bio-rad.PBD from www.zirchrom.com.] com.]

L50—Multifunction resin with reversed-phase retention L65—Strongly acidic cation-exchange resin consisting ofand strong anion-exchange functionalities. The resin consists 8% sulfonated cross-linked styrene-divinylbenzene co-of ethylvinylbenzene, 55% cross-linked with divinylbenzene polymer with a sulfonic acid group in the hydrogen form,copolymer, 3 to 15 µm in diameter, and a surface area not 45 to 250 µm in diameter. [NOTE—A suitable grade is availa-less than 350 m2 per g. Substrate is coated with quaternary ble as AG 50W-X2 resin hydrogen form fromammonium functionalized latex particles consisting of sty- www.discover.bio-rad.com.]rene cross-linked with divinylbenzene. [NOTE—Available as L66—A crown ether coated on a 5-µm particle size silicaOmniPac PAX-500 and distributed by Dionex Corp. (www. gel substrate. The active site is (S)-18-crown-6-ether.dionex.com).] [NOTE—Available as Crownpak CR(+) from Daicel

L51—Amylose tris-3,5-dimethylphenylcarbamate-coated, (www.daicel.com).]porous, spherical, silica particles, 5 to 10 µm in diameter. L67—Porous vinyl alcohol copolymer with a C18 alkyl[NOTE—Available as Chiralpak AD from Chiral Technologies, group attached to the hydroxyl group of the polymer, 2 toInc., (www.chiraltech.com).] 10 µm in diameter. [NOTE—Available as apHera C18 from

L52—A strong cation-exchange resin made of porous sil- Supelco (www.sigmaaldrich.com).]ica with sulfopropyl groups, 5 to 10 µm in diameter. L68—Spherical, porous silica, 10 µm or less in diameter,[NOTE—Available as TSK-GEL IC-Cation-SW from Tosoh Bio- the surface of which has been covalently modified with alkylscience (www.tosohbioscience.com).] amide groups and not endcapped. [NOTE—Available as

L53—Weak cation-exchange resin consisting of SUPELCOSIL SUPLEX pKb-100 from Supelcoethylvinylbenzene, 55% cross-linked with divinylbenzene co- (www.sigmaaldrich.com).]polymer, 3 to 15 µm diameter. Substrate is surface grafted L69—Ethylvinylbenzene/divinylbenzene substrate agglom-with carboxylic acid and/or phosphoric acid functionalized erated with quaternary amine functionalized 130-nm latexmonomers. Capacity not less than 500 µEq/column. [NOTE— beads, about 6.5 µm in diameter. [NOTE—Available asAvailable as IonPac CS14 distributed by Dionex Corp. CarboPac PA20 from www.dionex.com.](www.dionex.com).] L70—Cellulose tris(phenyl carbamate) coated on 5-µm sil-

L54—A size exclusion medium made of covalent bonding ica. [NOTE—Available as Chiralcel OC-H from www.of dextran to highly cross-linked porous agarose beads, chiraltech.com.]about 13 µm in diameter. L71—A rigid, spherical polymetacrylate, 4 to 6 µm in di-

[NOTE—Available as Superdex Peptide HR 10/30 from ameter. [NOTE—Available as RSpak DE-613 from www.www.gelifesciences.com.] shodex.com.]

L55—A strong cation-exchange resin made of porous sil- L72—(S)-phenylglycine and 3,5-dinitroanaline urea link-ica coated with polybutadiene–maleic acid copolymer, age covalently bonded to silica.about 5 µm in diameter. [NOTE—Available as IC-Pak C M/D [NOTE—Available as Sumichiral OA-3300, distributed byfrom Waters Corp. (www.waters.com).] www.phenomenex.com.]

L56—Propyl silane chemically bonded to totally porous L73—A rigid spherical polydivinylbenzene particle, 5 tosilica particles, 3 to 10 µm in diameter. [NOTE—Available as 10 µm in diameter. [NOTE—Available as Jordi-Gel DBV fromZorbax SB-C3 from Agilent Technologies (www.agilent.com/ www.jordiflp.com.]chem).] L74—a strong anion-exchange resin consisting of a highly

L57—A chiral-recognition protein, ovomucoid, chemically cross-linked core of 7-µm macroporous particles having abonded to silica particles, about 5 µm in diameter, with a 100-A average pore size and consisting of ethylvinylbenzenepore size of 120 A. [NOTE—Available as Ultron ES-OVM cross-linked with 55% divinylbenzene and an anion-ex-from Agilent Technologies (www.agilent.com/chem).] change layer grafted to the surface, which is functionalized

L58—Strong cation-exchange resin consisting of with alkyl quaternary ammonium ions. [NOTE—Available assulfonated cross-linked styrene-divinylbenzene copolymer in IonPac AS14A from Dionex (www.dionex.com).]

