EFFECTS OF ALKYLAMINES ON ELECTROOSMOTIC FLOW AND PROTEIN MIGRATION BEHAVIOR IN CAPILLARY ELECTROPHORESIS

This paper reports the use of four closely related alkylamines as runn ing electrolyte additives in capillary electrophoresis that permit the control of electroosmotic flow and protein migration behaviour in unc oated capillaries. At pH 2.5 the direction of the electroosmotic flow was anodic with all additives and at constant ionic strength its magni tude increased with increasing alkylamine concentration. The observati ons are in qualitative agreement with a previous reported theoretical model that correlates the electroosmotic mobility with the charge dens ity in the Stern region of the electric double layer, arising from the adsorption of the additive, and the charge density at the capillary w all due to dissociation of silanols.