HPLC and Densitometric TLC Methods for Simultaneous Determination of Pazufloxacin with Some Co-Administered Drugs in Human Plasma

Abstract

Two chromatographic methods have been developed for determination of pazufloxacin in human plasma with two co-administered drugs, cefoperazone and sulbactam sodium. First method depends on reverse phase high performance liquid chromatography. The plasma sample was extracted using mixture of ethyl acetate and 15% perchloric acid. The method was linear over the concentration range 0.5 to 20 µg/ml, 1 to 30 µg/ml and 1 to 25 µg/ ml of pazufloxacin mesylate, cefoperazone and sulbactam sodium, respectively. The mobile phase used consist of methanol, 0.01 M sodium acetate buffer (pH adjusted to 3 using trifluoroacetic acid) in a ratio 20:80 and 0.5% TEA and flow rate 1 ml/min in isocratic mode and UV-detection at wavelength 240 nm. Second method depends on densitometric thin layer chromatography. The method was linear over concentration range 1 to 20 µg/ml, 6 to 24 µg/ml and 4 to 20 µg/ml of pazufloxacin mesylate, cefoperazone and sulbactam sodium, respectively. The mobile phase used consists of chloroform, methanol and ammonia in the ratio of (11:6:2, v/v/v). Densitometric analysis was carried out at wavelength 240 nm. The stability of pazufloxacin mesylate and the coadministered drugs in plasma was confirmed during three freeze–thaw cycles (−20°C).