Simultaneous Estimation Of Etodolac And Thiocolchicoside In Their Combined Marketed Formulation By RP-HPLC

Size: px

Start display at page:

Download "Simultaneous Estimation Of Etodolac And Thiocolchicoside In Their Combined Marketed Formulation By RP-HPLC"

Elvin Lindsey
5 years ago
Views:

International Journal of PharmTech Research CODEN (USA): IJPRIF ISSN : 0974-4304 Vol.4, No.

1 International Journal of PharmTech Research CODEN (USA): IJPRIF ISSN : Vol.4, No.4, pp , Oct-Dec 2012 Simultaneous Estimation Of Etodolac And Thiocolchicoside In Their Combined Marketed Formulation By RP-HPLC Kiran Rathod*, Jitendra Patel. N.R.VekariaInstitute of Pharmacy, Junagadh, Gujarat, India. *Corres.author: krrathod11@yahoo.com Abstract: A reversed-phase-liquid chromatographic (RP -HPLC) method was developed for the simultaneous estimation of Etodolac and Thiocolchicoside in their combinedtablet dosage form. The method was carried out on a PhenomenexC-18 column (250 mm 4.60 mm i.d., particle size 5 µm), with a mobile phase consisting of methanol and phosphate buffer ph 6, (85:15 v/v) at flow rate 0.8 ml/ min. The wavelength used for detection of Etodolac and Thiocolchicoside was 259 nm. The retention time of Etodolac and Thiocolchicoside were found to be 4.39±0.10 min. and 3.52±0.10 min. respectively. The method was validated in terms of linearity, range, accuracy, precision, limit of detection (LOD) and limit of quantitation (LOQ) as per ICH guidelines. The method showed a good linearity in the concentration range of µg/ml for Etodolac and 4-24 µg/ml for Thiocolchicoside. The % recoveries of Etodolac and Thiocolchicosidewere found to be between % and % respectively.the %RSD for the method precision was found to be less than 2%.The proposed method can be successfully applied for the simultaneous estimation of Etodolac and Thiocolchicoside in combined tablet dosage form. Keywords:Etodolac, Thiocolchicoside, RP-HPLC. INTRODUCTION Etodolac chemically 2-{1,8-diethyl-1H,3H,4H,9Hpyrano[3,4-b]indol-1-yl}acetic acid has the chemical formula C 17 H 21 NO 3. Etodolac is a nonsteroidal anti-inflammatory drug (NSAID) with anti-inflammatory, analgesic and antipyretic properties. Its therapeutic effects are due to its ability to inhibit prostaglandin synthesis. It is indicated for relief of signs and symptoms of rheumatoid arthritis and osteoarthritis. Etodolac is official in the Indian Pharmacopeia 2010, in British Pharmacopeia 2009 as well as in United State Pharmacopoeia. 1-4 Thiocolchicoside, a semi-synthetic derivative of the naturally occurring compound colchicoside from the seeds of various species of Colchicum autumnale(autumn crocus, meadow saffron, Gloriosasuperba).ThiocolchicosidechemicallyN- [(7S)-3-(beta-D-glucopyranosyloxy)-1,2dimethoxy 10(methylsulfanyl)9oxo5,6,7,9tetrahydrobenzo[a] heptalen-7-yl]acetamide has the chemical formula C 27 H 33 NO 10 S. It is a muscle relaxant with antiinflammatory & analgesic properties. Thiocolchicoside binds to GABA-A and strychnine sensitive glycine receptors, acting as a GABA-A receptor antagonist.it is primarily indicated in conditions like Backache, Neuralgia, Pain, Parkinsonism, Sciatic pain.thiocolchicoside is official in the Indian pharmacopeia ,6 Figure 1. Structure of Etodolac (ETD)

