UV DERIVATIVE SPECTROPHOTOMETRIC ASSAY OF NICARDIPINE AND ITS PHOTODEGRADATION PRODUCT

A fourth-order derivative spectrophotometric method was developed for a direct and simultaneous determination of nicardipine and its pyridin e photodegradation product, which also represents its main metabolite, in bulk and in pharmaceutics. The analyte concentrations were correla ted with spectral measurements through equations obtained by simple an d multiple regression analysis. The recovery values from synthetic mix tures were verified to be from 95 to 101% and the precision, expressed as RSD, under 3%. The determination and quantification limits of the photoproduct were found to be 0.2 and 0.8%, respectively. This method is suitable for uniformity content analysis in pharmaceutical preparat ions and stability tests in routine control.