Enantioselectivity properties of human serum albumin immobilized on anion-exchangers based on polyvinylimidazole-coated silica. Effect of protein loading on separation properties.

Chiral chromatographic supports were obtained by continuously applying solutions contained HSA to ion-exchange columns. The columns were packed with silica modified with polyvinylimidazole and a copolymer polyvinylpyrrolidone-polyvinylimidazole (75:25) respectively, quaternized and crosslinked. Small changes in the concentration of NaCl during immobilization of HSA lead to variations in the amount of HSA bound to the supports. These variations have consequences in terms of chromatographic retention (k'), selectivity (alpha) and resolution (Rs) of enantiomers. The effects of varying the pH and organic modifier of the mobile phase on the chromatographic properties were also examined.