HIGH-PERFORMANCE LIQUID-CHROMATOGRAPHIC ASSAY AND ERYTHROCYTE PARTITIONING OF FLEROXACIN, A NEW FLUOROQUINOLONE ANTIBIOTIC

A rapid technique for sample preparation and HPLC was developed to study in vitro the erythrocyte binding and plasma protein binding of fleroxacin in the concentration range 0.2-15 μg ml-1. The red blood cell partition coefficient of fleroxacin was 1.45 ± 0.18 at 25°C and was independent of concentration, incubation time and temperature. The in vitro plasma protein binding of fleroxacin in humans, determined by two independent methods, was 47-51%. Partition studies using erythrocytes as a simple in vitro model may be useful to predict the degree of tissue uptake and the volume of distribution. © 1990.