Evaluation of new adsorbed coatings when applying chiral capillary electrophoresis and the partial filling technique

When using chiral selectors and the partial filling technique in capillary electrophoresis, a suitable and reproducible suppression of the electroosmotic flow is still a challenging issue, and there are a number of reasons to find alternatives to the use of covalently coated capillaries for such a particular application. In this paper, new achiral, neutral, and water-soluble polymers are evaluated as adsorbed polymers for the suppression of electroosmotic flow (EOF) when employing chiral capillary electrophoresis and the partial filling technique. Four chiral selectors, namely a cationic cyclopeptide, vancomycin, human serum albumin and riboflavin binding protein have been chosen for this study and some analytes such as derivatized amino acids, promethazine and prilocaine have been used as test compounds. Reproducibility of migration times, resolution, and selectivity as well as efficiency are reported to critically evaluate the performance of the adsorbed coatings. Results are compared to parallel data obtained with fused-silica and polyvinyl alcohol-coated capillaries.