Dispersive micro-solid-phase extraction combined with online preconcentration by capillary electrophoresis for the determination of glycopyrrolate stereoisomers in rat plasma

作者：Liu, Yongjing; Yu, Lishuang; Zhang, Hua; Chen, Dawei^*

来源：Journal of Separation Science, 2018, 41(6): 1395-1404.

DOI：10.1002/jssc.201700753

• capillary electrophoresis
• cation-selective exhaustive injection
• dispersive micro-solid-phase extraction
• enantioseparation
• glycopyrrolate

A simple and sensitive analytical method for four isomers of glycopyrrolate in rat plasma was developed using cation-selective exhaustive injection-sweeping cyclodextrin-modified electrokinetic chromatography (CSEI-Sweeping-CDEKC) for online enrichment combined with dispersive micro-solid-phase extraction pretreatment. The CSEI-Sweeping-CDEKC was conducted on an uncoated fused silica capillary (40.2 cm x 75 mu m) with an applied voltage of -20 kV. The electrophoretic analysis was carried out in 30 mM phosphate solution at pH 2.0 containing 20 mg/mL sulfated-beta-cyclodextrin and 5% acetonitrile. Under these optimized conditions, the detection limit for racemic glycopyrrolate was found to be 2.0 ng/mL and this method could increase 495-fold detection sensitivity compared with the traditional injection method. Additionally, the parameters that affected the extraction efficiency of dispersive micro-solid-phase extraction were also examined systematically. The glycopyrrolate isomers in rat plasma samples as low as 0.0625 mu g/mL were able to be separated and detected by capillary electrophoresis with the aid of CSEI-sweeping. The findings of this study show that the dispersive micro-solid-phase extraction pretreatment coupled with CSEI-Sweeping-CDEKC is a rapid and convenient method for analyzing glycopyrrolate isomers in rat plasma.

• 出版日期2018-3
• 单位国家食品安全风险评估中心; 福建中医药大学