Development and Validation of Stability Indicating RP-HPLC Method for Combined Dosage Form of Tolperisone Hydrochloride and Diclofenac Sodium

A RP-HPLC method has been developed and subsequently validated for tablet dosage form. Here we use a mobile phase consisting methanol: acetonitrile: water (80:16:4 v/v/v) Flow rate: 0.5 ml/min (pH-3 adjusted with ortho-phosphoric acid) gave better resolution of peaks in HPLC. Kromasil C18 (150mm X 4.6mm, 5μm) column was used and detection was carried out at 275nm (PDA detector). The retention time of tolperisone hydrochloride and diclofenac sodium were found at 2.93 min and 4.2 min respectively. In which Linearity for tolperisone hydrochloride and diclofenac sodium was found to be y = 5.3727x + 4514.2, R²=0.9983, and y = 9741.8x + 48158, R²=0.9995 respectively in concentration range of 0.15–1500 μg/ml and 0.05–500 μg/ml respectively. %Assay of tolperisone hydrochloride and diclofenac sodium was found to be 99.79±0.08 w/w and 99.28±0.02. Results of all other experiments for method validation (Precision, % Recovery, specificity, LOD and LOQ, Robustness) were found within the specified criteria of ICH guideline.