SELECTIVE REVERSED PHASE HIGH PERFORMANCE LIQUID CHROMATOGRAPHY FOR THE SIMULTANEOUS DETERMINATION OF SOME PHARMACEUTICAL BINARY MIXTURES CONTAINING NSAIDS

A simple, rapid, sensitive, and economic reversed-phase High Pressure Liquid Chromatography method was developed for the simultaneous evaluation of five binary mixtures in their pharmaceutical preparations. The investigated mixtures were Ibuprofen(IP)-paracetamol(PC), Ibuprofen(IP)Chlorzoxazone( CZ), Ibuprofen(IP)-Methocarbamol(MC), Ketoprofen(KP)-Chlorzoxazone(CZ), and Diclofenac sodium(DS)-Lidocaine hydrochloride(LC). The chromatographic separation was performed using isochratic mode at a flow rate 1 mL/min, ODS C-18 column, and UV detection at 254 nm. The mobile phase consisted of acetonitrile: phosphate buffer, pH 5 (60:40). The parameters affecting separation of the investigated drugs were studied. Under the optimum assay conditions, the method gave linear calibration curves with good correlation coefficients. The limits of detection (LOD) and limits of quantitation (LOQ) ranged from 0.34-5.33 mu g/mL and 1.03-16 mu g/mL, respectively, indicating high sensitivity of the method. The assay of the investigated binary mixtures is completed in less than 5 min. The proposed method was successfully applied to the simultaneous analysis of the drugs in their pharmaceutical binary mixtures in dosage forms with good recoveries and no significant differences between proposed and reported method. This method can be routinely applied to the quality control of the investigated binary mixtures in their pharmaceutical formulations.