This paper describes the validation of an isocratic HPLC method for the assay of Losartan Potassium Tablets and the evaluation of the stability of drug substance after stress test by Photodiode array detection. The HPLC separation was achieved on a liquid chromatogram is equipped with a 254 nm detector and a 4.6 ´ 25 mm column that contains 5 mm packing L1 (Hypersil BDS C18 4.6´ 250 mm, 5 mm column is suitable). A mixture of ammonium dihydrogen phosphate buffer pH 3.0 and acetonitrile (65:35) as a mobile phase, the flow rate is about 1.5 ml per minute. Chromatograph the Standard preparation, and record the peak response as directed under procedure: the tailing factor for the analyte peak is not more than 3.0 and the relative standard deviation of replicated injections is not more than 2%.
