Spectrophotometric Methods for Simultaneous Estimation of Drotaverine Hydrochloride and Aceclofenac in their Combined Tablet Dosage Form

Two simple spectrophotometric methods have been developed for simultaneous estimation of Drotaverine hydrochloride and Aceclofenac from tablet dosage form. Method I is an Absorbance correction method in which absorbance is measured at two wavelengths, 360 nm at which Aceclofenac has no absorbance and 276 nm at which both the drugs have considerable absorbance. Method II is First order derivative method which involves two zero crossing points, 249 nm (for measurement of Drotaverine hydrochloride) and 306.5 nm (for measurement of Aceclofenac). Both the methods were found linear between the range of 10-40 μg/ml for Aceclofenac and 8-32 μg/ml for Drotaverine hydrochloride. The accuracy and precision were determined and found to comply with ICH guidelines. Both the methods showed good reproducibility and recovery with % RSD in the desired range. The methods were found to be rapid, specific, precise and accurate and can be successfully applied for the routine analysis of Drotaverine hydrochloride and Aceclofenac in their combined tablet dosage form.