SIMULTANEOUS ESTIMATION OF VALSARTAN AND HYDROCHLOROTHIAZIDE IN FIXED DOSE COMBINATION IN UV SPECTROPHOTOMETRY

Valsartan (VAL) and Hydrochlorothiazide (HTZ) are used in combination in treatment of Hypertension. Two simple, accurate, precise, economical and reproducible UV spectrophotometric methods have been developed for the estimation of Valsartan and Hydrochlorothiazide in Pharmaceutical formulation. Method I- Absorption ratio method (Q-analysis) using two wavelengths, 265nm (isobestic point at which both the drugs exhibit absorbance) 249nm (λ_max of Valsartan) and Method II- Area under Curve method. For the second method Area under the Curve in the range of 249 -259nm and 261-281nm was selected for the analysis of Valsartan and Hydrochlorothiazide respectively. Linearity for detector response was observed in the concentration range of 2-24mg/ml & 2-14mg/ml for Valsartan and Hydrochlorothiazide respectively. The results of analysis have been validated statistically and by recovery studies the value of standard deviation was satisfactory and recovery studies ranging from 99.54 – 99.97 % for Valsartan and 99.75 – 101.04 % for Hydrochlorothiazide were indicative of the accuracy and precision of the proposed method The proposed methods were successfully applied for the determination of Valsartan and Hydrochlorothiazide in commercial pharmaceutical preparation. All two methods were validated statistically as per ICH guidelines.