Two simple, precise and reproducible UV spectrophotometric methods, simultaneous equation method and Q-value analysis method, have been developed and validated for the simultaneous estimation of nebivolol hydrochloride and valsartan used as cardiovascular drugs available in capsule dosage form and nebivolol hydrochloride with hydrochlorothiazide used as antihistaminic H blocker available in tablet dosage form. The methods are based on the 1 measurement of absorbance of nebivolol hydrochloride and hydrochlorothiazide at 270.4 nm, 280.2nm and 270 nm and measurement of absorbance of nebivolol Hcl and valsartan at 246.6 nm, 280.2 nm and 275 nm respectively. These methods obeyed Beer's law in the concentration range of 0.5 - 2.5 μg /ml for nebivolol Hcl, 1.0 – 20 μg /ml for valsartan and 1.0–3.0 μg /ml for hydrochlorothiazide. The results of analysis have been validated statistically and recovery studies confirmed the accuracy of the proposed methods. These methods were successfully applied to the determination of these drugs in pharmaceutical dosage forms.
Key words : Nebivolol hydrochloride; Valsartan; Hydrochlorothiazide; Simultaneous determination; Q-Analysis method; UV Spectrophotometry.