Simple and Efficient Enantioseparation of Ofloxacin by Capillary Electrophoresis with Contactless Conductivity Detedction Using Binary Chiral Selectors / 分析化学

ABSTRACT

Novel method of enantioseparation of ofloxacin by capillary electrophoresis with capactively coupled contactless conductivity detection (C~4D) using binary chiral selectors,hydroxypropyl cyclodextrin and hydroxypropyl methyl cellulose ( HP-β-CD and HPMC) ,was developed. The enantiomers of ofloxacin were baseline separated with an uncoated fused-silica capillary(45 cm×50 m i. d. ,L_(effi) = 40 cm)under the optimum separate conditions, 20 mmol/L HAc +6 mmol/L NaAc + 12 mg/L HPMC +35 mmol/L HP-β-CD,separation voltage +13 kV,electrokinetic injection 11 kV×10 s. The calibration curve of the enantiomers showed good linearity in the range from 0. 8 mg/L to 40 mg/L with LOD =0. 3 mg/L. Effects of several factors on resolutions,such as the composition of the running buffer,the pH value,separation voltage,injection method and the parameters of C~4D detector,were investigated. The efficacy of the HP-β-CD and HPMC were discussed. The proposed method has been successfully applied to monitor the enantiomer of ofloxacin contents in the commercial Ofloacin Tablets and Levofloxacin Hydrochloride Tablets,and was demonstrated simple,rapid and reproducible.