Simultaneous use of urea and acetonitrile as organic modifiers for optimization of resolution in micellar electrokinetic chromatography

Optimization of the resolution of non-polar solutes in micellar electrokinetic chromatography (MEKC) via the simultaneous use of the modifiers acetonitrile and urea is presented. The influence of the applied modifiers on retention factors and the ratio of the migration time of the mobile phase/migration time of the micelles (t(0)/t(MC)), which is substantial for resolution control, is described. It is shown that with high modifier concentrations, an almost infinite elution range is approached. Applying a computer-aided optimization scheme, the separation of biogenic amines derivatized with dansyl chloride is optimized using an iterative regression strategy. (C) 1997 Elsevier Science B.V.