Development and validation of stability indicating RP-HPLC method for simultaneous estimation of Tolperisone HCl and Paracetamol in bulk and its pharmaceutical formulations

A new, simple, rapid, selective, precise and accurate isocratic reverse phase high performance liquid Chromatography assay method has been developed and validated for simultaneous estimation of Tolperisone and Paracetamol in tablet formulations. The separation was achieved by using C-18 column (Hypersil BDS, 150 x 4.6mm i.d.); in mobile phase pH 3.6 Phosphate Buffer +0.1% Tetra ethyl amine and acetonitrile in the ratio of 700:300 v/v. The flow rate was 1.0 mL.min-1 and the separated drugs were detected using UV detector at the wavelength of 267 nm. The retention times of Tolperisone and Paracetamol were 4.65 and 2.39 minutes respectively, indicative of rather shorter analysis time. The method was validated as per ICH guidelines. The developed method was validated for specificity, linearity, precision, accuracy, limit of detection (LOD), limit of quantification (LOQ) and robustness as per ICH guidelines. Linearity for Tolperisone and Paracetamol were found in the range of 500-1500 μg/ml and 150-450μg/ml, respectively. The percentage recoveries for Tolperisone and Paracetamol ranged from 98.6-100.7 % and 98.6-100.1%, respectively. The proposed method could be used for routine analysis of Tolperisone and Paracetamol in their combined dosage forms. The proposed method was found to be accurate, reproducible, and consistent.