Macroporous and hydrophilic polymer resins modified with isothiocyanate groups for immobilization of enzymes

Hydrophilic and macroporous polymer resins composed of glycerylmethacrylate, styrene, and divinylbenzene were quite easily modified with isothiocyanate groups using a Friedel–Crafts reaction with 3-chloropropionyl chloride and subsequent nucleophilic reaction with KSCN. Alkaline phosphatase and trypsin could be covalently bound to the isothiocyanate-carrying polymer resins, and the immobilized enzymes obtained were sufficiently active and stable due to a covalent bonding via a spacer group between the carrier resins and the enzymes and also due to a hydrophilic environment around the enzymes. A heterogeneity of the immobilized enzyme was taken into account to interpret the thermal denaturation process of the enzyme immobilized onto the resins.