APPLICATION NOTES - labtechsrl.com€¦ · SPE for EPA 608 for Organochlorine Pesticides and...

Sepaths Sample Preparation Systems

APPLICATION NOTES

LABTECH S.r.l.

Sepaths Application book

pag. 2

CONTENT

Carbaryl in Tap Water by Sepaths-6 SPE/HPLC……………………………………………...pag.3

Organochlorine Pesticides Residue in Tap Water by Sepaths-6 SPE/GC-ECD………………pag.8

SPE for Nitrosamines in Water...........................................................................................…...pag.14

SPE for EPA 608 for Organochlorine Pesticides and PCB’s………………………………….pag.15

SPE for EPA 625 for Semivolatile Organics in Wastewaters…………………………………pag.16

Method for Total Petroleum Hydrocarbon in Water…………………………………………..pag.17

SPE for EPA 1664 for Oil and Grease in Waters……………………………………………...pag.18

Organophosphorus Pesticide Monocrotophos in Tap Water by Sepaths SPE/HPLC…………pag.20

Polycyclic Aromatic Hydrocarbons (PAHs) in Tap Water with Sepaths SPE/HPLC…………pag.22

Pyrethroids in Tap Water by Sepaths SPE/HPLC……………………………………………...pag.25

Grease and Oil in Water by Sepaths SPE/Gravimetric Method………………………………..pag.27

Bisphenol A in Water by Extrapid-Rapidisk-HPLC………………………...…………………pag.29

Phthalic Acid Esters in Water by Extrapid-Rapidisk-HPLC…………………………………..pag.31

Carbamate Pesticides in Wheat Flour by Extrapid SPE-HPLC………………………………..pag.33


pag. 3

Determination of Carbaryl in Tap Water by Sepaths-6

SPE/HPLC

LabTech, Inc.

Carbaryl (1-naphthyl methylcarbamate) is a widely used insecticide in the recent 20 years.

The pesticide residue from the environment damages blood system, nerve system, and

reproductive system of human beings. In several countries such as Britain, Australia and

Germany, Carbaryl has been added into prohibited pesticides list.

For the concentration of Carbaryl in drinking water the United State Environmental

Protection Agency (US EPA) have strict limit.

High-performance liquid chromatography (HPLC), the conventional method of Carbaryl

detection, is time-consuming and laborious.

With Sepath®Automated solid-phase extraction (SPE) system and SPE disks, the

efficiency has been greatly increased, saving considerably time and labor.

This study develops one application of Carbaryl detection in water by pretreating the tap

water sample via SPE, and analyzing by HPLC. This method shows a great recovery with

facilitated operation.

1. Experimental

1.1 Instrumentation and Materials

Sepaths-6 Automated SPE System (LabTech Ltd.)

Methanol

Rapidisk C18 47 mm SPE disk (LabTech. Ltd.)

HPLC System coupled with UV detector

Flow rate: 1 mL / min

Mobile phase: Methanol / Water (v / v) 65 / 35

Column: Ultimate C18 (4.6 mm × 250 mm, 5 μm)

Column Temperature: 35° C

Sample Volume: 20 μL

Wavelength: 280 nm


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1.2 Method Summary

1) 1000 mL water samples

2) Add 40 mL 0.8 ppm carbaryl standard solution to the sample

3) Fix the sample bottle onto the Sepaths-6 Automated SPE Module with the

Rapidisk C18 SPE disk.

4) Place the 40 mL collection vials into the Sepaths collection window

5) Load and Run the method listed in table 1

6) Once the method is completed, take the collection vials rack with the eluted phases

7) Add Methanol to the eluted phases up to 40 mL

8) Analyze with HPLC system

1.3 SPE Method

Step Solvent Soak Time Volume Dry Time

Prewet 1 Methanol 1 min 5 mL 30 sec

Prewet Methanol 1 min 5 mL 30 sec

Prewet Reagent Water 5 sec 5 mL 2 sec

Prewet Reagent Water 5 sec 5 mL 2 sec

Process Sample

Air Dry 2:00 min

Rinse 1 Methanol 2 min 5 mL 20 sec

Rinse 2 Methanol 30 sec 5 mL 20 sec

Rinse 3 Methanol 30 sec 5 mL 20 sec

Rinse 4 Methanol 30 sec 5 mL 1 min

Table 1. SPE method of carbaryl by Sepaths-6 ® Automated SPE system

The method process takes 35 min to compleatly extract No.6 samples (1 L volume).

