title: Micellar electrokinetic chromatography with electroosmotic step gradient elution.
abstract: The peak capacity, defined as the maximum number of resolvable peaks, is dependent on the range of the migration-time window in micellar electrokinetic chromatography (MEKC). By applying various radial electric potential gradients across the capillary wall, the direct control of the zeta potential and the electroosmotic flow in MEKC results in a significant increase in the migration-time window and a great enhancement of the separation resolution. The enhancement in the separation resolution is obtained at a large expense in analysis time. To optimize both the separation efficiency and the resolution in MEKC, the dynamic control of electroosmosis and the migration-time window during the separations is demonstrated with the use of neutral and charged phenylthiohydantoin-amino acids (PTH-amino acids) as a model system. A simple mathematic model which is capable of predicting migration times of analytes in electroosmotic step gradient elution MEKC is presented.
authors.affiliation: Department of Chemical and Biochemical Engineering, University of Maryland, Baltimore.
authors.forename: P
authors.initials: P
authors.lastname: Tsai
authors.forename: B
authors.initials: B
authors.lastname: Patel
authors.forename: C S
authors.initials: CS
authors.lastname: Lee
mesh_terms: D000596:Amino Acids / Q000302:isolation & purification; D002845:Chromatography / Q000295:instrumentation / Q000379:methods*; D004563:Electrochemistry; D004586:Electrophoresis / Q000295:instrumentation / Q000379:methods*; D008823:Micelles; D008962:Models, Theoretical; D009995:Osmosis; D010669:Phenylthiohydantoin / Q000031:analogs & derivatives / Q000302:isolation & purification
chemical_list: D000596:Amino Acids; D008823:Micelles; D010669:Phenylthiohydantoin