title: Chiral capillary electrophoresis with cationic pyrrolidinium-beta-cyclodextrin derivatives as chiral selectors.
abstract: New single-isomer, cationic beta-cyclodextrins, including mono-6-deoxy-6-pyrrolidine-beta-cyclodextrin chloride (pyCDCl), mono-6-deoxy-6-(N-methyl-pyrrolidine)-beta-cyclodextrin chloride (N-CH(3)-pyCDCl), mono-6-deoxy-6-(N-(2-hydroxyethyl)-pyrrolidine)-beta-cyclodextrin chloride (N-EtOH-pyCDCl), mono-6-deoxy-6-(2-hydroxymethyl-pyrrolidine)-beta-cyclodextrin chloride (2-MeOH-pyCDCl) were synthesized and used as chiral selectors in capillary electrophoresis for the enantioseparation of carboxylic and hydroxycarboxylic acids and dansyl amino acids. The unsubstituted pyCDCl exhibited the greatest resolving ability. Most analytes were resolved over a wide range of pH from 6.0 to 9.0 with this chiral selector. In general, increasing pH led to a decrease in resolution. The effective mobilities of all the analytes were found to decrease with increasing CD concentration. The optimal concentration for most carboxylic acids and dansyl amino acid was in the range 5-7.5 mM and >15 mM for hydroxycarboxylic acids. (1)H NMR experiments provided direct evidence of inclusion in the CD cavity.
authors.affiliation: School of Chemical and Biomedical Engineering, Nanyang Technological University, Singapore.
authors.forename: Yin
authors.initials: Y
authors.lastname: Xiao
authors.forename: Yong
authors.initials: Y
authors.lastname: Wang
authors.forename: Teng-Teng
authors.initials: TT
authors.lastname: Ong
authors.forename: Liya
authors.initials: L
authors.lastname: Ge
authors.forename: Swee Ngin
authors.initials: SN
authors.lastname: Tan
authors.forename: David J
authors.initials: DJ
authors.lastname: Young
authors.forename: T T Y
authors.initials: TT
authors.lastname: Tan
authors.forename: Siu-Choon
authors.initials: SC
authors.lastname: Ng
mesh_terms: D002412:Cations; D002853:Chromatography, Liquid; D019075:Electrophoresis, Capillary / Q000379:methods*; D006863:Hydrogen-Ion Concentration; D009682:Magnetic Resonance Spectroscopy; D013058:Mass Spectrometry; D011759:Pyrrolidines / Q000737:chemistry*; D013237:Stereoisomerism; D047392:beta-Cyclodextrins / Q000737:chemistry*
chemical_list: D002412:Cations; D011759:Pyrrolidines; D047392:beta-Cyclodextrins; C031215:betadex