Compared with single-channel or manual SPE systems, the efficiency of Sepaths-6

Automated SPE system has been greatly enhanced for the following reasons :

1) 6 samples extracted at the same time

2) No cross contamination

3) Reproducibility of the method

4) High Flow stability/accuracy thanks to Nitrogen positive pressure


pag. 5

2. Results

2.1 Chromatogram of Standard, Control, and Spiked Sample Solutions

Figure 1. HPLC chromatogram of carbaryl standard.

Figure 2. HPLC chromatogram oftap water after SPE.


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Figure 3. HPLC chromatogram of tap water spiked with carbaryl.


pag. 7

2.2 Recovery of Carbaryl Spiked Water Samples

To determine the precision of our system, 20 spiked tap water samples were analyzed by

HPLC. 1 L tap water samples were spiked at a concentration of 0.8 mg/L with carbaryl

standard. After extracted by Sepaths-6 Automated SPE system, the extracts were diluted

with methanol to 40 mL.Recovery was calculated by comparing the ratio(s) of analyte peak

areas.

Test Number Standard Spiked

(mg/L)

Analyzed Result

(mg/L) Recovery (%)

Avg. Recovery

(%) RSD

1

0.8

0.6983 87.29

93.50 6.04

2 0.7271 90.89

3 0.7321 91.51

4 0.7244 90.55

5 0.6902 86.27

6 0.7598 94.97

7 0.6833 85.41

8 0.6975 87.19

9 0.7762 97.03

10 0.7781 97.26

11 0.7802 97.52

12 0.7866 98.33

13 0.7349 91.86

14 0.7310 91.37

15 0.7310 89.12

16 0.8217 102.71

17 0.8300 103.75

18 0.7998 99.98

3. Conclusion

This study develops a method of Carbaryl extraction via Sepaths-6 automated SPE system

coupled with HPLC-UV analysis. This method has good recovery (mean recovery 93.5 %)

and the great repeatability (RSD 6.04 %). The results illustrate the reliability of this method

and the efficiency of Sepaths instrument as fast ans easy to use SPE system.


pag. 8

Determination of Organochlorine Pesticides Residue in Tap

Water by Sepaths-6 SPE/GC-ECD

LabTech, Inc.

Organochlorine pesticides is a broad-spectrum, high efficient, inexpensive pesticides,

which were widely used worldwide.

However, the strong stability makes organochlorine pesticides accumulate largely through

the food chain, which eventually influences human beings health. Because of its strong

stability, long half-life, the organochlorinepesticides residue exceeded maximum residue

limit (MRL) happens frequently.

This study develops a method to determine organochlorine pesticides residue in tap water

by using solid phase extraction(SPE) coupled with gas chromatography-electron capture

detection(GC-ECD). This method shows great recovery and easy operation.

1. Experimental


Sepaths-6® Automated SPE System (LabTech. Ltd.)

GC-ECD

DryDisk Solvent Drying System (SDS 101)

Nitrogen Evaporator

Methanol

Ethyl Acetate

n-Hexane

SPE disk


pag. 9

1.2 Method Summary

1) 1000 mL water samples

2) Fix the sample bottle onto the Sepaths-6 Automated SPE Module with the

Rapidisk C18 SPE disk.

4) Place the 40 mL collection vials into the Sepaths collection window

5) Load and Run the method listed in table 1

6) Once the method is completed, take the collection vials rack with the eluted phases

8) Analyze with GC-ECD

1.3 SPE Method

Step Solvent Soak Time Volume Dry Time

Prewet 1 Hexane 3 min 10 mL 0 min

Prewet 2 Methanol 2 min 5 mL 0 min

Prewet 3 Reagent Water 0 min 5 mL 0 min

Process Sample 1 L

Wash 1 Reagent Water -- 10 mL 2 min

Rinse 1 Ethyl Acetate 2 min 7 mL 1 min

Rinse 2 Ethyl Acetate 2 min 7 mL 1 min

Rinse 3 Hexane 2 min 8 mL 1 min

Rinse 4 Hexane 2 min 8 mL 2 min Table 1. Extract method of carbaryl by Sepaths-6 ® Automated SPE system.

The collected extracts from Sepaths-6 Automated SPE system were placed under the

Sepath-C Nitrogen Evaporators,evaporated by N2 till 1.0 mL at 40°C prior to analysis.

