Stability indicating Simultaneous estimation of Thiocolchicoside, Paracetamol and Diclofenac sodium in bulk drug and formulation by RP-HPLC

Abstract

A simple, selective, rapid, precise and economical reverse phase high-pressure liquid chromatographic method has been developed for the simultaneous estimation of Paracetamol, Thiocolchicoside and Diclofenac Sodium. The method was carried out on a Kromasil, C18 ODS (100 mm x 4.8 m, 5μ), with a mobile phase consisting of acetonitrile: Phosphat buffer adjusted pH 3 with Ortho Phoosphoric acid at flow rate of 1.0 ml/min. Detection was carried out at 228 nm. This method has been applied to formulation also and it gives expected results without interference of excipients of formulation. The linear regression analysis data for the calibration plots showed a good linear relationship over the concentration range of 100 - 500 μg/mL for Paracetamol, for Thiocolchicoside and for Diclofenac Sodium. The mean values of the correlation coefficient, slope and intercept were found to be 0.99, 80865 and 34739 for Paracetamol and 0.99, 10284 and 41683 for Thiocochicoside and 0.99, 59407, 29275 for Diclofenac Sodium respectively. The method was validated for precision, robustness and Linearity. Stability indicating method also performed for the formulation and for the mixture of Active Pharmaceutical Ingredients by using 0.1 N HCl, 0.1 N NaOH, 1% H₂O₂, % H₂O_2. Thermal degradation was performed at 105 C for 48 hr. and Photolytic degradation were also performed for 48 hrs. Validation data showed that the method is repeatable and selective for the estimation of Paracetamol, Thiocolchicoside and Diclofenac Sodium.