Poly(acrylamide-allyl glycidyl ether) cryogel as a novel stationary phase in dye-affinity chromatography

Poly(acrylamide-allyl glycidyl ether) [poly(AAm-AGE)] cryogel was prepared by bulk polymerization which proceeds in an aqueous solution of monomers frozen inside a glass column (cryo-polymerization). After thawing, the monolithic cryogel contains a continuous polymeric matrix having interconnected pores of 10-100 mu m size. Cibacron Blue F3GA was immobilized by covalent binding onto poly(AAm-AGE) cryogel via epoxy groups. Poly(AAm-AGE) cryogel was characterized by swelling studies, FTIR, scanning electron microscopy, and elemental analysis. The equilibrium swelling degree of the poly(AAm-AGE) monolithic cryogel was 6.84 g H2O/9 cryogel. Poly(AAm-AGE) cryogel containing 68.9 mu mol Cibacron Blue F3GA/g was used in the adsorption/desorption of human serum albumin (HSA) from aqueous solutions and human plasma. The nonspecific adsorption of HSA was very low (0.2 mg/g). The maximum amount of HSA adsorption from aqueous solution in acetate buffer was 27 mg/g at pH 5.0. Higher HSA adsorption value was obtained from human plasma (up to 74.2 mg/g). Desorption of HSA with a purity of 92% from Cibacron Blue F3GA attached poly(AAm-AGE) cryogel was achieved using 0.110 Tris/HCl buffer containing 0.5M NaCl. It was observed that HSA could be repeatedly adsorbed and desorbed with poly(AAm-AGE) cryogel without significant loss in the adsorption capacity.