RP-HPLC METHOD FOR SIMULTANEOUS DETERMINATION OF METRONIDAZOLE AND OFLOXACIN IN SYNTHETIC MIXTURE

Development and validation of a high-performance liquid chromatographic analytical procedure for simultaneously determining metronidazole and ofloxacin in a synthetic mixture is described in this paper. The separation was made with a LiChrosorb r RP-18 (250 x 4.6 mm) column, at 30 degrees C temperature, with isocratic mode and mobile phase, containing triethylamine, acetonitrile, and 0.3% o-phosphoric acid solution (0.02: 20: 80 v/v/v). Eluent was monitored at 290 nm and the flow rate was 1.0 ml/min. Metronidazole and ofloxacin were effectively separated with retention time (t(r)) of 3.42 min and 6.15 min, respectively, within the selected chromatographic conditions. The method was validated for analytical parameters: specificity, linearity, precision, accuracy, and limits of detection and quantitation. The calibration curves were linear in the concentration range of 12.5 to 100.0 mu g/ml for metronidazole and ofloxacin, and the regression coefficients were more than 0.999. For metronidazole and ofloxacin the recovery was 100.01% and 100.04%, respectively. This analytical procedure is applicable for the quality control of drug formulations.