Potential of flow-counterbalanced capillary electrophoresis for analyticaland micropreparative separations

The potential of flow-counterbalanced capillary electrophoresis (FCCE) in c hiral and achiral separations was investigated in this work. Unlimited incr ease of the separation selectivity can be achieved for binary mixtures usin g FCCE. This was shown for the enantioseparation of (+/-)-chlorpheniramine (CHL) with carboxymethyl-beta-cyclodextrin (CM-beta-CD) as chiral selector. The other example is the separation of alpha- and beta-isomers of a dipept ide aspartame (AS). The carrier ability of the (chiral) selector or pseudos tationary phase, the electroosmotic flow (EOF), the pressure-driven flow or hydrodynamic flow can be used as a counterbalancing flow to the electropho retic mobility of the analyte or vice versa. This mechanism can also be use d for micropreparative purposes. FCCE also bears the potential for stepwise separation and fraction collection of multicomponent mixtures.