Simultaneous spectrophotometric estimation of Hydrochlorothiazide, Atenolol and Losartan potassium in tablet dosage form

Two simple, accurate and reproducible spectrophotometric methods have been developed for the simultaneous estimation of Hydrochlorothiazide (Hctz), Atenolol (Atn) and Losartan potassium (Los) in combined tablet dosage forms. The first method involves determination using the simultaneous equation method, the sampling wavelengths selected are, 272.5 nm, 224 nm and 250 nm over the concentration ranges of 0.5-30 microg/ml, 1-50 microg/ ml and 1-60 microg/ml for Hctz, Atn and Los respectively. The second method is the First order derivative method, the sampling wavelengths selected for estimation of Hctz, Atn and Los are 280.5 nm, 233 nm and 244 nm with linearity in the concentration ranges of 0.5-30 microg/ ml, 1-50 microg/ml and 1-60 microg/ml respectively. The results of the analysis were validated statistically and recovery studies were carried out as per ICH guidelines.