Abstract: Objective To 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. Methods Samples 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. Results Pazufloxacin 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%. Conclusion HPLC is both sensitive and selective for quantification of pazufloxacin in saliva, gingival crevicul fluid
and serum.