Choice of chiral selector for enantioseparation by capillary electrophoresis

Capillary electrophoresis (CE) is an effective tool for the resolution of enantiomers, which is accomplished by supplying the background electrolyte with a chiral selector capable of discriminating between the enantiomers concerned. A large number of chiral selectors are currently available, especially prominent among which are cyclodextrins (CDs), chiral crown ethers, chiral surfactants, ligand-exchange complexes and linear polysaccharides. The most suitable chiral selector for each specific purpose is usually selected by trial and error, which is expensive and time-consuming. This article reviews the separation capabilities of chiral selectors and provides criteria for their choice in terms of molecular size, charge, and the presence of specific functional groups or substructures in the analytes with a view to minimizing the number of trials needed. Such criteria are summarized in tabular form and their application illustrated with selected examples. (C) 2003 Published by Elsevier B.V.