1.4 Apparatus

GC-ECD Method :

Column：TM-Pesticide 1 30m×0.53mm×1.0um

Oven Temperature: The initial temperature was 180℃ for 4 minutes, which was increased

to 220℃ at 5℃/min.Then this temperature was held for 6 min.

Injection Temperature: 220℃ ; Detection Temperature: 280℃

Sample Volume: 2μL ; Split Ratio: Splitless


pag. 10

Figure 1. Chromatogram of 8 kinds of Organochlorine Pesticides on GC-ECD.

2. Results and Discussion

2.1 Calibration Curve and Limit of Detection

Figure 2. Calibration curves of 8 kinds of Organochlorine Pesticides.


pag. 11

From these plots, the linear range is 10 ppb-150 ppb. The equations are listed below,

where x is sample concentration, y is peak area.

α -666 y = 9.0287x – 21.465 R2 = 0.9996

β -666 y = 8.3155x – 15.119 R2 = 0.9993

γ -666 y = 2.4953x + 120.71 R2 = 0.9965

δ -666 y = 8.4382x – 8.5691 R2 = 0.9994

P,P-DDT y = 8.655x – 57.722 R2 = 0.9958

O,P-DDT y = 3.2334x + 7.0878 R2 = 0.9960

P,P-DDE y = 6.0085x – 14.612 R2 = 0.9922

P,P-DDD y = 2.8035x + 46.326 R2 = 0.9903

Figure 3. Chromatogram of 8 kinds of Organochlorine Pesticides standard in tap water on GC-ECD.

The accuracy of our method was evaluated by additive recycle experiments. The results of

the organic chlorine pesticide were displayed in Table 1.


pag. 12

Standard (mg/g) Measured (mg/g) Recovery (%)

1 α-666 200 213.98 106.99

203.14 101.57

193.12 96.56

188.99 94.50

197.33 98.67

2 β-666 200 217.55 108.78

209.90 104.95

185.01 92.51

203.17 101.58

197.28 98.64

3 γ-666 200 204.17 102.08

212.70 106.35

175.88 87.94

268.29 134.14

192.87 96.44

4 δ-666 200 225.73 112.86

198.83 99.42

207.51 103.76

226.37 113.19

191.61 95.81

5 P,P-DDT 200 201.37 100.69

223.85 111.92

197.03 98.51

192.93 96.46

194.91 97.45

6 O,P-DDT 200 175.30 87.65

210.62 105.31

208.16 104.08

206.97 103.49

215.77 107.88

7 P,P-DDE 200 215.04 107.52

185.83 92.91

179.48 89.74

209.34 104.67

203.70 101.85

8 P,P-DDD 200 194.17 97.09

209.35 104.67

233.77 116.89

214.22 107.11

194.15 97.07 Table 1. The Recovery of Organochlorine Pesticides in Tap Water.

The water samples were spiked with one kind of organochlorine pesticide, extracted via SPE, then analysis by GC-ECD three times continuously. The results of peak area on the below table No.2 shows the recovery and RSD of 8 kinds of organochlorine pesticides.


pag. 13

Item α-666 β-666 γ-666 δ-666 P,P-DDT O,P-DDT P,P-DDE P,P-DDD

1 3785.448 3009.495 1349.540 2960.282 2129.499 923.274 1871.482 1126.737

2 3844.901 3158.502 1435.250 2942.996 2383.406 972.279 1739.195 1179.389

3 3922.923 3050.534 1313.259 3103.537 2647.132 1084.909 1715.599 1355.31

4 3727.606 3102.758 1475.507 3042.421 2215.406 959.252 1853.438 1279.078

5 3140.690 2531.451 1189.939 2293.325 2145.536 889.795 1705.439 1062.449

RSD

(%) 8.48 8.48 8.26 11.43 9.40 7.65 4.46 9.77

Table 2. The RSD of Organochlorine Pesticides in Tap Water.

Figure 3. Chromatogram of 8 kinds of organochlorine pesticides spiked in tap water on GC-ECD after SPE.

