Incorporation of poly(ethylene glycol) proteins into polymers

Combining polymer chemistry and enzyme catalysis can be achieved by using enzymes as co-monomers in polymerization reactions. This approach requires the protection of the enzyme from the polymerization environment, which is often organic rather than aqueous. In this chapter we describe how the modification of proteins with polyethylene glycol derivatives can prepare an enzyme for covalent incorporation into a polymer during the synthesis of that polymer. First, the polyethylene glycol serves to solubilize the enzyme in the polymerization environment. Second, the use of heterofunctional polyethylene glycols containing monomeric functionalities serves to involve the protein in the polymerization itself. Thus far, subtilisin (a key industrial enzyme used in biological detergents), thermolysin (the enzyme used for biocatalytic synthesis of aspartame) and chymotrypsin (one of the most studied enzymes commercially available) have been incorporated successfully into acrylic based materials.