Post on 02-Nov-2019
Pag
e26
72
Indo American Journal of Pharmaceutical Research, 2013 ISSN NO: 2231-6876
Journal home page:
http://www.iajpr.com/index.php/en/
INDO AMERICAN
JOURNAL OF
PHARMACEUTICAL
RESEARCH
Development and Validation of UV Spectrophotometric Method for Estimation of
Diclofenac Sodium and Eperisone Hydrochloride as API and in Formulated Sustained
Release Granules
Bharat Jhanwar*, Joytosh Banerjee , Atul Kumar, Badri Prakash Nagori Department of Quality Assurance, Lachoo Memorial College of Science and Tech, Pharmacy wing, Sector-A, Shastri
Nagar, Jodhpur (Raj)-342003
Corresponding author
Bharat Jhanwar Lachoo Memorial College of Science and Tech, Sector-A, Shastri Nagar, Jodhpur (Raj) – 342003.
Email: - pharmbharat@gmail.com
Copy right © 2013 This is an Open Access article distributed under the terms of the Indo American journal of Pharmaceutical
Research, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.
ARTICLE INFO ABSTRACT
Article history Received 20/03/2013
Available online
27/03/2013
Keywords Diclofenac sodium,
Dissolution studies,
Eperisone
Hydrochloride,
Formulation,
Simultaneous
estimation, Sustained
release granules.
The project, for the first time, reports the development of sustained release
granules of Diclofenac sodium and Eperisone hydrochloride. The granules were
subjected to physical tests, dissolution profiling as well as assay. The analytical
method was developed for both the drugs as API and for sustained release granules
on Shimadzu UV-1800 spectrophotometer by simultaneous equation method.
Phosphate buffer of pH 6.8 was selected as a common solvent for estimation of
Diclofenac and Eperisone at 276 nm and 261.4 nm respectively. Beer law was
obeyed in the range of 2-22 g/ml and 2.5-32.5 g/ml with correlation coefficient
of 0.999 and 0.998 respectively. Detection limit and quantification limit were
found to be 0.082 g/ml and 0.22 g/ml for Eperisone and 0.109 g/ml and
0.331 g/ml for Diclofenac respectively. Developed method was found to be
simple, accurate, precise, reproducible and in agreement with all the validation
criteria as per ICH with negligible interference from excipients. Assay results were
found to be 98.76% and 100.09% for Eperisone HCl and Diclofenac Na
respectively. The sustained release granules passed all the physical tests and
demonstrated good dissolution profile.
Please cite this article in press as Bharat Jhanwar et.al. Devlpopment and Validation of UV Spectrophotometric Method for
Estimation of Diclofenac Sodium and Eperisone Hydrochloride as API and in Formulated Sustained Release Granules. Indo American
Journal of Pharm Research.2013:3(3).
www.iajpr.com
Pag
e26
73
Vol 3, Issue 3, 2013. Bharat Jhanwar et. al. ISSN NO: 2231-6876
Introduction
Eperisone hydrochloride (Figure 1), chemically called 4-ethyl 2-methyl piperidinopropiophenone (EMPP) hydrochloride,
is an antispasmodic agent.1 It has a relatively low incidence of central depression when compared with other anti-
spasmodic drugs, which makes it widely used for the therapeutic treatment of spastic patients to relieve skeletal muscle
stiffness and back pain. It is useful in Diabetical angiopathy and thromboangitis obliterans, raynauds syndrome.2,3
Eperisone Hydrochloride is official in Japanese pharmacopoeia. Diclofenac sodium (Fig. 2) is [o-(2, 6-Dichloroanilino)
phenyl] acetic acid, which has analgesic and antipyretic properties and weak anti-inflammatory activity.4-5
Diclofenac is
official in Indian pharmacopoeia, Japanese pharmacopoeia and British pharmacopoeia. A combination of Eperisone HCl
with Diclofenac sodium as sustained release formulation has been approved by CDSCO in India in 150:100 mg
proportion. Hence, a need was felt to develop approved sustained release formulation for quantitative estimation. The
literature survey revealed that there are some analytical methods reported for Eperisone Hydrochloride and its congeners
like HPTLC, HPLC and their add-ons either individually or in combination with other drug.6-9
Many methods have been
reported in literature for determination of Diclofenac with other drugs.10-12
However, literature did not reveal any reported
methods for the simultaneous estimation of Eperisone HCl and Diclofenac sodium in combined dosage form. Hence, aim
of present work is to formulate sustained release granules of the combination, evaluate it in terms of physical properties
and dissolution profile and develop an analytical technique for estimation of the combination in formulated sustained
release granules.
