IMULTANEOUS ESTIMATION OF VALSARTAN, AMLODIPINE BESYLATE AND HYDROCHLOROTHIAZIDE BY FIRST ORDER DERIVATIVE UV SPECTROPHOTOMETRIC METHOD

Simple first order derivative spectrophotometric method has been developed for simultaneousestimation of valsartan, amlodipine besylate and hydrochlorothiazide in combined dosage form. Themethod employed was multi-wavelength method for analysis using methanol: water (70:30) as a solvent.The three wavelengths 245, 265 and 279 nm were selected for estimation of valsartan, amlodipine besylate and hydrochlorothiazide respectively. Linearity was observed in the concentration range of 8-80 μg/ml, 1-10 μg/ml and 2-20 μg/ml for valsartan, amlodipine besylate and hydrochlorothiazide respectively. The recovery studies ascertained the accuracy of the proposed method and the results were validated as per ICH guidelines. The method can be employed for estimation of pharmaceutical formulations with no interference from any other excipients and diluents.