Bio Analytical Method Development and Validation for Simulaneous Estimation of Nitazoxanide and Ofloxacin in Human Plasma by RP-HPLC

An isocratic Reversed-Phase High Performance Liquid Chromatography method has been developed for rapid and simultaneous separation and estimation of two antibiotics, namely, nitazoxanide and ofloxacin, in human plasma. Separation was carried out on Altima C8 (150 x 4.6 mm, 5µ) column using a mobile phase of 0.1% ortho phosphoric acid: acetonitrile (50:50, V/V) at 260 nm. The retention time of nitazoxanide and ofloxacin was noted to be 4.850 and 7.949 min, respectively. The average % recovery for nitazoxanide and ofloxacin were 98.012 % and 94.176 %, respectively and reproducibility was found to be satisfactory. The linearity was investigated in the concentration range of 0.02-2 µg/ml (r2=0.9996) for nitazoxanide and 0.008-0.8 µg/ml (r2=0.9998) for ofloxacin. The lower limits of quantification were 0.0196 µg/ml and 0.0079 µg/ml for nitazoxanide and ofloxacin, respectively, which reach the level of both drugs possibly found in human plasma. The proposed method can be applied for etermination of nitazoxanide and ofloxacin from dosage forms during pharmacokinetic study.