2 Kiran Rathod et al /Int.J.PharmTech Res.2012,4(4) 1514 Figure 2. Structure of Thiocolchicoside (THC) Literature survey reveals that there are lots of HPLC and UV Spectroscopy methods reported for determination of Etodolac and Thiocolchicoside individually in bulk and in pharmaceutical formulation with other drugs. But no method had yet been reported forsimultaneous estimation of these two drugs using HPLC in pharmaceutical dosage forms Therefore,the present work was aimed to develop and validate a newrp- HPLC method for simultaneous estimation of Etodolac and Thiocolchicosidein pharmaceutical dosage form. EXPERIMENTAL CHEMICALS AND REAGENTS Reference standards of Etodolac and Thiocolchicosidewere procured as giftsamples from Rajesh Chemicals Ltd., Mumbai and Symed Labs. Pvt. Ltd., Ahmedabad respectively.etogesic MR tablet (400 mg Etodolac and 4 mg Thiocolchicoside ) were procured from the local market. HPLC grade Water, Methanol and AR grade Potassium dihydrogen phosphate, Potassium hydroxide were obtained from Polychem Limited, Mumbai,India. INSTRUMENTATION Separation was performed with a Shimadzu SPD- 20 A, Equipped with a Rheodyne injector valve with a 20.0 µl loop and a UV - Vis detector SPD- 20 A. The column used was PhenomenexC-18 column (250 mm 4.60 mm i.d., particle size 5 µm). Chromatographic data was obtained using Spinchrome software. CHROMATOGRAPHIC CONDITIONS The mobile phase used was consisted of Methanol : Phosphate buffer ph 6 (85:15 v/v). The mobile phase was sonicated for 15 min and filtered through a 0.2µ membrane filterpaper. Flow rate of mobile phase was 0.8 ml/min throughout the analysis. The UV visible detector was set at 259 nm. PREPARATION OF STANDARD STOCK SOLUTION 400 mg of ETD and 100 mg of THC were accurately weighed and transferred to 100 ml volumetric flasks separately and dissolved in the mobile phase to give stock solution of 4000 µg/ml and 1000 µg/ml ETD and THC respectively. The above standard stock solution were further diluted to obtain working Stock solution 160 µg/ml and 40 µg/ml ETD and THC respectively. PREPARATION OF SAMPLE SOLUTION Twenty tablets (Etogesic -MR, AlidacFortiza, Cadila Healthcare, Ahmedabad) were weighed and powdered. Powder equivalent to 400 mg of ETD and 4 mg of THC was weighed and transferred into a 100 ml of volumetric flask, dissolved in 60 ml of the mobile phase and sonicated for 20 min. and then diluted up to mark with the mobile phase. The solution was filtered using 0.2μ membrane filter paper and first few drops of filtrate were discarded (4000 μg/ml of ETD and 40 μg/ml of THC). Pipette out 10 ml of this solution into a 100 ml volumetric flask and in this flask add 9.6 ml of standard stock solution of Thiocolchicoside containing 1000 μg/ml concentration. Then make up volume with the mobile phase to get 400 μg/ml of ETD and 100 μg/ml of THC. From this solution 20 ml was taken into 50 ml volumetric flask and diluted upto mark with the mobile phase to get 160 g/ml of ETD and 40 g/ml of THC. Pipette out 2.5 ml of this solution into a 10 ml volumetric flask and diluted upto mark with the mobile phase to get 40 μg/ml of ETD and 10 μg/ml of THC. PREPARATION OF MOBILE PHASE Preparation of 0.02 M Phosphate buffer ph 6.0 Accurately weighed 2.72 gm KH2PO4 (Potassium dihydrogen phosphate) was dissolved in 1000 ml of water to and ph 6.0 was adjusted with 5% KOH solution (5 gm Potassium Hydroxide in 100ml). Preparation of mobile phase Methanol and Phosphate buffer ph 6.0 was mixed in ratio of 85:15 v/v, sonicated for 15 min. and filtered through 0.2μ membrane filter paper.

