title: Chiral separations with coated and uncoated capillaries.
abstract: Chiral resolution depends on the time the two enantiomers have for active migration within the capillary. Consequently, the magnitude of the electroosmotic flow (EOF) has a paramount influence on resolution, especially for chiral acidic compounds (counterosmotic migration). In this case, when the mobility of the analytes relative to that of the EOF is known, a rule of thumb can be deduced: Coated capillaries with suppressed EOF should be used when the effective mobility of the analyte is less than 50% of that of the EOF. Uncoated capillaries give better resolution when the effective mobility of the analyte is higher than 50% of that of the EOF because of the longer effective migration distance. The efficiencies achieved are mainly a function of the time the analytes spend in the capillary when solute-wall interactions can be neglected.
authors.affiliation: Institut für Instrumentelle und Umweltanalytik, Saarbrücken, Germany.
authors.forename: M A
authors.initials: MA
authors.lastname: Cuñat-Walter
authors.forename: E
authors.initials: E
authors.lastname: Bossú
authors.forename: H
authors.initials: H
authors.lastname: Engelhardt
mesh_terms: D000596:Amino Acids / Q000737:chemistry* / Q000302:isolation & purification*; D003505:Cyclodextrins; D019075:Electrophoresis, Capillary / Q000295:instrumentation / Q000379:methods*; D007202:Indicators and Reagents; D008962:Models, Theoretical; D012822:Silicon Dioxide; D013237:Stereoisomerism
chemical_list: D000596:Amino Acids; D003505:Cyclodextrins; D007202:Indicators and Reagents; D012822:Silicon Dioxide