Waters A Reprint from

A resolution equation for EKC was developed starting from the resolution equation for electrophoresis. The equation was used to predict the influence of the migration window and partitioning on resolution in EKC. It is theoretically shown that the migration window can have a dramatic effect on resolution in EKC. Using a novel chiral surfactant, the influence of the migration window and partitioning on the separation of benzoin enantiomers was experimentally determined. The results obtained agreed with predictions based on the equation. The ability to obtain very high resolution values by migration window manipulation was demonstrated for the separation of N-methylpseudoephedrine enantiomers (α=1.3). Specifically, the resolution was 2.4 under conditions of robust EOF, but increased to 11 using conditions of low EOF.