SPECTROFLUORIMETRIC METHOD FOR THE DETERMINATION OF SILODOSIN IN BULK AND PHARMACEUTICAL DOSAGE FORM

Size: px

Start display at page:

Download "SPECTROFLUORIMETRIC METHOD FOR THE DETERMINATION OF SILODOSIN IN BULK AND PHARMACEUTICAL DOSAGE FORM"

Andrea Harvey
5 years ago
Views:

Page5106 Indo American Journal of Pharmaceutical Research, 2014 ISSN NO: 2231-6876 SPECTROFLUORIMETRIC METHOD FOR THE DETERMINATION OF SILODOSIN IN BULK AND PHARMACEUTICAL DOSAGE FORM PrachiBhamre,

1 Page5106 Indo American Journal of Pharmaceutical Research, 2014 ISSN NO: SPECTROFLUORIMETRIC METHOD FOR THE DETERMINATION OF SILODOSIN IN BULK AND PHARMACEUTICAL DOSAGE FORM PrachiBhamre, Sadhana J. Rajput* Pharmaceutical Quality Assurance Laboratory, Centre of Relevance and Excellence in Novel Drug Delivery System, Shri G H Patel Pharmacy Building, Pharmacy Department, The Maharaja Sayajirao University of Baroda, Fatehgunj, Vadodara , Gujarat, INDIA. ARTICLE INFO Article history Received 14/10/2014 Available online 30/10/2014 Keywords Spectrofluorimetry, Silodosin. ABSTRACT A simple, accurate, sensitive and reproducible spectrofluorimetric method has been developed for the analysis of Silodosin in pure and pharmaceutical dosage form. Silodosin shows strong native fluorescence in methanol having excitation wavelength at 272 nm and emission wavelength at 450 nm. The calibration graph was linear in the range from 0.01 to 1µg/ml. The proposed method was statistically validated and successfully applied for analysis of capsule dosage form. The limit of detection and limit of quantification were found to be 0.003µg/ml and µg/ml respectively. The percentage recovery was found to be in the range of 98.53% ± 0.53 to 99.27% ± Corresponding author Dr.Sadhana J Rajput Prof. of Pharmaceutical Quality Assurance, Centre of Relevance and Excellence in Novel Drug Delivery System, Shri G H Patel Pharmacy Building Pharmacy Department, The Maharaja Sayajirao University of Baroda, Vadodara , Gujarat, INDIA sjrajput@gmail.com Please cite this article in press as Prachi Bhamre et al. Spectrofluorimetric Method for the Determination of Silodosin in Bulk and Pharmaceutical Dosage Form. Indo American Journal of Pharm Research.2014:4(10). Copy right 2014 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.

2 Page5107 INTRODUCTION Silodosin, chemically known as (-)-1-(3-hydroxypropyl)-5-[(2R)-2-({2-[2-(2,2,2-trifluoroethoxy)-phenoxy] ethyl} amino) propyl] -2,3-dihydro-1H-indole-7-carboxamide (figure 1),isused for the symptomatic treatment of benign prostatic hyperplasia. It acts as α 1 -adrenoceptor antagonist with high uroselectivity (selectivity for the prostate)[1]. Figure 1 Structure of Silodosin. Several methods have been described in the literaturefor the determination of Silodosinsuch as: spectrophotometry method using acetonitrile [2] and 0.1N HCl as solvent[3]; UV and HPLC method for dissolution testing [4]; RPHPLC methods[5-7]; stability indicating HPLC method [8];stability indicating UPLC method [9]; HPTLC method [10];determination of Silodosin in human plasma by LC-MS/MS method [11];LC method for determination of the enantiomeric purity of Silodosin [12] and RPHPLC method for determination of Silodosin in combination with Dutaseride [13]. The purpose of this study was to develop a fluorimetric method which is less tedious, more rapid and sensitive than the previously reported ones, for estimating Silodosin. This selective fluorimetric assay is simple and sensitive enough to be useful for determining this drug in commercialized pharmaceutical samples and can also be used for its determination in physiological fluids. EXPERIMENTAL Intrumentation All fluorescence measurements were performed on the spectrofluorimeter, RF-5301 PC (Shimadzu, Japan), with nonfluorescent glass cell of 1 cm path length. Data acquisition was performed using RFPC software version The instrument parameters are given in Table 1. Table 1 Instrument parameters. Method parameter Value Excitation Wavelength 272nm Emission Wavelength 450nm Scan Speed Fast Slit width 5 Solvent Methanol Materials and chemicals Silodosin was purchased from HangzuDayang, Co., China. AR grade methanol (Spectrochem) was used as a solvent. The formulation of Rapilif capsule (IPCA laborataries) was used for analytical application. Each capsule contains 4 mg of Silodosin. Standard and sample solutions A stock solution of Silodosin(1000μg/ml) was prepared in methanol. From this 100 μg/ml solution was prepared in methanol. Aliquots of 100μg/mlsolution were suitably diluted with methanol to give the final concentration in the range of μg/ml. The solution was scanned in the range of 200 to 700 nm against methanol as blank, to obtain the excitation and emission wavelength. The excitation and emission wavelength were found to be 272 nm and 450nm, respectively. For analysis of Silodosin in solid dosage form, a commercial brand (Rapilif, IPCA Laboratories, India), was procured from local market. Twenty capsule contents of the marketed formulation were accurately weighed. The capsule powder equivalent to 4 mg of silodosinwas weighed, transferred to 10 ml volumetric flask, dissolved in methanol and the final volume was made up to the mark. The solution was sonicated for 5 minutes and filtered through whatmann filter paper No. 40. From this solution,0.25 ml of aliquot was taken and conveniently dilutedupto 10 ml with methanol and furtheragain an aliquot of 1 ml was taken from later and diluted upto 10 ml with methanol to get the required concentration. RESULTS AND DISCUSSION The fluorescence of Silodosin was analysed in various solvents like single distillwater, 0.1M hydrochloric acid, 0.1M sodium hydroxide, methanol, ethylacetate and acetonitrile. Silodosin showed stronger native fluorescence property in methanol and 0.1M NaOH; but the sensitivity of the method was observed high in methanol as compared to 0.1M NaOH and hence methanol was selected