USP 36 Reagents / Chromatographic Columns 1229

L75—A chiral-recognition protein, bovine serum albumine G39—Polyethylene glycol (av. mol. wt. about 1500).(BSA), chemically bonded to silica particles, about 7 µm in G40—Ethylene glycol adipate.diameter, with a pore size of 300 A. G41—Phenylmethyldimethylsilicone (10% phenyl-substi-

tuted).G42—35% phenyl-65% dimethylpolysiloxane (percent-Phases ages refer to molar substitution).G43—6% cyanopropylphenyl-94% dimethylpolysiloxaneG1—Dimethylpolysiloxane oil. (percentages refer to molar substitution).G2—Dimethylpolysiloxane gum. G44—2% low molecular weight petrolatum hydrocarbonG3—50% Phenyl-50% methylpolysiloxane. grease and 1% solution of potassium hydroxide.G4—Diethylene glycol succinate polyester. G45—Divinylbenzene-ethylene glycol-dimethylacrylate.G5—3-Cyanopropylpolysiloxane. G46—14% Cyanopropylphenyl-86% methylpolysiloxane.G6—Trifluoropropylmethylpolysiloxane. G47—Polyethylene glycol (av. mol. wt. of about 8000).G7—50% 3-Cyanopropyl-50% phenylmethylsilicone. G48—Highly polar, partially cross-linked cyanopolysilox-G8—80% Bis(3-cyanopropyl)-20% 3-cya- ane.nopropylphenylpoly-siloxane (percentages refer to molar

substitution).G9—Methylvinylpolysiloxane. SupportsG10—Polyamide formed by reacting a C36 dicarboxylic

acid with 1,3-di-4-piperidylpropane and piperidine in the re- [NOTE—Unless otherwise specified, mesh sizes of 80 tospective mole ratios of 1.00:0.90:0.20. 100 or, alternatively, 100 to 120 are intended.]

G11—Bis(2-ethylhexyl) sebacate polyester. S1A—Siliceous earth for gas chromatography has beenG12—Phenyldiethanolamine succinate polyester. flux-calcined by mixing diatomite with Na2CO3 flux and cal-G13—Sorbitol. cining above 900°. The siliceous earth is acid-washed, thenG14—Polyethylene glycol (av. mol. wt. of 950 to 1050). water-washed until neutral, but not base-washed. The sili-G15—Polyethylene glycol (av. mol. wt. of 3000 to 3700). ceous earth may be silanized by treating with an agent suchG16—Polyethylene glycol compound (av. mol. wt. about as dimethyldichlorosilane [NOTE—Unless otherwise specified

15,000). A high molecular weight compound of polyethyl- in the individual monograph, silanized support is intended.]ene glycol with a diepoxide linker. [NOTE—Available com- to mask surface silanol groups.mercially as Polyethylene Glycol Compound 20M, or as S1AB—The siliceous earth as described above is bothCarbowax 20M, from suppliers of chromatographic acid- and base-washed. [NOTE—Unless otherwise specified inreagents.] the individual monograph, silanized support is intended.]

G17—75% Phenyl-25% methylpolysiloxane. S1C—A support prepared from crushed firebrick and cal-G18—Polyalkylene glycol. cined or burned with a clay binder above 900° with subse-G19—25% Phenyl-25% cyanopropyl-50% methylsilicone. quent acid-wash. It may be silanized.G20—Polyethylene glycol (av. mol. wt. of 380 to 420). S1NS—The siliceous earth is untreated.G21—Neopentyl glycol succinate. S2—Styrene-divinylbenzene copolymer having a nominalG22—Bis(2-ethylhexyl) phthalate. surface area of less than 50 m2 per g and an average poreG23—Polyethylene glycol adipate. diameter of 0.3 to 0.4 µm.G24—Diisodecyl phthalate. S3—Copolymer of ethylvinylbenzene and divinylbenzeneG25—Polyethylene glycol compound TPA. A high molecu- having a nominal surface area of 500 to 600 m2 per g and

lar weight compound of a polyethylene glycol and a diepo- an average pore diameter of 0.0075 µm.xide that is esterified with terephthalic acid. S4—Styrene-divinylbenzene copolymer with aromatic –O

[NOTE—Available commercially as Carbowax 20M-TPA and –N groups, having a nominal surface area of 400 tofrom suppliers of chromatographic reagents.] 600 m2 per g and an average pore diameter of 0.0076 µm.

G26—25% 2-Cyanoethyl-75% methylpolysiloxane. S5—40- to 60-mesh, high-molecular weight tetrafluoreth-G27—5% Phenyl-95% methylpolysiloxane. ylene polymer.G28—25% Phenyl-75% methylpolysiloxane. S6—Styrene-divinylbenzene copolymer having a nominalG29—3,3′-Thiodipropionitrile. surface area of 250 to 350 m2 per g and an average poreG30—Tetraethylene glycol dimethyl ether. diameter of 0.0091 µm.G31—Nonylphenoxypoly(ethyleneoxy)ethanol (av. S7—Graphitized carbon having a nominal surface area of

ethyleneoxy chain length is 30); Nonoxynol 30. 12 m2 per g.G32—20% Phenylmethyl-80% dimethylpolysiloxane. S8—Copolymer of 4-vinyl-pyridine and styrene-G33—20% Carborane-80% methylsilicone. divinylbenzene.G34—Diethylene glycol succinate polyester stabilized with S9—A porous polymer based on 2,6-diphenyl-p-phenyl-

phosphoric acid. ene oxide.G35—A high molecular weight compound of a polyethyl- S10—A highly polar cross-linked copolymer of acryloni-

ene glycol and a diepoxide that is esterified with nitroter- trite and divinylbenzene.ephthalic acid. S11—Graphitized carbon having a nominal surface area of

G36—1% Vinyl-5% phenylmethylpolysiloxane. 100 m2 per g modified with small amounts of petrolatumG37—Polyimide. and polyethylene glycol compound.G38—Phase G1 containing a small percentage of a tailing S12—Graphitized carbon having a nominal surface area of

inhibitor. 100 m2 per g.[NOTE—A suitable grade is available commercially as

“SP2100/0.1% Carbowax 1500” from Supelco, Inc. (www.sigmaaldrich.com/supelco).]

Reagents, Indicators and Solutions

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