A review on dispersive effects and on peak broadening in electromigration separation methods (capillary electrophoresis and electrochromatography) is presented, mainly covering papers published between the beginning of 1997 and the beginning of 2000. Most attention is drawn to work dealing with nonlinear effects that cause anomalous electromigration dispersion in electrolyte systems with two or multiple coions. Further, topics cover the comparison of electroosmotic and pressure-driven modes in electrochromatography, dispersive effects due to nonhomogeneous velocity fields in packed electrochromatography columns, to nonuniform electroosmotic flow, to sorption of analytes (mainly proteins) at the column wall or the stationary phase, and due to the influence of the nonideal column geometry like coiling or irregularities in shape.

• MeSH
• adsorpce MeSH
• chromatografie micelární elektrokinetická kapilární metody   MeSH
• chromatografie metody   MeSH
• DNA chemie   izolace a purifikace   MeSH
• elektroforéza kapilární metody   MeSH
• micely MeSH
• molekulární modely MeSH
• proteiny chemie   izolace a purifikace   MeSH
• statistické modely MeSH
• Publikační typ
• časopisecké články MeSH
• přehledy MeSH
• Názvy látek
• DNA MeSH
• micely MeSH
• proteiny MeSH

Electrophoretic focusing on an inverse electromigration dispersion (EMD) profile is based on a principle different from those of other electrophoretic separation methods. It has already proved its applicability in analytical practice by offering competitive separation performance and sensitivity and specific selectivity. It can be classified as an intermediate between field-driven and equilibrium gradient methods and is therefore interesting from the viewpoint of theory of separation methods. This work presents a comprehensive theoretical description of electrophoretic focusing on an inverse EMD profile comprising properties of the electrolyte system, formed gradients, and focused analyte zones. The separation properties are described in terms of resolution and peak capacity and their dependence on system and analyte properties is discussed from the viewpoint of how the counteracting phenomena of electromigration and dispersion are affected by electric current, voltage, and hydrodynamic and electroosmotic flow. The overall performance of the present method is shown to be comparable with other electrophoretic separation methods like zone electrophoresis or isoelectric focusing.

• Klíčová slova
• Electromigration dispersion, Electrophoresis theory, Focusing, Separation methods,
• MeSH
• elektrická vodivost MeSH
• elektroforéza kapilární metody   MeSH
• elektroosmóza MeSH
• hydrodynamika MeSH
• isoelektrická fokusace metody   MeSH
• koncentrace vodíkových iontů MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH