SYNTHESIS OF NAD POLYSTYRENE MICROSPHERES AND APPLICATION AS A CARRIER OF GLUCOAMYRASE IMMOBILIZATION

Polystyrene microspheres with a small amount of acrylic acid (200:1) i ncorporated were synthesized by nonaqueous phase dispersion (NAD) poly merization to investigate the feasibility of use as a carrier for immo bilized enzyme. Seeded emulsion polymerization was then carried out to obtain larger cross-linked polystyrene spheres, the structure of whic h was expected to yield a favorable environment to keep the original a ctivity of the immobilized enzyme. Glucoamylase, a particular enzyme c atalyzing the hydrolysis of oligosaccharides to glucose, was immobiliz ed through peptide bonding using a carbodiimide activating agent. Thir ty percent of the enzyme activity at maximum was retained relative to free glucoamylase. The immobilized enzyme remained active after 4 mont hs, although its poor resistance to heat was not improved. (C) 1994 Jo hn Wiley & Sons, Inc.