Cellulose dimethylphenylcarbamate (CDMPC)-immobilized zirconia (CDMPCZ) was used as a chiral stationary phase for enantioseparation of a set of nine racemic compounds in reversed-phase CEC. Influences of the type and composition of organic modifier and the applied voltage on enantioseparation were examined. Separation data on CDMPCZ were also compared with those on CDMPC-immobilized silica (CDMPCS). Enantiomers of the analytes investigated are well separated in ACN/phosphate buffer mobile phases. Better enantioselectivity and resolution were obtained with ACN than MeOH as the organic modifier. Retention was longer but better enantioselectivity and resolution were obtained on CDMPCZ than CDMPCS.

(S)-N-(3,5-Dinitrobenzoyl)leucine-N-phenyl-N-propylamide-bonded silica was used as a chiral stationary phase for separation of enantiomers of some racemic pi-acidic and pi-basic amino acid amides in normal phase capillary LC (CLC) and CEC. For generation of EOF in CEC, different amounts of water were added to n-hexane-isopropanol (IPA) eluents. Influences of added water and composition of polar modifier on retention, enantioselectivity and resolution were studied. Generally better separation was obtained in the eluents of lower water content. Shorter retention and better enantioselectivities were observed in the eluents of higher IPA content, whereas resolution became lower as IPA content was increased. Enantioselectivities were comparable but resolutions were much better in CEC than CLC.

Quinine (QN) is a weak anion-exchange type chiral selector and QN-based silica stationary phases have been widely used for enantioseparation of acidic chiral analytes in HPLC and recently in CEC. In this work we report enantioseparation of non-acidic chiral analytes on a quinine carbamate-immobilized zirconia (QNZ) in reversed-phase (RP) CEC. Influences of pH, composition of the buffer, acetonitrile content and the applied voltage on enantioseparation were examined. Enantiomers of the analytes investigated are well separated in acetonitrile/phosphate buffer mobile phases. Separation data on QNZ were compared to those on QN-bonded silica (QNS). Retention was longer but better enantioselectivity and resolution were obtained on QNZ than QNS.