3. Conclusion

This study develops a method for organochlorine pesticides detection by Sepaths-6

automated SPE system, followed by GC-ECD analysis. The mean recoveries of 8 kinds

organochlorine pesticides are 80.19 % - 91.98 %, and the RSD are less than 7.7 %. The

results illustrate the reliability of this method and the efficiency of Sepaths instrument as

fast ans easy to use SPE system.


pag. 14

SPE for Nitrosamines in Water

Introduction:

Due to the carcinogenic nature of nitrosamines at very low levels, new regulations setting

detection limits at PPT (ng/L) levels have been set for nitrosamines in drinking water, milk,

beer, and food products. EPA Method 521 recommends coconut carbon SPE cartridges

and this method can be easily adapted for the analysis of food and beverages.

Reference method:

SPE cartridge: Coconut Carbon, 2g, 6 mL

Analytes: NDMA, NMEA, NDEA, NDPA, NMOR, NPYR, NPIP, NDBA and DPhA

LabTech SPE instrument:

Sepaths (automatic)

SPE method:

Cartridge Condition and wash:

(1) Dichloromethane, 5 mL, condition cartridge then drain to waste

(2) MTBE, 5 mL, condition cartridge then drain to waste

(3) DI water, 5 mL, wash cartridge then drain to waste

Sample Loading:

(1) 1000 mL

(2) Wash sample bottle with 10 mL of DI water

Wash and Eluting:

(1) Dichloromethane, 5 mL, wash cartridge then drain to collect

(2) Dry cartridge for 20 min

(3) Dichloromethane, 5 mL, elution cartridge


pag. 15

SPE for EPA 608 for Organochlorine Pesticides and PCB’s

Reference method:

SPE cartridge: C18, 6 mL

Analytes: Organochlorine Pesticides and PCBs


Sepaths (automatic)

SPE method:


(1) Reagent Water, 5 mL, wash cartridge then drain to waste

(2) Methanol, 3 mL, wash cartridge then drain to waste

(3) Ethyl acetate, 5 mL, wash cartridge then drain to waste

Sample Loading:

(1) 550 mL

(2) Drying for 5 min

Eluting:

(1) Dichloromethane, 5 mL, soak for 30 sec then drain to collect


pag. 16

SPE for EPA 625 for Semivolatile Organics in Wastewaters

Reference method:

SPE cartridge: C18, 6 mL

Analytes: Organics Compounds

Note: Add 2,5 mL methanol and 2 mL concentrated sulfuric acid to 500 mL of sample


Sepaths (automatic)

SPE method:


(1) Methanol, 2 mL, wash cartridge then drain to waste

(2) Ethyl acetate and Dichloromethane, 5 mL, wash cartridge then drain to waste

(3) Methanol and water, 10 mL, condition cartridge then drain to waste

Sample Loading:

(1) 550 mL

(2) Drying for 10 min

Eluting:

(1) Ethyl acetate, 5 mL, soak for 30 sec then drain to collect

(2) Dichloromethane, 2 mL, soak for 30 sec then drain to collect


pag. 17

Method for Total Petroleum Hydrocarbon in Water

Reference method:

SPE Disk: DVB sorbent or C18, 47 mm

Analytes: Total Petroleum Hydrocarbons


Sepaths (automatic)

Extrapid (manual)

SPE method:

Disk Conditioning:

(1) Methylene Chloride, 7 mL, soak for 1 min then drain to waste

(2) Methanol, 7 mL, soak for 1 min then drain to waste

Keep the C18 disk, if used, wet during and after conditioning

Sample Loading:

(1) 500 mL -1000 mL

(2) Dry for 5 min

Eluting:

(1) Acetone, 7 mL, rinses the empty bottle then transferred to the disk, soaks for 0.5 min

then drain to collect

(2) Methylene Chloride, 7 mL, soak for 1 min then drain to collect




pag. 18

SPE for EPA 1664 – Oil and Grease in Waters

Introduction:

This method describes how to apply SPE for the EPA 1664A using LabTech equipment for

manifold SPE (Extrapid) or automatic SPE (Sepaths). SPE is permitted from the EPA

method as alernative to liquid-liquid hexane extraction ensuring up to 40% of solvent

saving and up to 50% of time saving (using Sepaths compared to LLE). The extract is

dried with sodium sulfate, hexane is evaporated and the residue is weighed and reported

in mg/L as HEM (N-Hexane Extractable Material)

Reference method:

SPE disks: LabTech, C18, 47mm

Analytes: N-Hexane Extractable Material (HEM)

Note : The pH level of the sample solution must be adjusted to 2 with acid solution

before to perform the SPE process


Sepaths (automatic)

Extrapid (manifold)

SPE method:

