Surface deactivation in protein and peptide analysis by capillary electrophoresis

For the analysis of proteins and peptides in capillary electrophoresis, shielding of the analytes from the active sites of the fused silica capillary wall is often necessary. There are several strategies to avoid undesirable interaction of the analytes with the capillaries. This article reviews the current, most relevant, methods. The different approaches are classified as uncoated capillaries, dynamic coated capillaries and permanent coated capillaries, according to the final effect that is produced on the capillary surface. Permanently bonded coatings are further classified by the characteristics of electroosmotic flow that they generate at the surface of the capillary. Finally organic polymeric capillaries are discussed as they have recently been introduced successfully for the separation of proteins and peptides. Throughout, attempts have been made to emphasize the potential application and the separation conditions and how these coating strategies might be utilized for the analysis each type of protein or peptide. (C) 1999 Elsevier Science B.V. All rights reserved.