In this present paper, a novel, sensitive, UV- Spectrophotometric simultaneous equation method was proposed for the estimation of Losartan Potassium (LOS.P) and Hydrochlorothiazide (HTZ) in bulk and tablet dosage form. Water: Methanol in the ratio of 95:5 v/v was used as a solvent which exhibits maximum absorption at 215nm for LOS.P and 272nm for HTZ. Beers law was obeyed over the linear range for LOS.P is 1-20μg/ml and HTZ. The correlation coefficient (R2) was found 0.980 for LOS.P and 0.992 for HTZ respectively. The method was successfully applied for the assay of the both drugs in tablet with 99.2 % and 98.67 % purity for LOSP and HTZ respectively. The developed method was fully validated as per ICH guidelines. The percentage relative standard deviation (RSD) for accuracy was less than 2. The percentages RSD of the intra-day and inter-day variations were found also less than 2%. The limit of detection and quantification were 0.32μg/ml and 0.97 μg/ml for LOS.P and 0.09 μg/ml and 0.248 μg/ml for HTZ which indicates the sensitivity of the developed method. The present method also demonstrated robust on changing λmax and solvent volume ratio up to ± 2%. Empirical evidence from developed method concludes that it was simple, sensitive, reliable, and useful for the routine quality control analysis of LOS.P and HTZ in bulk and tablet dosage form.