3 Kiran Rathod et al /Int.J.PharmTech Res.2012,4(4) 1515 METHOD VALIDATION SPECIFICITY: Specificity is the ability of the method to measure the analytes response in the presence of its potential impurities, excipients and diluents. Interference of impurities and excipients present in the formulationand interference of diluents in the elution of the drugs was checked. The specificity of the HPLC method was determined by comparing the chromatograms of the standard and sample solutions. LINEARITY: Linearity is studied to determine the range overwhich analyte response is a linear function ofconcentration. This study was performed by preparing standard solutions of different concentrations andanalyses were performed five times. The responses weremeasured as peak area. The calibration curves wereobtained by plotting peak area against concentration. PRECISION: The precision of an analytical method is thecloseness of replicate results obtained from analysis of thesame homogeneous sample. Precision was considered at two levels, i.e. Repeatability and Intermediate precision. Results from determination of repeatability and intermediate precision were expressed as SD and %RSD. Repeatability was studied by carrying out system precision And Method Precision. System Precision was determined from results for six replicate of synthetic mixture and Method Precision is for formulation Mixture. Intermediate precision was studied by carrying outintraday precision and Interday precision precision. Intraday precision of the developed method was evaluated by analyzing Combined working standard solutionscontaining ETD (8, 10, 12 µg/ml) and THC (32, 40, 48 µg/ml) 3 times on the same day. Each concentration was prepared in triplicate. Interday was determined by analyzing Combined working standard solutions containing ETD (8, 10, 12 µg/ml) and THC (32, 40, 48 µg/ml) on the three different days. ACCURACY: The accuracy of an analytical method is thecloseness of results obtained by that method to the truevalue for the sample. It is expressed as recovery (%),which is determined by the standard addition method.samples were spiked with thestandard containing 80, 100, and 120% concentration of sample solution and analyzed. The experiment was performed intriplicate. Recovery (%) and RSD (%) were calculated foreach concentration. LIMITS OF DETECTION AND LIMIT OF QUANTITATION: The LOD and LOQ were estimated from the set of 5 calibration curves used to determine method linearity. It may be calculated as LOD = 3.3 x (SD / Slope) LOQ = 10 x (SD / Slope) Where, SD = the standard deviation of Y- intercept of 5 calibration curves. Slope = the mean slope of the 5 calibration curves. ROBUSTNESS: The robustness study was performed to evaluate the influence of small but deliberate variation in the chromatographic condition. The robustness was checked by changing following parameters one by one. Change in the ratio of component in the mobile phase [Methanol:Buffer (83:17) &Methanol: Buffer (87:13)] Change in ph of Buffer by ± 0.2 units (ph 5.8 and ph 6.2) Change in flow rate by ± 0.2 ml/minute (0.6 ml/minute and 1.0 ml/minute) After each changes, sample solution was injected and % assay with system suitability parameters were checked. ANALYSIS OF MARKETED FORMULATION: To determine the content of ETD and THC in marketed tablet dosage form. Sample solutions were prepared and analyzed.

$2012,4(4) 1516 RESULTS AND DISCUSSION METHOD DEVELOPMENT Column chemistry, solvent selectivity (solvent type), solvent strength (volume fraction of organic solvent(s) in the mobile phase), additive$

4 Kiran Rathod et al /Int.J.PharmTech Res.2012,4(4) 1516 RESULTS AND DISCUSSION METHOD DEVELOPMENT Column chemistry, solvent selectivity (solvent type), solvent strength (volume fraction of organic solvent(s) in the mobile phase), additive strength, detection wavelength, and flow rate were varied to determine the chromatographic conditions giving the best separation. Several mobile phase compositions were tried to resolve the peaks of ETD and THC. The optimum mobile phase containing methanol and phosphate buffer ph 6 (85:15 v/v) was selected because it could resolve the peaks of ETD (RT = 4.39 ± 0.10 mi n) and THC (RT = 3.52 ± 0.10 min) with a resolution factor of Quantification was achieved with UV detection at 259 nm on the basis of peak area at 0.8 ml/min flow rate. A typical HPLC chromatogram obtained during simultaneous determination of ETD and THC is given in (Figure 3). METHOD VALIDATION LINEARITY AND RANGE: Different concentrations (16, 32, 48, 64, 80, 96 µg/ml of ETD and 4, 8, 12, 16, 20, 24 µg/ml of THC) of the mixture of twodrugswere prepared for linearity studies. The calibration curves obtained by plotting peak area against concentration showed linear relationship over a concentration range of µg/ml for ETD and 4-24 µg/ml for THC. The linear regression equations for ETD and THC were found to be y = 30.41x and y = x respectively. The regression coefficient values (r 2 ) were found to be and for ETD and THC respectively indicating a high degree of linearity. Calibration curves of ETD and THC are shown in Figure 4 and 5 respectively. Regression characteristics of the proposed HPLC method are given in Table 1. Figure 3. HPLC chromatogram obtained during simultaneous determination of ETD and THC Figure 4. Calibration curve of Etodolac Figure 5. Calibration curve of Thiocolchicoside

