High-performance liquid chromatographic determination of rufloxacin and its main active metabolite in biological fluids.

A high-performance liquid chromatographic method is described for the determination of a fluoroquinolone, rufloxacin, and its N-desmethyl metabolite in plasma, urine and bile. Samples are chromatographed on a poly(styrene-divinylbenzene) column, the eluate being monitored with a fluorescence detector. The method was validated and a detection limit of 10 ng/ml for both rufloxacin and its metabolite in all the biological matrices considered was found. The method was successfully applied in pharmacokinetic studies.