Figure 1: Eperisone hydrochloride
Figure 2: Diclofenac sodium
www.iajpr.com
Pag
e26
74
Vol 3, Issue 3, 2013. Bharat Jhanwar et. al. ISSN NO: 2231-6876
Material and Methods
Equipments
Shimadzu UV-1800, connected to computer having UV- Probe software was employed with matching pair of 1 cm quartz
cuvette (Shimadzu Corporation, Kyoto, Japan). The spectral bandwidth is 0.5 nm. All weights were measured on Digital
balance GR-100 (A&D comp Ltd.).
Chemicals
Eperisone hydrochloride was kindly provided by Sun Pharma, Silvassa. Diclofenac sodium was kindly provided by
Anantha Drugs Ltd, Rajasthan. The purity of reference standards were more than 98.5%w/w. Starch, lactose, magnesium
stearate HPMC(LV-50) and talc were obtained from Loba chem. and Merck Ltd, Maharashtra. Distilled water was
obtained from in house laboratory. Chemicals and solvents used were of A.R. grade.
Preparation of buffer solution
Phosphate buffer of pH 6.8 was prepared according to I.P. 27.2 gm of potassium dihydrogen phosphate was dissolved in
1000 ml. 250 ml of this solution was transferred to a 1000 ml volumetric flask. 112 ml of 0.2M sodium hydroxide solution
was transferred. The volume was made upto 1000ml with distilled water to get a final solution of pH 6.8.
Preparation of Standard Stock Solution
Accurately weighed Eperisone and Diclofenac (50 mg) were separately transferred to 100 ml volumetric flask and
dissolved in phosphate buffer (6.8). Volumes were made up to the mark with phosphate buffer. Further 10 ml of each
resulted solution was transferred to a 100 ml volumetric flask separately and volume was made up to the mark to produce
final working standard stock solutions containing 50μg/ml of EPR and 50μg/ml DIC.
Simultaneous Equation Method
Working standard solutions having 10μg/ml of DIC and 15 μg/ml of EPR were scanned individually in range of
200-400 nm to determine there λmax. The λmax of DIC (Figure 3) and EPR (Figure 4) were found to be 261.4 nm
and 276 nm respectively.
Figure 3: Spectrum scan of Diclofenac Na (λmax276)
www.iajpr.com
Pag
e26
75
Vol 3, Issue 3, 2013. Bharat Jhanwar et. al. ISSN NO: 2231-6876
Figure 4: Spectrum scan of Eperisone HCl (λmax261.4)
Standard solutions having concentration 2.5 to 32.5 g/ml for DIC were obtained by transferring 0.5, 1.0, 1.5,
2.0, 2.5, 3.0, 3.5, 4.0, 4.5 5.0, 5.5, 6.0, 6.5 ml of standard stock solution to 10 ml volumetric flasks. Standard
solutions of EPR in the concentration range of 2 to 22 g/ml were obtained by transferring 0.4, 0.8, 1.2, 1.6,
2.0, 2.4, 2.8, 3.2, 3.6, 4.0 and 4.5 ml of the stock solution to 10 ml volumetric flasks. The volume in each
volumetric flask was made up with phosphate buffer (6.8). The absorbance of these dilutions were measured at
λmax of each other against phosphate buffer as blank and absorptivity coefficients E(1%1cm) were calculated
using Beer Lambert law for each concentration. Calibration curves were plotted at each wavelength (Figure 5-
8). Linear equations generated by calibration curves are as follows
DIC at 276.0 nm, Y = 0.03018x - 0.00042, DIC at 261.4 nm, Y = 0.02418x - 0.00217
EPR at 276.0 nm, Y = 0.02950x + 0.01543, EPR at 261.4 nm, Y = 0.04836x + 0.00305
The concentration of two drugs in mixture was calculated by using following equations.
…………..1
and
…………..2
Where, Cx and Cy are the concentrations of DIC and EPR respectively in mixture and in sample solutions. A1 and A2 are
the absorbance of sample at 276 nm (λ1) and 261.4 nm (λ2) respectively, ax1 and ax2 are the absorptivity of DIC at 276 nm
and 261.4 nm, ay1 and ay2 are the absorptivity of EPR at 276nm and 261.4nm.
