RP-HPLC METHOD DEVELOPMENT AND VALIDATION FOR THE SIMULTANEOUS ESTIMATION OF CLINDAMYCIN PHOSPHATE AND CLOTRIMAZOLE IN PHARMACEUTICAL DOSAGE FORMS Original Article M. SUDHAKAR, K. VIJAYASRI, SRIDHAR SIDDIRAJU 1 , MATURI NIRUPAMA 2, Department of Pharmaceutical Analysis and Quality Assurance * 2 ; Department of Pharmaceutical Chemistry 1 Received: 16 Aug 2014 Revised and Accepted: 15 Sep 2014 , Malla Reddy College of Pharmacy, Hyderabad, Telangana, India. Email: maturi.nirupama@gmail.com ABSTRACT Objective: The aim of this work was to develop and validate a simple Reverse Phase-High Performance Liquid Chromatography method for the simultaneous estimation of Clindamycin and Clotrimazole in pharmaceutical dosage forms. Methods: The mobile phase consists of phosphate buffer and Acetonitrile in the ratio of (48:52) with gradient programming, Hypersil BDS (250×4.6 mm,5µ) column used as stationary phase with a flow rate of 1 ml/min, injection volume 10 µl and the run time was 10 min. Detection wavelength was at 220 nm by using Photo Diode Array detector. Results: The retention times of Clindamycin and Clotrimazole were found to be 2.2 min and 5.7 min respectively. The method was validated according to ICH guidelines. Validation parameters like accuracy, precision, linearity, range, limit of detection, limit of quantification and robustness all were within the limits. The linearity responses of Clindamycin and Clotrimazole were found to be in the concentration ranges of 25-150 µg/ml and 50-300 µg/ml. The percentage recovery for both drugs was found in the range of 99-100%. The LOD & LOQ values for were found to be 1.29µg/ml and 3.93µg/ml and Clotrimazole were found to be 1.31µg/ml and 3.96 µg/ml, respectively. Conclusion: The results obtained are accurate and within the limits. Hence this method can be applicable for the estimation of Clindamycin and Clotrimazole in pharmaceutical dosage forms. Keywords: Clindamycin and Clotrimazole, RP-HPLC, Validation. INTRODUCTION Clindamycin is an antibacterial, broad-spectrum antibiotic derived from lincomycin. Clindamycin is used for the topical and systemic treatment. And it is effective as an anti-aerobic and anti-protozoal. May be useful in respiratory tract infections, and also to treat gynecological infection. Chemically Clindamycin is methyl 7-chloro-6,7,8-trideoxy-6-(1-methyl- trans-4-propyl-L-2-pyrrolidine carboxamido) 1-thio-L-threo-α-D- galacto-octopyranoside 2-(dihydrogen phosphate)[3] and the structure shown in fig. 1. Clotrimazole is an imidazole derivative with a broad spectrum of antimycotic activity. It is used for the local treatment of oropharyngeal candidiasis and vaginal yeast infections, and also used in fungal infections of the skin such as ringworm, athlete’s foot, and jock itch. Chemically Clotrimazole is 1-[(2-chlorophenyl) diphenylmethyl]-1H- imidazole[4] and the structure shown in figure-2. Fig. 1: Structure of Clindamycin phosphate The literature survey reveals that the few HPLC methods are developed and validated for the estimation of Clindamycin and Clotrimazole combination with other drugs. The reported methods available for the estimation of Clindamycin individually are new validated bio-analytical high performance liquid chromatography method[5], spectrophotometric method[6], HPLC-UV[7,8], derivative spectrophotometric method[9], RP-HPLC[10-16], liquid chromatography/electro spray ionization mass spectrometry[17], capillary electrophoresis with an end-column electro chemiluminescence[18], gas liquid chromatography[19] and ultra high performance liquid chromatography-electro spray ionization tandem mass spectrometry [20]. Fig. 2: Structure of Clotrimazole Clotrimazole has been determined in different pharmaceutical preparations by stability-indicating high performance liquid chromatography method[21], high performance thin layer chromatography[22] and spcetrophotometric method[23,24], simultaneous estimation of Clotrimazole combination with other drugs[25-27]. Since there is no reported method on simultaneous estimation of Clindamycin and Clotrimazole in combined tablet dosage forms. The main objective of this study was to develop and validate the assay method of Clindamycin and Clotrimazole in tablet dosage forms. MATERIALS AND METHODS Materials All standard purified materials were used for this study. The solvents which are used in the preparation of solutions should be HPLC grade and obtained from Merck Specialties Private Limited, International Journal of Pharmacy and Pharmaceutical Sciences ISSN- 0975-1491 Vol 7, Issue 1, 2015 Innovare Academic Sciences