Affinity chromatography of beta-galactosidase on controlled-pore glass derivatives

Several controlled-pore glass (CPG) derivatives were examined as supports for the affinity chromatographic purification of the enzyme beta-galactosidase. The competitive inhibitor p-aminophenyl-beta-D-thiogalactopyranoside was coupled to an azelaic acid and a malonic acid derivative of 750-A alkylamine CPG of 80-120 mesh and to an azelaic acid derivative of 550-A alkylamine CPG of 40-80 mesh. The latter derivative exhibited particularly good load capacity and separation efficiency; however, both arm lengths were effective. Hydrophobic interactions between the arm and the enzyme contribute to the separation.