Formulation of granules
The formulation of sustained release granules of diclofenac sodium and eperisone hydrochloride was prepared in the ratio
of 1:1.5. The quantities of the drug as well the excipients used are shown in table 1.
www.iajpr.com
Pag
e26
76
Vol 3, Issue 3, 2013. Bharat Jhanwar et. al. ISSN NO: 2231-6876
Table 1: Formulation of sustained release granules
S. no. Ingredients used in formula Quantity used (mg)
Batch 1 Batch 2
1 Eperisone Hydrochloride 150 150
2 Diclofenac Sodium 100 100
3 Hydroxy Propyl Methyl Cellulose (E 50-LV) 100 120
4 Starch paste (10%) Q.S. Q.S.
5 Lactose 84 65
7 Talc 11 10
8 Magnesium Stearate 4 3
Preparation of granules
Formulation of granules was done in two batches using wet granulation technique. Drug and polymer (H.P.M.C.) were
accurately weighed and sifted through sieve 40#. Binder was prepared using starch in water to generate starch paste.
Afterward cohesive mass was passed through sieve 22# and dried for 20-25 min. Dried granules were passed through
sieve 20# and mixed with other suitable excipients already sifted through sieve 60#. Dried granules with excipients were
packed in suitable air tight container for further evaluation.
Evaluation of granules
The granules were evaluated for various physical parameters like angle of repose, bulk density, tapped density, Carr’s
compressibility index, Hausner’s index and Loss on drying. Bulk density depends upon the geometry of particle and
cohesive property of it. These parameters in the prescribed limits show flow characteristics of the formulation. The results
are shown in table 2.
Table 2: Measurement of physical properties of granules
Parameters Batch-1 (Bt-1) Batch-2 (Bt-2)
Observations Mean Observations Mean
Angle of repose 19.6 20.1 19.8 19.8 21.1 21.2 21.1 21.1
Bulk Density 0.37 0.37 0.37 0.37 0.38 0.38 0.383 0.38
Tapped Density 0.45 0.44 0.45 0.45 0.48 0.46 0.478 0.48
Car’s index 18.4 17.3 17.18 17.6 20.3 20.1 19.8 20.3
Hausner’s index 1.22 1.21 1.207 1.21 1.25 1.25 1.258 1.25
L.O.D. (%Loss) 3.6 3.3
LOD: - Loss on drying
Method Validation
The developed methods have been validated in terms of linearity, range, specificity, accuracy, precision, assay, LOD and
LOQ as per ICH Q2(R1) guidelines (ICH, 2005).13
www.iajpr.com
Pag
e26
77
Vol 3, Issue 3, 2013. Bharat Jhanwar et. al. ISSN NO: 2231-6876
Linearity
Appropriate aliquots of DIC and EPR standard stock solution were transferred to volumetric flask of 10 ml capacity. The
volume was adjusted to the mark with phosphate buffer. All absorbance were measured at 276 nm and 261.4 nm.
Calibration curves were constructed by plotting average absorbance (n=6) versus concentrations for both drugs. Straight
line equations were obtained from these calibration curves. Optical and regression parameters are given in Table 3.
Range
Range of an analytical method is defined as the interval between upper and lower levels.
Table 3: Optical and regression characteristics
Parameters Eperisone HCl Diclofenac sodium
261.4 nm 276 nm 276 nm 261.4 nm
Beer’s law limit 2.0-22.0 2.0-22.0 2.5-32.5 2.5-32.5
Absorptivity coefficients 48.40 31.45 31.17 24.02
Molar absorptivity 14.3 x 103 9.3 x 10
3 9.9 x 10
3 7.6 x 10
3
Sandell’s sensitivity 0.02066 0.03179 0.03208 0.04163
Slope (m)
Intercept (c)
0.04836 0.02950 0.03018 0.02418
+0.00305 +0.01543 -0.00042 -0.00217
Correlation coefficient (r2)
0.9996 0.9985 0.9989 0.9993
Table 4: Value of different type of range
S. No Range Diclofenac Na Eperisone HCl
1 Linearity 2.5-32.5µg/ml 2.0-22.0 µg/ml
2 Working 0.331-32.5 µg/ml 0.2476- 22.0 µg/ml
3 Target concentration 17.5 12.0
4 Target range 14.0, 17.5, 21.0 9.6, 12.0, 14.4
Working range: It begins from limit of quantitation to the maximum concentration used for the development of the
analytical method.
Linearity range: It is the interval in which the response is directly proportional to the concentration between the
upper and lower levels.
Target concentration: It is defined as the concentration, which is equal to the midpoint of linearity range.
