INVESTIGATION OF CHIRAL RESOLUTION USING DISPLACEMENT INTERACTIONS WITH POLYMER NETWORKS IN CAPILLARY AFFINITY ZONE ELECTROPHORESIS

The effect of displacers on the resolution of the stereoisomers folini c acid, mandelic acid and N-benzoylalanine at physiological pH using c apillary affinity zone electrophoresis is described. Bovine serum albu min (BSA) is used as a run buffer additive to incorporate stereoselect ivity into the system, while salicylates exhibiting different affiniti es for BSA are added to the electrolyte for the displacement studies. The salicylate, alpha-resorcylic acid, was found to increase retention and stereoselectivity for the samples, while other displacers exhibit ed a negative effect on chiral resolution. Changes in effective mobili ty and resolution of stereoisomers using different displacers added to the run buffer did not correlate with reported equilibrium binding co nstants (K-b) for the displacer-BSA complexes. Protein-wall interactio ns were minimized using a combination of dextran in the supporting ele ctrolyte and capillaries derivatized with polyacrylamide. Dextran play ed a secondary role by improving resolution. The results indicate that displacers may be used to optimize chiral separations in affinity cap illary electrophoresis. In addition, the use of albumin as a pseudosta tionary phase may be used to screen drug-displacer interactions with B SA.