Strategies for rapid chiral analysis by capillary electrophoresis

The aim of this study was to investigate four strategies to decrease chiral CE analysis time: (1) short-end injection technique, (2) high electric field through a capillary length reduction, (3) external pressure application and (4) capillary dynamically coated to generate an important electroosmotic flow. These approaches were applied for a simultaneous enantiomeric separation of amphetamine and four related compounds using a neutral derivatised cyclodextrin (hydroxypropyl-β-cyclodextrin) as chiral selector. Analysis time and CE performances, in terms of peak efficiency and resolution, were examined. Among the investigated strategies, the dynamic coating procedure appeared to be the most suitable approach to decrease analysis time (inferior to 7 min) and improve sensitivity. Furthermore, it exhibited very good migration time repeatability (0.1%). This benefit is of utmost interest in chiral analysis for an unambiguous peak identification, especially for a complex mixture such as reported in this study.