OPTIMIZATION OF RESOLUTION IN CAPILLARY ZONE ELECTROPHORESIS - EFFECTOF SOLUTE MOBILITY AND BUFFER PH

A reformulated version of the resolution equation in CZE that explicit ly relates resolution to migration time is presented. Selectivity and resolution are enhanced with increasing migration time if the increase in time is a result of independent manipulation of electroosmotic flo w. If the increase in migration time is a result of simultaneous chang es in electroosmotic flow and electrophoretic mobility, selectivity an d resolution deteriorate with increasing migration time. Optimum resol ution for organic acid isomers is attained at a pH value that is about 0.3 units lower than the average pK of the two acids, even though sel ectivity continuously increases with decreasing pH. Both selectivity a nd resolution deteriorate with increasing electroosmotic flow in the s ame direction as electrophoretic mobility, however, selectivity is mor e sensitive than resolution to such changes.