Target range: It is that concentration which is 80%, 100% and 120% of the target concentration.
The various ranges have been reported in table 4.
Specificity
Commonly used excipients (lactose, starch, magnesium stearate and talc) were added into a pre-weighed quantity of
standard drug synthetic mixture (1:1.5) and then absorbance was measured before and after addition of excipients.
www.iajpr.com
Pag
e26
78
Vol 3, Issue 3, 2013. Bharat Jhanwar et. al. ISSN NO: 2231-6876
Calculations were done to determine the quantity of the drugs and the interference of additives on absorbance as shown in
table 5.
Accuracy
Accuracy was determined from recovery of the method by spiking of standard drug mixture of DIC and EPR (1:1.5) to the
pre-analyzed granules mixture (12:8) preparation at 3 different concentration levels 20%, 40% and 60% of ratio of drug in
formulated granules. Spiking above that level produced absorbance beyond the beer lamberts range. Each concentration
was analyzed 9 times and average recoveries are shown in table 6.
Table 5: Specificity study for the synthetic mixture
S.No. Diclofenac sodium : Eperisone HCl % Interference
Diclofenac Na (276nm) Eperisone HCl (261.4nm)
1. 2.5:3.75 0.3846 0.806
2. 5.0:7.5 -0.196 0.132
3. 7.5:11.25 0.119 0.1776
4. 10.0:15 0.2979 0.465
5. 12.5:18.75 0.080 0.2668
6. 15.0:22.5 0.1980 0.2665
7. 17.5:26.25 0.1141 0.1888
Mean 0.142 0.145
Table 6: Data for accuracy or recovery studies
Preanalyzed granules mixture
EPR:DIC=12 : 8
Spiking concentration
EPR:DIC=1.5:1
Mean percent
recovery
%RSD
or %CV
Eperisone HCl (EPR) 2.5, 5.0 and 7.5 99.44 0.361 0.363
Diclofenac sodium (DIC) 1.68, 3.3 and 5.0 99.91 0.433 0.434
EPR: - Eperisone, DIC: - Diclofenac
Precision in mixture
Repeatability
It indicates the precision under the same operating conditions over a short interval of time and inter-assay
precision. Repeatability was performed for six times with single concentration ratio (12:8) in formulated
granules (EPR: DIC).
Intermediate Precision: In intra-day study concentration of drugs were calculated on the same day at an
interval of two hour. In inter day study the drug contents were calculated on three different days at 80%, 100%
and 120% of ratio (12:8) in formulated granules. The results of statistical analysis as are given in table 7.
www.iajpr.com
Pag
e26
79
Vol 3, Issue 3, 2013. Bharat Jhanwar et. al. ISSN NO: 2231-6876
Limit of Detection and Quantitation
LOD and LOQ were determined from the linearity data. This helps to determine sensitivity of the method.
Assay
About 450 mg of formulated granules were weighed (unit batch) and were finely triturated. Proper dilutions were done up
to 8 g/ml and 12 g/ml of DIC and EPR respectively and absorbance were measured (n=6). Percent weight claim of
formulated sustained release granules of DIC and EPR was determined by using equation 1 and 2. The results are given in
table 8.
Figure 5: Standard curve of Eperisone HCl at 261.4 nm.
Figure 6: Standard curve of Eperisone HCl at 276nm
Figure 7: Standard curve of Diclofenac at 276 nm
www.iajpr.com
Pag
e26
80
Vol 3, Issue 3, 2013. Bharat Jhanwar et. al. ISSN NO: 2231-6876
Figure 8: Standard curve of Diclofenac sodium at 261.4nm
Table 7: Precision studies values and results
Concentration levels
in ratio 1.5:1
Repeatability (12:8) Reproducibility
EPR 12 g/ml DIC
8 g/ml
Intra-day Inter-day
EPR DIC EPR DIC
9.6 : 6.4
(80%)
---------- ----------- 9.6
0.115
6.5
0.022
9.6
0.047
6.48
0.032
12 : 8
(100%)
12.06
0.047
8.04
0.0340
12.07
0.113
8.02
0.109
12.07
0.081
8.06
0.035
14.4 : 9.6
(120%)
---------- ----------- 14.4
0.026
9.67
0.041
14.42
0.054
9.58
0.042
Mean % RSD 0.3897 0.4228 0.71 1.05 0.513 0.461
EPR: - Eperisone, DIC: - Diclofenac, RSD: - Relative standard deviation
Table 8: Result of assay using developed method
Approved
formulation &
ratio (S.R.)
