Spacer Effects on Enzymatic Activity Immobilized onto Polymeric Substrates

Abstract

Papain, chymotrypsin, and lipoprotein lipase were covalently immobilized onto the surface of polymeric beads with spacers of different lengths. The enzymes immobilized with spacer gave an almost constant activity in marked contrast with the free enzymes whose activity monotonously decreased with the decreasing surface concentration. The activity of the immobilized enzymes for hydrolysis of a high molecular weight substrate greatly depended on the length of the spacer. The pH, thermal, and storage stabilities of the immobilized enzymes were higher than those of the free ones and the enzymes immobilized directly to the bead surfaces without any spacer gave the higher stability than those immobilized with spacer. The spacer effect on the activity could be explained in terms of the mobility of the immobilized enzymes.