Simultaneous spectrophotometric estimation of amlodipine and valsartan in capsule formulation

This work deals with the simultaneous determination of amlodipine besylate (AMLB) and valsartan (VAT) in a binary mixture form by two different methods. The first method of analysis is Derivative spectroscopy to eliminate spectral interference by measuring absorbance at two wavelengths 250nm and 237.5nm for AMLB and VAT respectively. The second method involves the application of Absorbance corrected for interference method at the wavelengths 250nm and 360nm. The linearity range was 10-50mcg/ml and 10-80mcg/ml for AMLB and VAT respectively. The proposed methods were successfully applied for the simultaneous determination of both drugs in commercial capsule preparation. The methods were validated statistically and recovery studies were performed to confirm the accuracy of method.