Separation and Determination of Five Fluoroquinolone Antibiotics by Ion Pair-HPLC

OBJECTIVE To establish an ion pair-HPLC with fast separation and determination of enoxacin,ciprofloxacin,fleroxacin,norfloxacin and sparfloxacin. METHODS Hypersil ODS2collumn (4.6 mm×150 mm，5 μm ) was used with 11 mmol·L-1 tetrabutylammonium bromide solution (0.5%triethylamine)-acetonitrile (96∶4) pH4.2 used by acetic acid as the mobile phase with a flow rate of 1.0 mL·min-1 and UV wavelength was set at 280 nm. RESULTS Five fluoroquinolones have been separated completely in 20 minutes.The linear range of enoxacin and norfloxacin was 4-100 g·mL-1, for ciprofloxacin and fleroxacin it was 5-90 g·mL-1，for sparfloxacin it was 8-100 μg·mL-1(r> 0.999 4).The detection limit of enoxacin and norfloxacin was 0.8 μg·mL-1,for ciprofloxacin it was 1.0 μg·mL-1, for fleroxacin it was 0.9 μg·mL-1，for sparfloxacin it was 1.2 μg·mL-1.CONCLUSION The method is simple, rapid, accurate and reproducible.