Actual Claim
weight (mg) in
prepared formula
Mean Concentration
found
( g/ml) *
Mean Amt. found per
450 (mg) *
Percent amount
found per 450 mg
(Assay)
EPR 150 153.6 12.05 151.7 98.76
DIC 100 102.4 8.02 102.5 100.09
* Average of six determination, SR: - Sustained release, mg: - milligrams
www.iajpr.com
Pag
e26
81
Vol 3, Issue 3, 2013. Bharat Jhanwar et. al. ISSN NO: 2231-6876
In Vitro Release (Dissolution studies)
In vitro release was determined by using USP-II single paddle type apparatus. It was operated at 50 rpm in 1000 ml of
phosphate buffer (6.8) for 9 hours at 37 0.5◦C. The results are shown in table 9. Higuchi curve, Korsemeyer peppas curve
and First order release curve were used to represent the dissolution profile as shown in figure 9 to 14.
Figure 9: Higuchi curve for Diclofenac sodium
Figure 10: Higuchi curve for Eperisone hydrochloride
Figure 11:Korsmeyer Peppas curve for Eperisone hydrochloride
www.iajpr.com
Pag
e26
82
Vol 3, Issue 3, 2013. Bharat Jhanwar et. al. ISSN NO: 2231-6876
Figure 12: Korsmeyer Peppas curve for Diclofenac sodium
Figure 13: First order release curve for Diclofenac sodium
Figure 14: First order release curve for Eperisone HCl
Results and discussions
Linearity: Beer law was obeyed in the range of 2-22 g/ml and 2.5-32.5 g/ml respectively for Eperisone
hydrochloride and Diclofenac sodium at 261.4 and 276.0 nm with coefficient of correlation 0.999 and 0.998, 0.999 and
0.998 respectively. The data are shown in table 3.
www.iajpr.com
Pag
e26
83
Vol 3, Issue 3, 2013. Bharat Jhanwar et. al. ISSN NO: 2231-6876
Specificity
Developed method has negligible excipients interference of less than 0.5%. The data are shown in table 5.
Accuracy
Accuracy was determined using recovery studies on formulated sustained release formulation. Recovery was found to be
greater than 98% which showed good accuracy of method for estimation as show in table 6.
Precision
Precision was determined by studying the repeatability and intermediate precision. Results indicate good repeatability and
intermediate precision. Percentage RSD was found to be less than 2 as shown in table 7.
Sensitivity
The LOD values were found to be 0.0820 g/ml and 0.1092 g/ml. LOQ values were found to be 0.220 g/ml and 0.331
g/ml for EPR and DIC respectively. Low values of LOD and LOQ indicated good sensitivity of proposed methods.
Assay
Percentage assay of the drugs in formulated sustained release granules was found to be 98.76% and 100.09% for EPR and
DIC with standard deviation less than 2 respectively. The data are shown in table 8.
Dissolution studies
Batch I showed 98% release whereas batch II showed more sustained release of 95% after 9 hours that could be extended
up to 10 hours. Data of In-vitro dissolution profiling are given in table 9-10. Korsmeyer Peppas kinetic model was found
to exhibit good correlation coefficient of 0.99 for both drugs.
Table 9: - Dissolution profile of drug from sustained release granules
Percent drug dissolved/1000ml of phosphate buffer (6.8)
Time in
hours
Batch I Batch II
Diclofenac Na Eperisone HCl Diclofenac Na Eperisone HCl
1 24.6 22.6 23.2 21.5
2 41.1 33.8 32.5 28.7
3 56.4 51.6 42.7 38.3
4 69.2 60.2 51.7 45.7
5 77.1 76 61.7 54.3
6 84.6 82.1 71.6 67.9
7 93.6 88 83.6 73.8
8 96.7 94 87.2 81.8
9 98.4 98 95.1 91
HCl: - Hydrochloride, Na: - Sodium
Table 10: Correlation coefficients of kinetic models
www.iajpr.com
Pag
e26
84
Vol 3, Issue 3, 2013. Bharat Jhanwar et. al. ISSN NO: 2231-6876
Kinetic Models Correlation Coefficient (r2 )
Batch –I (100 mg HPMC) Batch –II (120 mg HPMC)
DIC EPR DIC EPR
First order 0.952 0.93 0.904 0.914
Higuchi Square root 0.97 0.96 0.974 0.985
Korsmeyer Peppas 0.98 0.988 0.991 0.997
HPMC:- hydroxy propyl methyl cellulose and EPR: - Eperisone, DIC: - Diclofenac
Conclusion
Sustained release granules of Eperisone HCl and Diclofenac Na were successfully formulated and evaluated for physical
properties and dissolution profile. A simple and economic U.V. spectrophotometric method has also been successfully
developed estimation the same and was found to be specific, accurate and precise as well as having good reproducibility.
