Abstract

A simple, sensitive, accurate stability indicating HPLC method was developed and validated for the estimation of Atorvastatin calcium and Telmisartan in bulk and pharmaceutical dosage forms. The quantification was carried out using Hypersil BDS C₁₈ (250× 4.6, 5 µm) column. The mobile phase consists of the mixed phosphate buffer of pH 6.8 and acetonitrile in the ratio of 55:45. The flow rate was found to be 1ml/min and detector wavelength was 254nm. The calibration curve was linear and the concentration range was found to be 8-48 µg/ml and 16-96 µg/ml for Atorvastatin calcium and Telmisartan with the correlation coefficient of Atorvastatin calcium and Telmisartan 0.9988 and 0.9994 respectively. The method was successfully validated in accordance to ICH guidelines. The drug undergoes degradation under acidic, alkaline, oxidation and UV conditions. For all the stability study, the formation of degradable product was confirmed by comparing to chromatogram of the solution kept under normal conditions. The Telmisartan drug was found to degrade extensively in acidic, basic, UV and mild degradation was observed when exposed to oxidation whereas Atorvastatin calcium was found to degrade extensively in acidic, basic, UV and oxidation. The proposed method can be readily utilized for bulk and pharmaceutical formulations of Atorvastatin calcium and Telmisartan.