3 Page5108 as an optimum solvent for spectrofluorimetric analysis. The fluorescence property of the drug was studied at two excitation wavelengths i.e. 272 nm and 340 nm. At both these wavelengths the emission wavelength was found to be 450 nm. At 272 nm excitation wavelength the drug exhibited linearity in the range of µg/ml whereas at 340 nm the linearity range was µg/ml. However at 272 nm the sensitivity of the drug was comparatively better than at 340nm and hence 272 nm was selected as the excitation wavelength. Figure 1 shows the overlain spectra of Silodosin over linearity range at 450 nm emissionwavelength. Method validation The proposed method was validated as per ICH guidelines[14] for linearity, precision, accuracy, sensitivity and robustness. Linearity study was evaluated by analyzing a series of standard solutions of seven different concentrations in the range of µg/ml(y = 721.4x ; correlation coefficient R 2 = ). The overlain spectra over the linearity range are shown in figure 2. Figure 2 Overlain spectra of Silodosin in methanol. Recovery studies were done at three different levels. The pre-analyzed samples were spiked with 80%, 100% and 120% of the standard Silodosin and the mixtures were reanalyzed by the proposed method. The estimation was made in triplicate. Percentage recovery was calculated from the amount of drug found in the solution.the percentage recovery studies revealed that the recovery levels lie between 98.53% and 99.27%. Recovery results demonstrated that the proposed method was unaffected in the presence of formulation excipients and thus highly accurate as shown in Table 2. Precision was estimated by determination of the repeatability of the method. Repeatability was assessed by analyzing three different concentrations (covering the specified range of the method) in triplicate, in a day for intra-day precision and on three different days for inter-day precision. Both inter-day as well as intra-day precision showed that the relative standard deviation (% RSD)was less than 2.0 (Table 2). For LOD and LOQ determination, the calibration curve was repeated for three times and the standard deviation (SD) of the intercepts was calculated. According to ICH recommendations (1996), the approach based on the SD of the response and the slope was used for determining the limit of detection (LOD) and limit of quantitation (LOQ). The LOD and LOQ were measured as: LOD=3.3 * SD/slope of calibration curve; LOQ=10 * SD/slope of calibration curve (where, SD is standard deviation of intercepts). The theoretical values were assessed practically. The LOD and LOQ limits were found to be 0.003µg/mland µg/mlrespectively. For assessment of stability, the standard and sample solutions of Silodosinprepared in methanol, were stored at room temperature for 48hrs and at 5 C in refrigerator for upto 5 days. The solutions were found to be stable and no change in the flourescence was observed. The method was found to be specific as the results were unaffected by the presence of the excipients, which can be observed from the results of the assay of commercial formulation. The proposed spectroflourimetric method was applied to the determination of Silodosin in commercial Rapilif capsule formulation. Satisfactory results were obtained which were in good agreement with the label claim and showed 99.19±0.41% recovery (Table 2).

