Appearance of high enzyme activity in immobilized urease disc by electron beam irradiation technique

A new preparation method of immobilized urease discs for biomedical applications, which was a thin circular film (200 microns, 50mm phi), was developed. The method was achieved by electron beam irradiation of polyethyleneglycol diacrylate monomers in the addition of paper disc and bean powder as protective substance for irradiation by which a denaturation of the enzyme by irradiation was effectively prevented. The immobilized enzyme disc with a high enzyme activity (remaining activity yield), about 90%, was obtained. The enzyme activity was varied by the preparation conditions such as the thickness of paper disc, monomer concentration etc. The enzymes were trapped near the surface of the disc to be easily reacted with substrate. The trapped state of the enzymes appeared to be affected by a hydrophilicity of the polymers.