Zero-Crossing Point Derivative Simultaneous Spectrofluorimetric Method for Quantification of Nebivolol Hydrochloride and Valsartan Combination in Tablets

A first derivative spectrofluorimetric method has been developed and validated for simultaneous quantification of Nebivolol hydrochloride (NEB) and Valsartan (VAL) in combined tablet dosage form without any prior separation of components from the sample. NEB was determined at emission wavelength of 294 nm (zero-crossing wavelength point of VAL). Similarly, VAL was measured at 404 nm (zero-crossing wavelength point of NEB). The first derivative amplitude- concentration plots were rectilinear over the range of 0.1-2.1 µg/ml; for both drugs. Analytical performance of the proposed spectrofluorimetric procedure was statistically validated with respect to linearity, range, precision, accuracy, selectivity, detection and quantification limits as per ICH guidelines. No interference was observed from common pharmaceutical additives. The % assay in commercial formulation was found to be 101.6 and 98.5 for NEB and VAL, respectively by the proposed method and % RSD values for precision and accuracy studies were found to be less than 2. The proposed method can be successfully applied for routine analysis of NEB and VAL in their pharmaceutical tablet dosage form.