托吡卡胺对映体的毛细管电泳-方波安培分离检测

采用毛细管电泳-方波安培检测法,在熔融石英毛细管(75 μm i.d.×50 cm)中,以7 mmol/L 三羟甲基氨基甲烷(Tris)-10 mmol/L柠檬酸-2 mmol/L硼酸-15mmol/L β-环糊精 （β-CD） (pH 3.0)为电泳介质,采用重力进样，高度差为20 cm,进样时间为10 s，在分离电压为15 kV,方波平衡电位+0.8 V的条件下，实现了托吡卡胺对映体的分离检测。线性范围为5~750 μmol/L,检出限为2 μmol/L。对影响分离度的因素β-CD浓度、硼酸浓度及p

Enantioseparation of Tropicamide by Capillary Electrophoresis with Square Wave Amperometric Detection

An enantioseparation method for tropicamide by high performance capillary electrophoresis with square wave amperometric detection (SWAD) was developed. The enantiomers of tropicamide were baseline separated in 16 min with an uncoated fused-silica capillary (75 microm i.d. x 50 cm) under the optimum conditions: 7 mmol/L Tris-10 mmol/L citric acid-2 mmol/L H3BO(3)-15 mmol/L beta-cyclodextrin (beta-CD) (pH 3.0) as background electrolyte, SWAD balance potential (E(b)) + 0.80 V (vs. Ag/AgCl), separation voltage 15 kV, injection height 20 cm, and injection time 10 s. The calibration curve of the enantiomers showed good linearity in the range from 5 micromol/L to 750 micromol/L with detection limit of 2 micromol/L. The average recoveries of added standards were 96% - 103%. The effects of the concentrations of beta-CD and the boric acid, the pH of the background electrolyte on resolutions (Rs) of the enantiomers were discussed in details. The proposed method was applied to the determination of a commercial tropicamide eye-drops sample without pre-treatment, and satisfactory results were obtained.