Development and validation of high-performance liquid chromatographic method for determination of ofloxacin and lomefloxacin in human plasma

A high-performance liquid chromatographic method for the determination of ofloxacin and lomefloxacin in human plasma has been developed and validated. The effect of organic modifiers on the retention of the investigated drugs was investigated. A simple isocratic chromatographic assay with UV-detection at 280 nm was performed on a Hibar Lichrospher 100 RP 8 column (250 x 4.6 mm, 5 μm. Merck, Germany) using a mixture of acetonitrile and 0.5 % triethylamine in water (pH adjusted to 2.5 with H 3 PO 4 ) (15:85, V/V) as the mobile phase at flow rate of 1.2 mL min - 1 . The calibration curves were linear in the concentration ragne of 0.5 - 6.0 μg mL - 1 for ofloxacin and 0.2-4.5 pg mL - 1 for lomefloxacin.