OBJECTIVE:To determine ampicillin and cloxacillin in ampicillin sodium/cloxacillin sodium for injection simultaneously by RP-HPLC.METHODS:The determination was performed on LBondapak C18,and the mobile phase consisted of phosphate buffer(7∶ 93)at a flow rate of 1.0mL· min-1.The detection wavelength was 225nm and the column temperature was 25℃.RESULTS:The linear ranges of ampicillin and cloxacillin were 45～ 134μ g· mL-1 and 44～ 131μ g· mL-1(r=0.999 5),respectively,with recovery rates at 99.7%(RSD=0.60%)and 101.3%(RSD=0.58%),respectively.CONCLUSION:The method is simple,rapid and accurate,and suitable for the quality control of ampicillin sodium/cloxacillin sodium for injection.
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.