It followed all the parameters for validation as per ICH (Q2R1) guidelines. Hence, the developed method can be used as
routine analysis of any marketed sustained release dosage form of the given combination.
Acknowledgments
The authors are to M/s Sun Pharmaceuticals Ltd, Silvassa (Dadar) and M/s Anantha Drugs Ltd, Ganganagar (Raj.) for
standard drugs. The author is highly grateful to Prof (Dr) Javed Akhtar (Department of QA, JNU, Rajasthan), for his
constant guidance and support. The author would also like to thank Mr. Sourabh Jain and Mr. Shekhar Choudhary for
estending their support in the completion of the project.
References
1. Japanese Pharmacopoeia. 15th ed. The Ministry of Health, Labour and Welfare, Tokyo: Prefectural Office; 2007.
p. 618, 1706.
2. Cabitza P, Randelli P. Safety and efficacy of Eperisone in patients with low back pain a double blind randomised
study. European Review for Medical and Pharmacological Sciences 2008; 12: 229-235.
3. Fujioka M, Kuriyama H. Eperisone an antispasmodic drug posse’s vasodilation action on guinea pig basilar
artery. Journal of Pharmacology Experiments Therapeutics 1985; 235(3): 757-63.
4. Indian Pharmacopoeia. Volume-I, Electronic edition, Government of India, Ministry of Health and Welfare,
Ghaziabad: Indian Pharmacopoeia commission; 2007. p. 115
5. Tripathi K D. Essential Medical Pharmacology. New Delhi: Jaypee Brothers; 2008. p. 183, 193, 194.
6. U.S. Pharmacopeia 34, National Formulary 29, General Chapter <1225>, Validation of compendial procedures,
Vol. 1, Rockville, MD: United States Pharmacopeial Convention; 2011. p. 778
7. Liawruangrath S, Liawruangrath B. High performance thin layer chromatographic determination of tolperisoneh
hydrochloride. Journal of Pharmaceutical and Biomedical Analysis 1999; 20: 401-404.
8. Ding L, Wang X, Yang Z, Chan Y. The use of HPLC/MS, GC/MS, UV AND IR to identify a degradation product
of eperisone hydrochloride in the tablets. Journal of Pharmaceutical and Biomedical Analysis 2008; 46(2): 282-
87.
www.iajpr.com
Pag
e26
85
Vol 3, Issue 3, 2013. Bharat Jhanwar et. al. ISSN NO: 2231-6876
9. Mand P, Kadikar H. Method Development and Statistical Validation of UV Spectrophotometric Method for
Estimation of Tolperisone hydrochloride and Paracetamol in Synthetic Mixture and Combined Dosage Form.
International Journal of Pharmaceutical Research and Bio-Science 2012; 1(1): 256-275.
10. Kannan K, Rajarajan R. Dosage Form Design and Evaluation of Eperisone hydrochloride Matrix Film Coated
Extended Release Tablets. International Journal of Pharmacy and Pharmaceutical Sciences 2012; 4(2): 575-581.
11. Mohammed A, Sharma S. Separation of co-existing Paracetamol and Diclofenac sodium on silica gel ‘H’ layers
using surfactant mediated mobile phase: Identification of Diclofenac sodium form human urine. Farmacia 2009;
57: 201-211.
12. Lohe RW, Suruse PB. Spectrophotometric methods for simultaneous estimation of Rabeprazole and
Diclofenac from Combined Tablet Dosage Form. Asian Journal of Research Chemistry2008; 1:26-28.
13. Radhakrishnan V, Habibuddin M. Dissolution Profiling of Bilayered Conventional Release Paracetamol
and Sustained release Diclofenac sodium (by Simultaneous Estimation Method UV). International
Journal of Pharmacy and Pharmaceutical Sciences 2011; 3(03):186-190.
14. International Conference on Harmonization (ICH) (2005, Nov.), Harmonized tripartite guideline Q2
(R1), Validation of analytical procedures: Text and methodology.
BJRJL78451001254
Submit your next manuscript to IAJPR and take advantage of: • Access Online first • Double blind peer review policy • No space constraints • Rapid publication • International recognition Submit your manuscript at: editorinchief@iajpr.com