5 Kiran Rathod et al /Int.J.PharmTech Res.2012,4(4) 1517 Table 1. Regression characteristics of the proposed HPLC method Parameter Etodolac Thiocolchicoside Range (µg/ml) Regression coefficient (r 2 ) Slope Intercept PRECISION: The system and method precision showed a % RSD of 0.68% for ETD & 0.83% for THC and 1.22% for ETD & 1.05% for THCrespectively. The intraday precision having %RSD of ( %) of ETD and ( %) for THC. Likewise, the interday precision showed a %RSD ( %) of ETD and ( %) for THC. All data of precision are shown in Table 2. ACCURACY: Recovery studies were carried out by applying the standard addition method. It was carried out by spiking the already analyzed sample of the tablets with the standard of ETD and THC which contains concentration of 80, 100 and 120% of concentration of already analyzed sample. The average % recoveries for ETD and THC in marketed formulation were found to be between % and % for ETD and THC respectively. The results revealed that there was no interference of excipients. The results of accuracy are shown in Table 2. LIMIT OF DETECTION (LOD) AND LIMIT OF QUANTITATION (LOQ): The limit of detection and limit of quantificationwere found to be 1.04 and 3.17 µg/ml for ETD and 0.24 and 0.72 µg/ml for THC. The values indicate that the method issensitive. ROBUSTNESS The proposed method was found to be robust enough (% RSD < 2.) to w ithstand such slight changes and allow routine analysis of the sample. The result of robustness is shown in Table 2. Table 2.Summary of Validation parameters for proposed method Parameters ETD THC (1)Beer s Law Limit (µg/ml) (2) Regression equation y = 30.41x y = x (3)Correlation coefficient (r 2 ) (4) Precision System Precision (% RSD) Method Precision (% RSD) Intraday precision (% RSD) Interday precision (% RSD) (5) Accuracy (% Recovery) 80% ± ± % ± ± % ± ± 1.04 (6) LOD (µg/ml) (7) LOQ (µg/ml) (8)Robustness Change in organic phase(83:17 v/v) Change in organic phase(87:13 v/v) Change in ph (ph 5.8) Change in ph (ph 6.2) Change in flow rate(0.6 ml/minute) Change in flow rate(1.0 ml/minute)

6 Kiran Rathod et al /Int.J.PharmTech Res.2012,4(4) 1518 ANALYSIS OF MARKETED FORMULATION Analysis of marketed tablet (ETOGESIC -MR AlidacFortiza) was carried out using optimized mobile phase and HPLC conditions. The % drug content of tablets obtained by the proposed method for ETD and THC was found to be and 99.59, respectively. This showed that the estimation of dosage forms was accurate within the acceptance level of 95% to 105%. The results are given in Table 3. SYSTEM SUITABILITY PARAMETERS For system suitability parameters, seven replicateinjections of mixed standard solution were injected andparameters such as the resolution, theoretical plate and asymmetryfactor of the peaks were calculated. The results are shownin Table 4. CONCLUSION The proposed RP- HPLC method was found suitable for simultaneous estimation of Etodolac and Thiocolchicosidein their combined marketed tablet formulation. The method gave good resolution for both the drugs with a short analysis time below 5 minutes. The developed method was validated and it was found to be novel, simple, precise, accurate, and sensitive. The good % recovery in tablet forms suggests that the excipients present in the dosage forms have no interference in the determination. The %RSD was also less than 2% showing high degree of precision of the proposed method. The developed method can be used for routine analysis of Etodolac and Thiocolchicosidein combined dosage form. Table 3. Analysis of marketed Formulation Drug Label Claim Quantity Found (mg) (mg) Mean * ± SD % Amount Found Mean * ± SD Etodolac ± % ± 1.09 Thiocolchicoside ± % ± 1.26 *Average of three determination Table 4. System suitability Parameter Parameter Thiocolchicoside Etodolac Resolution Asymmetry Factor Theoretical Plates REFERENCES 1. Drug Bank Open data drug and drug target database [Internet] [updated on 2011 Apr 19] Available from: 2. Indian pharmacopoeia Ghaziabad: The Indian pharmacopoeia commission, Govt. of India Ministry of Health and Family Welfare; British Pharmacopoeia London: The department of health, The stationary office; United State Pharmacopoeia. 30thed. Rockville: USP Convention, INC; Indian pharmacopoeia Ghaziabad: The Indian pharmacopoeia commission, Govt. of India Ministry of Health and Family Welfare; Thiocolchicoside[Internet]. Available from: Thiocolchicoside 7. Balan P, Carolin NI, Parsana ML, Vanaja Rani M, Rajasekar S. Simultaneous estimation of Etodolac and Paracetamol by UV Spectrophotometric method in tablet formulation.journal of Pharmacy Research. 2011;4(6): Patel MJ, Badmanaban R, Patel CN. Reversed phase-high performance liquid chromatographic method for simultaneous estimation of tolperisone hydrochloride and etodolac in a combined fixed dose oral formulations. Pharmaceutical Methods. 2011;2(2): Bhandari A, Solanki R, Nagori BP, Nawal M, Bhandari M. UV spectrophotometric determination of Etodolac in tablet dosage form. Journal of Pharmacy Research. 2011;4(10):