System and cartridge Pre-condition

(1) N-Hexane, 20 mL, precondition disks then drain to waste

(2) N-Hexane, 20 mL, second precondition then drain to waste and Dry for 1 minute

Disks Condition and Wash:

(1) Methanol, 10 mL, condition disks, soak for 1 minute then drain to waste

(2) DI water, 30 mL, wash disks then drain to waste

Note : Do not allow the disk to dry during Condition ad Wash steps


pag. 19

Sample Loading:

(1) 1000 mL of sample solution adjusted to pH 2

Dry and Eluting:

(1) Dry disks for 2 minutes

(2) Wash sample bottle with 10 mL of Hexane, soak disks for 2 minutes then collect in the

elution position

(3) Repeat the above step

(3) Hexane, 10 mL, elute disks then dry for 5 minutes

The eluate is then dried using Anhydrous Sodium Sulfate. Add 5 g of Sulfate on a funnel

with glass wool on the bottom, then pour the eluate on the funnel and collect in a

previously weighed clean vial. Rinse the funnel and the Sodium Sulfate with 10 mL of

Hexane and collect in the same vial.

The last step is the Hexane evaporation. When Hexane is evaporated, weight the vial and

calculate the HEM quantity in mg/L


pag. 20

Determination of Organophosphorus Pesticide

Monocrotophos in Tap Water by Sepaths Automated SPE

extraction System

LabTech, Inc.

This work was to evaluate Sepaths system’s performance in SPE extraction of

organophosphorus pesticide Monocrotophos in tap water, as required by a water company

of Taiwan. Tap water samples were spiked with Monocrotophos and the extractions

performed using DVB disks. The determination of the analyte was performed by HPLC.

1. Experimental



Methanol

Ethyl acetate

DVB SPE disk

HPLC-UV System

1.2 Method Summary

1) 3 x 1000 mL tap water samples

2) The water samples are spiked with 10 ppb of Monocrotophos

3) Fix the sample bottle onto the Sepaths-6 Automated SPE Module with the DVB SPE disks

4) The extracts are concentrated near to dry and made up to 1.0 ml using HPLC mobile

phase

5) Final analysis is by HPLC-UV.


pag. 21

1.3 SPE Method

Step Solvent Volume

(mL)

Soak

(min)

Soak

(sec) Cycle Collection

Dry

(min)

Dry

(sec)

Conditioning Ethyl acetate 5 2 30 1 0 0

Conditioning Methanol 5 2 30 1 0 0

Conditioning Methanol 5 0 30 1 0 0

Conditioning Water 10 0 30 1 0 0

Sample Loading 1000 0 0 1 1 0

Drying 0 0 1 3 30

Eluting Ethyl acetate 10 1 30 1 1 0 30



Table 1. SPE method by Sepaths-6 ® Automated SPE system

The method process takes 1 hour to compleatly extract No.3 samples (1 L volume).

Compared with single-channel or manual SPE systems, the efficiency of Sepaths

Automated SPE system has been greatly enhanced for the following reasons :

1) 1 to 6 samples extracted at the same time

2) No cross contamination

3) Reproducibility of the method

4) High Flow stability/accuracy thanks to Nitrogen positive pressure

2. Results

2.1 Recovery of spiked Monocrotophos in tap water samples

HPLC tr

（min）

Recovery

（%） #1

Recovery

（%） #2

Recovery

（%） #3

Average (%)

RSD (%)

7.58 88.6 90 95 91.2 3.68

Table 1. Recoveries and RSD

3. Conclusion

This study develops a method of Organophosphorus pestic extraction via Sepaths

automated SPE system coupled with HPLC-UV analysis. This method has good recovery

and the great repeatability (RSD 3.68 %). The results illustrate the reliability of this method

and the efficiency of Sepaths instrument as fast ans easy to use SPE system.


pag. 22

Determination of Polycyclic Aromatic Hydrocarbons in

Tap Water with Sepaths SPE-HPLC

LabTech, Inc.

This work was to evaluate Sepaths system’s performance in SPE extraction of Polycyclic

Aromatic Hydrocarbons (PAHs) in tap water. Tap water samples were spiked with PAHs

and the extractions performed using C18 disks. The determination of the analyte was

performed by HPLC.

1. Experimental



Methanol

n-Hexane

Methylene chloride

C18 SPE disk

HPLC-UV System

EV311 Rotary Evaporator (LabTech Ltd.)

