STABILITY-INDICATING CHROMATOGRAPHIC METHODS

The present work focused on developing and validating simple precise accurate sensitive and stability-indicating chromatographic methods for the simultaneous estimation of Tolperisone Hydrochloride and Diclofenac Sodium in combined pharmaceutical dosage forms. Although RP-HPLC and HPTLC methods had been reported for their assay no stability-indicating methods were available in literature. Hence methods were developed as per ICH guidelines to ensure reliability in quality control. The optimized RP-HPLC method employed a Kromasil C18 column with methanol acetonitrile and water (80:16:4 pH 3.0) as mobile phase showing retention times of 2.93 min for Tolperisone and 4.20 min for Diclofenac. The HPTLC method used silica gel 60 F254 plates with methanol:toluene:ethyl acetate (2.5:7:0.5 v/v/v) yielding Rf values of 0.5 and 0.7 respectively. Both methods were validated for linearity precision accuracy robustness LOD and LOQ with recoveries close to 99-100%. Forced degradation under acidic alkaline oxidative thermal and photolytic conditions confirmed method specificity revealing Tolperisone to be more labile than Diclofenac.