Systematic screening approach for chiral separations of basic compounds by capillary electrophoresis with modified cyclodextrins

A simple, systematic method was developed for rapidly screening potential capillary electrophoresis (CE) separation conditions for small, amine-containing enantiomers. During method development, 39 pairs of enantiomers were investigated and partial or complete separation was achieved in every case. Baseline resolution was achieved by these initial screening conditions in over half of the cases. The screening strategy uses a bare fused silica capillary and a pH 2.5 amine-modified phosphate buffer containing one of the selected cyclodextrins (CD): dimethyl-beta-CD, hydroxypropyl-beta-CD, hydroxypropyl-alpha-CD, hydroxypropyl-gamma-CD and sulfated-beta-CD, An additional set of compounds have been screened by this approach to demonstrate the validity of the method. The paper outlines the experimental work carried out to develop the screen and describes how one might implement it for a new compound. (C) 1999 Elsevier Science B.V. All rights reserved.