1.2 Method Summary

1) 6 x 500 mL tap water samples

2) The water samples are spiked with 10 ppb of PAHs and mixed with 88 mL methanol

3) Fix the sample bottle onto the Sepaths-6 Automated SPE Module with the C18 SPE disks

4) The extracts are dehydrated and concentrated near to dry and made up to 2.0 ml using

HPLC mobile phase

5) Final analysis is by HPLC-UV.


pag. 23

1.3 SPE Method


2. Results

2.1 Recovery of 16 PAHs sp in tap water samples

Recovery(%) 1 2 3 4 5 6 Average RSD(%)

Naphthalene 72 81 75 78 84 70 77

83

7.0

4.6 Acenaphthylene 76 86 83 85 80 85

Acenaphthene 98 101 92 100 97 99 98 2.3

Fluorene 117 127 122 118 124 112 120 3.6

Phenanthrene 86 95 91 95 94 96 93 3.1

Anthracene 90 99 112 98 93 95 98 5.3

Fluoranthene 99 94 96 102 91 104 98 4.1

Pyrene 90 76 87 80 84 89 84 5.1

Benzo (a) anthracene 82 87 95 98 99 86 91 6.8

Chrysene 82 83 85 90 80 94 86 4.9

Benzo (b) fluoranthene 86 84 83 84 79 78 82 3.1

Benzo (k) fluoranthene 70 82 79 75 76 79 77 4.1

Benzo (a) pyrene 87 89 90 82 94 95 89 3.9

Dibenzo (a, H) anthracene 76 84 77 76 80 84 80 4.0

Benzo (GHI) Perylene 86 95 88 84 84 91 88 3.8

Indeno (123-cd) pyrene 87 78 84 86 81 83 83 3.0


Step Solvent

Volum

e

(mL)

Soak

(sec) Pressure

Dry

(sec)

Conditioning n-Hexane 10 30 10 Psi 0

Conditioning Methylene chloride 10 30 10 Psi 0

Conditioning Methanol 10 30 10 Psi 0

Conditioning DI Water 10 0 10 Psi 0

Sample Loading 500 0 6 mL/min 0

Washing 5% Methanol 10 30 10 Psi 30

Eluting Methylene chloride 8 30 10 Psi 0





pag. 24

3. Conclusion

The high recoveries and low RSDs show a reliable method to enrich very low

concentration of PAHs from water samples in a limited period with Sepaths. In this way, it

is very easy and rapid to conduct a water test project, which can be very time-consuming

with traditional method.


pag. 25

Determination of Pyrethroids in Tap Water by Sepaths

Automated SPE extraction System and HPLC

LabTech, Inc.

This work was to evaluate Sepaths system’s performance in SPE extraction of Five

Pyrethroids, including fenpropathrin, cyhalothrin, deltamethrin, fenvalerate and permethrin,

are spiked into small volume water samples and extracted by Sepaths SPE with SPE

cartridges then analyzed by HPLC to show the a rapid way to determine insecticides in

water.The determination of the analyte was performed by HPLC.

1. Experimental



Methanol

C18 SPE 500 mg 6 mL cartridge (LabTech Ltd.)

ET nitrogen concentrator (LabTech Ltd.)

HPLC-UV System

1.2 Method Summary

1) 5 x 2 mL D.I. water samples spiked with 2 ppm of 5 Pyrethroids including Fenpropathrin,

Cyhalothrin, Deltamethrin, Fenvalerate and Permethrin.

2) Run the samples on Sepaths using 500 mg 6 mL C18 SPE cartridges

3) The extracts are concentrated to 1 mL

4) Analyzed by HPLC with UV detector at 205 nm.


pag. 26

1.3 SPE Method

Step Solvent V

(mL)

Soak

(min) Cycle Dry

(min)

Conditioning Methanol 5 1 1 0

Conditioning Water 5 0 1

Sample Loading 2 0 1 0

Rinsing Water 10 0 1 10

Eluting (through sample bottle) Methanol 10 1 1 1


2. Results

2.1 Recovery of spiked Pyrethroids in water samples

No. tr

(min)

SPE-1 SPE-2 SPE-3 SPE-4 SPE-5 Average

(%)

RSD(%)

Fenpropathrin 10.170 87.1 94.0 86.1 84.5 92.3 88.8 4.61

Cyhalothrin 11.902 85.2 103.7 96.2 95.2 81.6 92.4 9.65

Deltamethrin 12.763 81.6 89.1 88.5 86.6 75.7 84.3 6.70

Fenvalerate 13.517 89.1 92.1 100.9 105.7 92.4 96.0 7.25

Permethrin 15.102 93.7 92.0 96.7 89.1 91.0 92.5 3.11


3. Conclusion

This study develops a method for Pyrethroids analysis via Sepaths automated SPE

system coupled with HPLC. The results illustrate the reliability of this method and the

efficiency of Sepaths instrument as fast and easy to use SPE system.


pag. 27

Sepaths Solid-Phase Extraction system for Determination

of Grease and Oil in Water by Gravimetric Method

LabTech, Inc.

