High-performance liquid chromatography assay for moxifloxacin: pharmacokinetics in human plasma.

A sensitive high-performance liquid chromatographic (HPLC) method for the determination of moxifloxacin in human plasma using fluorescence detection was developed. The drug and an internal standard (norfloxacin) were subjected to precolumn derivatization with 4-chloro-7-nitrobenzodioxazole (NBD-CI). The chromatographic separation was achieved by HPLC using a mixture of acetonitrile-10 mM orthophosphoric acid (pH 2.5) (80:20, v/v) as the mobile phase with isocratically system, a C18 column. The derivative is highly fluorescent at 537 nm, being excited at 464 nm. The linear and reproducible calibration curve over the range was 15-2700 ng/mL of moxifloxacin in human plasma. The limits of detection and quantitation were 6 and 15 ng/mL, respectively. This method was applied in pharmacokinetic studies moxifloxacin preparations in healthy volunteers.