Evaluation of two amine-functionalized cyclodextrins as chiral selectors in capillary electrophoresis: Comparisons to vancomycin

Two different amine-functionalized beta-cyclodextrins were evaluated as chiral selectors in capillary electrophoresis. The first selector was a monosubstituted 6-ethylenediamine-derivatized beta-cyclodextrin, and the other was quaternary ammonium hydroxypropyl-beta-cyclodextrin. The former compound was more widely useful as a chiral selector and had less effect on the electroosmotic flow than the latter compound. Both tended to resolve anionic compounds. The primary attractive interaction between these host chiral selectors and their enantiomeric guests were charge-charge (ionic) and hydrophobic inclusion. Additional interactions involved hydrogen bonding and/or steric repulsions. The cationic cyclodextrins were not as widely useful in resolving anionic compounds as was vancomycin. However, they tended to be more stable and were comparatively transparent to near-UV light. (C) 1997 Academic Press.