4 Page5109 Table 2 Summary of validation parameters and assay results. Parameters Results Calibration range(µg/ml) Detection limit (µg/ml) Quantitation limit (µg/ml) Regression equation y = 721.4x Correlation coefficient(r 2 ) Accuracy (% recovery ±SD) # Precision 80% 98.53± % 98.67± % 99.27±0.49 (%RSD)* Intraday 0.63 Interday 1.39 Assay results Label amount (mg/capsule) 4 % Recovery±SD # 99.19±0.41 # Mean value for n=3 determinations; SD=standard deviation. *Mean value for n=3 determinations at 3 levels. CONCLUSION The results indicated that this method can be used for routine quality control of silodosin in bulk and its solid dosage form. As an added benefit of spectrofluorimeter owing to the detectability and sensitivity of the drug in the nano range(i.e ng/ml), the method can also be used for bioanalytical purpose. REFERENCES 1. Yoshida M., Homma Y., Kawabe K. Silodosin.A novel selective alpha 1A-adrenoceptor selective antagonist for the treatment of benign prostatic hyperplasia. Expert OpinInvestig Drugs2007; 16 (12): Sharma C. R., Akhtar J., Jagani N. M., Shankharva Y. R., Shah J. R. UV spectrophotometric method for estimation of silodosin from its solid dosage form. Inventi Rapid: Pharm Analysis & Quality Assurance 2012;Article ID- Inventi:ppaqa/310/ Rasheed A., Mounik P., Azeem A. K., Prashanth S. S. Development and validation of silodosin in tablet formulation by various UV spectrophotometric methods. Inventi Rapid: Pharm Analysis & Quality Assurance 2012; Article ID- Inventi:ppaqa/754/ Devadasu C. H., Ravisankar P., SrinivasaBabu P., Gananadhamu S., Sowjanya S. Quantitative analysis of silodosin in capsules using uv spectrophotometry and RP-HPLC methods: application to dissolution testing. International Journal of Advances in Pharmaceutical Sciences 2013; 4(6): Runja, Chinnalalaiah,Pigili, Ravikumar. Development and validation of RP-HPLC method for estimation of silodosin in bulk and pharmaceutical dosage forms. International Journal of Pharmaceutical Sciences Review & Research 2012; 16(2): Goud V. M., Rao A. S., Ranjan S. P., Shalini S. D., Sowmya S.,Bhoga B. Method development and validation of RP- HPLC method for assay of Silodosin in pharmaceutical dosage form. International Journal of Pharma Sciences 2013; 3(2): Aneesh T. P., Rajasekaran A. Development and validation of HPLC method for the estimation of silodosin in bulk and pharmaceutical dosage form. International Journal of Biological & Pharmaceutical Research2012; 3(5): Harischandran S., Shankar Iyer R., Raju R., Shibi A., Sayana P. S. Validated stability indicating RP-HPLC method for the determination of Silodosin in pharmaceutical dosage form. International Journal for Pharmaceutical Research Scholars 2012; 1(4): Lanka A., Prasad R., Rao J. V. L. N. S., Pamidi S., Vara Prasad J., Hotha K. K. New rapid UPLC method for the estimation of impurities in the capsule dosage form of Silodosin. International Journal of Analytical and Bioanalytical Chemistry 2012; 2(4): Sayana P. S., Iyer R. S., Shibi A., Harischandran S. Development and validation of HPTLC method for quantification of Silodosin in bulk and pharmaceutical dosage form.the Pharma Innovation Journal 2012; 1(10): Zhao X., Liu Y., Xu J., Zhang D., Zhou Y., Gu J., Cui Y. Determination of Silodosin in human plasma by liquid chromatography tandem mass spectrometry. J Chromatogr B AnalytTechnol Biomed Life Sci. 2008: 877 (29): Vali S. J., Saladi S., Sait S. S., Garg L. K. Development and validation of LC method for determination of the enantiomeric purity of Silodosin in bulk drug substances. American. J. PharmTech Res. 2012; 2(5):

Page5110 13. Shah H. P., Khandar A., Deshpande S., Bagade S. Novel RP-HPLC method for simultaneous estimation of Silodosin and Dutasteride in multiunit solid dosage form.

5 Page Shah H. P., Khandar A., Deshpande S., Bagade S. Novel RP-HPLC method for simultaneous estimation of Silodosin and Dutasteride in multiunit solid dosage form. Research Journal of Pharmaceutical, Biological and Chemical Sciences. 2014; 5(2): ICH guidelines, validation of analytical procedure: Methodology Q2B; I.C.H. Harmonized Tripartite Guidelines,

MEDAK DIST. ANDHRA PRADESH STATE, INDIA. Research Article RECEIVED ON ACCEPTED ON

MEDAK DIST. ANDHRA PRADESH STATE, INDIA. Research Article RECEIVED ON ACCEPTED ON Page67 Available Online through IJPBS Volume 1 Issue 2 APRIL- JUNE 2011 SIMPLE QUANTITATIVE METHOD DEVELOPMENT AND VALIDATION OF VALSARTAN IN PUREFORM AND PHARMACEUTICAL DOSAGE FORMS BYUV SPECTROSCOPY