Abstract

A simple and precise stability indicating RP-HPLC method was developed and validated for the simultaneous determination of Olmesartan medoxomil (OLM) and Atorvastatin calcium (ATV) in Pharmaceutical dosage forms. Chromatography was carried out on Hypersil ODS C 18 (250mm x 4.6 mm, 5 particle size) column using a mobile phase of phosphate buffer (adjusted to pH 2.5 with 0.1% orthophosphoric acid): acetonitrile (30:70 % v/v) at a flow rate of 1.3 ml/min. The analyte was monitored using PDA detector at 210 nm. The retention time was found to be 3.114 min and 3.828 min. for Olmesartan medoxomil and Atorvastatin calcium respectively. The proposed method was found to be having linearity in the concentration range of 5-30 μg/ml for Olmesartan medoxomil and 2.5-15 μg/ml for Atorvastatin calcium respectively. The mean % recoveries obtained were found to be 99.97-100.06% for Olmesartan medoxomil and 99.68-100.07 % for Atorvastatin calcium respectively. Stress testing which covered acid, alkali, peroxide, photolytic and thermal degradation was performed on under test to prove the specificity of the method and the degradation was achieved. The developed method has been statistically validated according to ICH guide lines and found to be simple, precise and accurate with the prescribed values. Thus the proposed method was successfully applied for the stability indicating simultaneous estimation of Olmesartan medoxomil and Atorvastatin calcium in bulk and Pharmaceutical formulations and in routine quality control analysis.