Capillary Electrophoresis - Beck, Wolfgang

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Résumé :
Capillary electrophoresis (CE), also designated by the acronym HPCE for High Per? formance Capillary Electrophoresis is a rapidly growing analytical separation method. It unites the separation technique of classical electrophoresis on plates with the instrumental methods of chromatography with respect to direct detection of the solutes separated in the capillary and their ready identification and quantification. The initial problems of inadequate reproducibility in quantitative analysis, due to the necessity of handling extremely small volumes, have largely been solved in the sec? ond generation commercial instruments. Hence, a rapid and reliable separation sys? tem is available for ionic compounds from the smallest cation (the lithium ion) up to poly anions with molecular weights ranging in the millions (such as DNA molecules). The methods of gel electrophoresis and isoelectric focusing can be readily extended to separation techniques carried out in a capillary. For nonionic compounds an addi? tional separation method is available in the form of micellar electrokinetic chroma? tography (MEKC). This involves a true chromatographic separation process because the distribution of the analytes between the buffer and the micelles is superimposed on the electrophoretic migration, which contributes substantially to the selectivity.

Sommaire:
1 Introduction.- 2 Principles of Capillary Electrophoresis.- 3 Theoretical Foundations and Their Influence on the Analytical Results.- 3.1 Electrophoretic Migration.- 3.2 Conductivity.- 3.3 Electroosmotic Flow.- 3.4 Band Broadening.- 4 Instrumentation.- 4.1 Power Supply.- 4.2 Capillaries.- 4.3 Sample Introduction.- 4.4 Thermostating.- 4.5 Detection.- 4.6 Special Problems of Quantitative Analysis in CE.- 5 Capillary Zone Electrophoresis (CZE).- 5.1 Principles of Optimization in CZE.- 5.2 Indirect Detection Methods in CE.- 5.3 Capillary Zone Electrophoresis of Proteins.- 6 Micellar Electrokinetic Chromatography (MEKC).- 6.1 Fundamentals of MEKC.- 6.2 Optimization of Resolution.- 6.3 Selection of the Detergent.- 6.4 Separations by MEKC.- 7 Separation of Enantiomers by CE.- 7.1 Enantiomeric Separations with Cyclodextrins as Chiral Selectors.- 7.2 Other Separation Systems.- 8 Capillary Gel Electrophoresis (CGE).- 8.1 Acrylamide-based Gels.- 8.2 Polysaccharide-based Gels and other Polymers.-8.3 Migration Models of Biopolymers in Polymer Solutions.- 9 Isoelectric Focusing in Capillaries (CIEF).- 10 Other Separation Techniques in CE.- 10.1 Isotachophoresis (ITP).- 10.2 Electrochromatography (EC).- 11 A Troubleshooting Guide to CE.- 11.1 Determination of the Problem Source.- 11.2 Scenarios of Problems: What to do if....- 12 Literature Index.- 12.1 Literature Cited.- 12.2 Additional Literature Sources.- 13 Acknowledgement....