This experiment is a preliminary test to show Sepaths’ capability to handle water samples

with high level grease and oil. Hexadecane was used as a grease standard.

1. Experimental



Carbon tetrachloride

Oil and grease SPE disk 47mm (Horizon Tech. Ltd.)

Hotplate (LabTech Ltd.)

Analytical balance

1.2 Method Summary

1) 6 x 1000 mL tap water are used for the experiment

2) 100 ppm hexadecane is spiked into 5 samples, and 1 sample is left as blank

3) Run the 6 sample using Pacific oil and grease disk

4) Evaporate the solvents from collected extracts until constant weight

5) Weighing samples

http://en.wikipedia.org/wiki/Carbon_tetrachloride


pag. 28

1.3 SPE Method

Step Solvent Volume

(mL)

Soak

(min)

Soak

(sec) Cycle Collection

Dry

(min)

Dry

(sec)

Initializing 1 30

Conditioning CCl4 10 0 30 1 0 0

Sample Loading 1000 0 0 1 1 0

Eluting (through sample bottle) CCl4 10 1 30 1 1 1 0

Eluting (through sample bottle) CCl4 10 1 30 1 1 1 0

Eluting (bypass sample bottle) CCl4 10 1 0 1 1 1 0

Eluting (bypass sample bottle) CCl4 10 1 0 1 1 4 0


2. Results

The weight of blank sample is zero, while the spiked samples’ data are listed in Table 2.

Al plate weight

(g)

Al plate and grease weight

(g)

Grease weight

(g)

Recovery

(%)

RSD

（%）

Standard 1 2.5904 2.6497 0.0593

3.5

Standard 2 2.5738 2.6325 0.0587

average 0.0590

Sample 1 2.5731 2.6366 0.0635 107.6

Sample 2 2.5684 2.6263 0.0579 98.1

Sample 3 2.5693 2.6280 0.0587 99.4

Sample 4 2.5801 2.6413 0.0612 103.4

Sample 5 2.5793 2.6363 0.0570 96.6

Average 0.05966 101.1

Table 2. Weight, recovery and RSD

3. Conclusion

Sepaths is a useful tool in determining grease and oil in water for its tightness that isolate

samples and solvents from ambient air, so that avoid the potential pollution of samples and

solvents from air-borne hydrocarbon vapor, especially for oil plant lab.

.


pag. 29

Determination of Bisphenol A in Water by Extrapid-

Rapidisk-HPLC

LabTech, Inc.

This experiment evaluate the Extrapid manual SPE equipment for extraction of Bisphenol

A from large volume water samples.

1. Experimental


Extrapid manual SPE equipment (LabTech Ltd.)

Rapidisk C18 SPE disks (LabTech Ltd.)

HPLC instrument

1.2 Method Summary

1) 3 x 300 mL tap water samples are spiked with 94 ppb Bisphenol A then add 40 mL

methanol

2) 3 x 500 mL tap water samples are spiked with 59 ppb Bisphenol A then add 40 mL

methanol

3) Run the samples on Extrapid using Rapid C18 SPE disks

4) The extracts are made up to 40.0 mL with water and analyzed by HPLC


pag. 30

1.3 SPE Method

Step Solvent Soak Dry

Conditioning Methanol 10ml 1min

Conditioning Reagent water 10ml 1min

Sample Loading

Rinsing Reagent water 10ml 30sec 1min

Eluting Methanol 10ml 1min 1min



Table 1. SPE method by Extrapid

2. Results

The recoveries and RSDs results are listed in Table 2.

