Simultaneous Spectrophotometric Estimation of Paroxetine Hydrochlorides and Clonazepam in Bulk and Tablet Dosage Form

Abstract

Two novel simple, accurate and precise spectrophotometric methods have been developed for quantitative estimation of Paroxetine hydrochloride and Clonazepam in the tablet dosage form. The standard stock solution was prepared by using the solvent methanol and further dilutions were carried out by using 0.1 N HCl. The method I is Vierodt’s Simultaneous method in which 291.60nm and 272.27nm was selected for estimation of Paroxetine and Clonazepam respectively, while method II is Absorbance Correction method, where 325 nm and 291nm was selected for estimation of Paroxetine hydrochloride and Clonazepam respectively. The calibration curve was plotted of the concentration range of 0.5-30μg/ml for both the drugs. Both the drugs obeyed Beer’s law in the concentration range 0.5-30μg/ml, correlation coefficient (r2<1). The precision of both the methods was found satisfactorily. The values of relative standards were not more than 2%. Both methods were validated statistically and recovery studies were carried out to confirm the accuracy. Commercial tablet formulation was successfully analyzed using the developed methods. Both these methods can be used for routine analysis for the estimation of Paroxetine hydrochloride and Clonazepam in the combined formulation. Due to the high sensitivity and simple sample preparation, the methods described can be used for undergraduate studies. Hence simple spectrophotometric methods have more advantages over sophisticated instrumental analysis such as HPLC. Hence these two simple and economical, instrumental methods always have a role in pharmaceutical analysis.