Abstract A simple, rapid, and precise reversed-phase liquid chromatographic method is developed for determination of paracetamol, aceclofenac, and chlorzoxazone in their ternary mixtures of commercial pharmaceutical preparation. This method uses C18 (Phenomenex) (150mm×4.6mm), 5 μm analytical column. Mobile phase is Methanol: Disodiumhydrogen orthophosphate (ph-3, 0.05M) 65:35 v/v. The instrumental settings are at a flow rate of 1.5 ml/min; the column temperature is 20°C, and detector wavelength is 271 nm. The sample concentrations are measured on weight basis to avoid the internal standard. The method is validated and shown to be linear. The correlation coefficients for paracetamol, aceclofenac, and chlorzoxazone are 0.9993, 0.9994, and 0.999 respectively. The recovery values for paracetamol, aceclofenac, and chlorzoxazone found 98.86%, 99.67%, and 99.51%, respectively. The relative standard deviation for six replicates is always less than 2%. This HPLC method is successfully applied to the quantitative analysis of the title drugs in tablets.
Keywords RP-HPLC, Paracetamol, Chlorzoxazone, Aceclofenac.