Test group Recovery (%) Rsd

300ml—A 86.4

0.59% 300ml—B 85.3

300ml—C 86.5

500ml—A 83.8

0.62% 500ml—B 84.9

500ml—C 83.2

Table 2. Recovery and RSD

3. Conclusion

The use of Extrapid for the analysis of Bisphenol A in tap water shows an excellent

repeatability. However the methods is still under evaluation and higher recovery rate is

expected with future parameters optimization.


pag. 31

Determination of Phthalic Acid Esters in Water by

Extrapid-Rapidisk-HPLC

LabTech, Inc.

This experiment evaluate the Extrapid manual SPE equipment for extraction of Phthalic

Acid Esters (PAEs) from large volume water samples.

1. Experimental



Rapidisk C18 SPE disks (LabTech Ltd.)

HPLC instrument

1.2 Method Summary

1) 3 x 1000 mL tap water samples are spiked with 40 ppb of 5 PAEs species

2) Run the samples on Extrapid using Rapid C18 SPE disks

3) The extracts are made up to 40.0 mL with water and analyzed by HPLC


pag. 32

1.3 SPE Method


Conditioning Methanol 10ml 30sec

Conditioning Reagent water 10ml 30sec

Sample Loading

Rinsing Reagent water 10ml 30sec 1min

Eluting Methanol 15 ml 1min 1min

Eluting Methanol 15 ml 1min 1min


2. Results


PAEs

Recovery DMP DEP DBP DEHP DNOP

Sample 1 99.8% 97.3% 98.9% 98.4% 97.8%

Sample 2 90.0% 92.5% 91.0% 97.4% 95.7%

Sample 3 90.0% 93.7% 92.5% 94.4% 97.1%

Average 93.27% 94.5% 94.13% 96.73% 96.87%

RSD 5.7% 2.5% 4.2% 2.1% 1.1%


3. Conclusion

PAEs is a kind of highly concerned pollutant in environment and food safety. Extrapid

shows satisfying performance and analytical results in the extraction of PAEs from water

samples.


pag. 33

Extrapid SPE-HPLC for Determination of Carbamate

Pesticides in Wheat Flour

LabTech, Inc.

This experiment evaluate the Extrapid manual SPE equipment for extraction and cleanup

of Five carbamate pesticides species from wheat flour. After been extracted the samples

are concentrated by MultiVap parallel evaporator and analyzed by HPLC.

1. Experimental



Florsil SPE cartridge, 500 mg, 6mL

Graphite carbon black SPE cartridge, 500 mg, 6mL

MultiVap, parallel concentrator (LabTech Ltd.)

HPLC instrument

1.2 Method Summary

1) Weigh 5 g wheat flour into a 50 mL centrifugal tube, add 20mL acetonitrile,

homogenized for 1 min, centrifuge at 4000 r/min for 3 min

2) Take the upper solvent into another 50 mL centrifugal tube

3) Repeat the solvent extraction with 10 mL more acetonitrile and combine the extracts

4) Rinse the acetonitrile phase with 10 mL n-hexane

5) Concentrate the acetonitrile phase to near dry and make up to 2.0 mL with acetone/n-

hexane (3/7, v/v)

6) Run the samples on Extrapid using serial carbon black (upper) and florsil (lower) SPE

cartridges

7) The extracts are concentrated to near dry with MultiVap and made up to 2.0 mL with

HPLC mobile phase

8) Final analysis is by HPLC gradient


pag. 34

1.3 SPE Method


Conditioning Acetone/N-Hexane (3/7, v/v), 20 ml 30sec

Sample Loading

Rinsing Acetone/N-Hexane (3/7, v/v), 2 ml 30sec

Eluting Acetone/N-Hexane (3/7, v/v), 30ml 1min 1min


2. Results


No. tr

（min）

SPE-1 SPE-2 SPE-3 SPE-4 SPE-5 Average

(%) RSD（%）

Aldicarb 8.190 102.8 90.7 106.2 103.1 105.2 101.6 6.16

Metolcarb 9.707 82.3 85.4 87.7 89.6 86.1 86.2 3.16

Carbofuran 11.938 98.8 93.3 86.0 85.9 99.9 92.8 7.24

Carbaryl 14.597 105.0 103.4 95.1 102.4 108.1 102.8 4.68

Isoprocarb 21.712 89.5 89.4 86.7 81.4 87.1 86.8 3.79


3. Conclusion

The good results demonstrate that Extrapid is reliable platform to conduct food safety SPE

extractions.

APPLICATION NOTES - labtechsrl.com€¦ · SPE for EPA 608 for Organochlorine Pesticides and...

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