ENANTIOMERIC SEPARATION OF ACIDIC DRUGS BY CAPILLARY ELECTROPHORESIS USING A COMBINATION OF CHARGED AND UNCHARGED BETA-CYCLODEXTRINS AS CHIRAL SELECTORS

High resolution could be achieved for the enantiomers of acidic drugs, namely, sulindac, fenoprofen, ketoprofen, warfarin, and hexobarbital, in a buffer of pH 3 by the simultaneous addition of uncharged and cha rged beta-cyclodextrin derivatives. The interaction of the analytes wi th the anionic sulfobutyl ether beta-cyclodextrin provides the analyte s with an adequate electrophoretic mobility whereas the interaction wi th various neutral beta-cyclodextrins generates high enantioselectivit y, Five neutral cyclodextrins, the native beta-cyclodextrin, as well a s methyl-, dimethyl-, trimethyl- and hydroxypropyl-beta-cyclodextrin, were tested to enhance the enantioselectivity of the electrophoretic s ystem, High resolution values and the shortest analysis times for the five drugs tested were achieved in a buffer made of 100 mM phosphoric acid adjusted to pH 3 with triethanolamine and containing dimethyl- or trimethyl-beta-cyclodextrin in addition to sulfobutyl ether beta-cycl odextrin.