Simultaneous estimation and validation of losartan potassium and hydrochlorothiazide in bulk and tablet dosage form by using different spectrophotometric method

Three simple, accurate and precise spectrophotometric methods have been developed for simultaneous determination of Losartan potassium and hydrochlorothiazide in a binary mixture. In method I absorbance were measured at 235nm and 271nm corresponding to the absorbance maxima of losartan potassium and hydrochlorothiazide. Concentration of each drug was obtained by using the absorptive values calculated for both drugs at wavelengths 235nm and 271nm. Method II by dual wavelength method, losartan potassium and hydrochlorothiazide were quantified using principle that absorbance difference between two points on mixture spectra was directly proportional to concentration of component of interest and independent of interfering component. Method III describes Area Under Curve and involves measurement of area under curve in the range of 265-282nm(For LOS) and 229-242nm(For HCTZ) for the analysis in methanol. Linearity range was observed in the concentration range of 5-30μg/ml for losartan potassium and hydrochlorothiazide. Developed methods were applied to marketed formulation. The methods were validated statistically and recovery study was performed to confirm the accuracy of both methods.