7 Kiran Rathod et al /Int.J.PharmTech Res.2012,4(4) Jadia MK and Narayan UL. UV - Spectrophotometric and RP - HPLC Method Developement for Simultaneous Determination of Paracetamol and Etodolac in Pharmaceutical Dosage Form [Internet] Available from: /articles/uv-spectrophotometric-and-rp-hplcmethod-developement-for-simultaneousdetermination-of-paracetamol-and-etodolac 11. Bhavsar SM, Patel DM, Khandhar AP, Patel CN. Validated RP-HPLC method for simultaneous estimation of Lornoxicam and Thiocolchicoside in solid dosage form.j. Chem. Pharm. Res. 2010;2(2): Chitlange SS, Shinde PS, Pawbake GR, Wankhede SB. Simultaneous estimation of Thiocolchicoside and Aceclofenac in pharmaceutical dosage form by spectrophotometric and LC method. Scholars Research Library. 2010;2(2): Acharjya SK, Mallick P, Panda P, Mathrusri MA. Spectrophotometric methods for the determination of thiocolchicoside in bulk and pharmaceutical dosage forms. J Pharm Educ Res. 2010;1(1): Joshi RR and Gupta KR. Simultaneous UV- Spectrophotometric determination of Thiocolchicoside and Diclofenac in Pharmaceutical formulation. Pelagia Research Library. 2010;1(2): Goyal N, Bhandari A, Jain S, Patel R. Method development and validation of Etoricoxib and Thiocolchicoside in combined pharmaceutical solid dosage form by RP-HPLC method. International Journal of Pharmaceutical Studies and Research. 2011;2(1): Joshi RR and Gupta KR. UV- Spectrophotometric Determination of Thiocolchicoside in capsule. Scholars Research Library. 2010;2(2): Wankhede SB, Zambare SS, Chitlange SS. Estimation of ThiocolchicosideAndKetoprofen in pharmaceutical dosage form by Spectrophotometric methods. Journal of Pharmacy Research. 2010;3(4): Kumar SS, Natraj D, Khan A, Kumar BK, Rao JV. Development and Validation of RP-HPLC Method for Simultaneous Estimation of Etoricoxib and Thiocolchicoside in pharmaceutical dosage forms. International journal of research in pharmacy and chemistry2011;1(3): Wankhede SB, Zambare SS, Dixit NR, Chitlange SS. RP-HPLC Method for Simultaneous Estimation of Thiocolchicoside and Ketoprofen in Combined Dosage Form. Scholars Research Library. 2010;2(3): Dhaneshwar SR, Raut KO, BhusariVK. Validated HPLC method for simultaneous estimation of paracetamol, aceclofenac and thiocolchicoside in bulk drug and formulation. Research Journal of Pharmaceutical, Biological and Chemical Sciences. 2011;2(2): Kumar S, Joshi A, Thakur RS, Pathak AK, Shah K. simultaneous estimation of Etoricoxib and Thiocolchicoside by RP-HPLC method in combined dosage forms. ActaPoloniae Pharmaceutica n Drug Research. 2011;68 (6): *****

J Pharm Sci Bioscientific Res (4): ISSN NO

J Pharm Sci Bioscientific Res (4): ISSN NO Development and Validation of Analytical Methods for Simultaneous Estimation of Pregabalin and Amitriptyline Hydrochloride in their Combined Marketed Dosage form ABSTRACT: Nikhilkumar Patel, Gurjit Kaur,