Simultaneous Spectrophotometric Estimation of Hydrochlorothiazide and Bisoprolol Fumarate in Combined Dosage Forms

Rapid, precise, accurate, and specific ratiospectra derivative spectrophotometry and a simple UV spectrophotometry using simultaneous equation methods are developed for the simultaneous determination of bisoprolol fumarate and hydrochlorothiazide from combined pharmaceutical dosage forms. For ratiospectra derivative spectrophotometry, the amplitudes were measured at 202.6 nm for bisoprolol fumarate and the difference in amplitudes at 212.6 and 230 nm were measured for the determination of hydrochlorothiazide. In the simultaneous equation method, the signals were measured at 223 nm and 271.6 nm. Concentration of each drug was obtained by using the absorptivity values calculated for the drugs at two wavelengths, 223 and 271.6 nm. Commercial tablet formulations were successfully analyzed using the developed methods.