title: Determination of relative enantiomer migration order using a racemic sample.
abstract: We developed a method that enables us to distinguish between the same or the opposite enantiomer migration order (EMO) of two enantiomers of a chiral compound with two different selectors. The method is applicable to racemic samples and thus a standard of the pure enantiomeric form(s) is not required. First, complexation constants and mobilities of complexes of the two enantiomers with the first and second selector are determined. However, for a racemic sample it is not possible to deduce whether the first migrating enantiomer with one selector is the same one as the first migrating enantiomer with the second selector. A specific mixture of the two selectors is designed to resolve this. In case the two enantiomers exhibit the same, respectively the opposite EMO in the two selectors, the mixture does, respectively does not separate the racemic sample. Thus two peaks are detected in the first case, while a single coalescent peak is recorded in the opposite case. We demonstrate the method on a racemic sample of amphetamine. Its relative EMO is determined with three cyclodextrins, heptakis(2,3,6-tri-O-methyl)-β-cyclodextrin, (2-hydroxypropyl)-β-cyclodextrin and heptakis(2,3-di-O-acetyl-6-O-sulfo)-β-cyclodextrin.
authors.affiliation: Charles University in Prague, Faculty of Science, Department of Physical and Macromolecular Chemistry, Prague, Czech Republic.
authors.forename: Ludmila
authors.initials: L
authors.lastname: Müllerová
authors.affiliation: Charles University in Prague, Faculty of Science, Department of Physical and Macromolecular Chemistry, Prague, Czech Republic. Electronic address: pavel.dubsky@natur.cuni.cz.
authors.forename: Pavel
authors.initials: P
authors.lastname: Dubský
authors.affiliation: Charles University in Prague, Faculty of Science, Department of Physical and Macromolecular Chemistry, Prague, Czech Republic.
authors.forename: Magda
authors.initials: M
authors.lastname: Ördögová
authors.affiliation: Charles University in Prague, Faculty of Science, Department of Physical and Macromolecular Chemistry, Prague, Czech Republic.
authors.forename: Bohuslav
authors.initials: B
authors.lastname: Gaš
mesh_terms: D000073738:2-Hydroxypropyl-beta-cyclodextrin; D000661:Amphetamine / Q000737:chemistry*; D003505:Cyclodextrins / Q000737:chemistry; D019075:Electrophoresis, Capillary / Q000379:methods; D013237:Stereoisomerism; D047392:beta-Cyclodextrins / Q000737:chemistry
chemical_list: D003505:Cyclodextrins; D047392:beta-Cyclodextrins; C486937:heptakis(2,3-di-O-acetyl-6-O-sulfo)-beta-cyclodextrin; D000073738:2-Hydroxypropyl-beta-cyclodextrin; C000609658:heptakis(2,3,6-tri-O-methyl)-beta-cyclodextrin; D000661:Amphetamine
keywords: Cyclodextrin; Dual selector system; Electromigration order; Model of electromigration; Racemate