OBJECTIVETo establish a rapid and sensitive high-performance liquid chromatography (HPLC) method for detecting pazufloxacin concentrations in the saliva, gingival crevicular fluid and serum of healthy adults.

METHODSSamples of saliva, gingival crevicular fluid and serum were obtained from healthy adults receiving intravenous infusion of pazufloxacin. The concentrations of pazufloxacin in the samples were quantified by HPLC equipped with a reversed-phase column (Agilent Zorbax SB-C18 5 µm, 250 mm×4.6 mm). The mobile phase for pazufloxacin was a mixture of acetonitrile and 0.5% phosphoric acid containing 1% triethylamine (155:850), and 20 µl of the resulting solution was injected into the HPLC system at a flow rate of 1.0 ml/min. The detection wavelength was set at 245 nm. The samples were first deproteinized by precipitation with methanol followed by supernatant drying; the residue was reconstituted with the mobile phase and centrifuged, and the supernatants were directly injected into the HPLC system.

RESULTSPazufloxacin in the samples were totally separated without interference by any endogenous substances. The calibration curves showed a good linear regression (r>0.999). The detection limit was 10 ng/ml with within-day and between-day coefficients of variation performance all below 5% and recovery rates all above 91%.

CONCLUSIONHPLC is both sensitive and selective for quantification of pazufloxacin in saliva, gingival crevicular fluid and serum.