EQUATION FOR THE DESCRIPTION OF THE RESOLUTION OF CHARGED SOLUTES IN MICELLAR ELECTROKINETIC CAPILLARY CHROMATOGRAPHY

The migration behaviour of charged solutes in micellar electrokinetic capillary chromatography is affected by both the electrophoretic prope rties of the solute and its interaction with the micelles. Both must t herefore be considered to obtain an adequate description of the migrat ion behaviour and thus resolution. A novel equation is presented, in w hich the resolution is expressed as a function of the micellar interac tion (capacity factor for charged solutes) and the electrophoretic mob ility (free zone migration time) of the charged solute. Simulations re veal the dependence of the resolution of two closely migrating solutes on both distinct interactions, which is clearly different as compared to the separation of neutral solutes and general guidelines with resp ect to better separation are deduced. Experimental data illustrate tha t this equation can be used to gain more insight in the corresponding migration mechanisms. Furthermore, using this knowledge, it is possibl e to adjust the experimental parameters to achieve better resolution.