Analytical applications of immobilized enzymes.

Several clinical laboratory methods using enzymes as reagents now may utilize immobilized enzymes. These are enzymes attached to solid surfaces by adsorption, covalent binding, cross linking or similar means. Immobilized enzymes are widely used presently in convenient tests for urine glucose and galactose or blood glucose and urea, and in serum glucose or urea determinations by automated methods. Advantages include enhanced stability, enzyme conservation, reuse and economy. Limitations in clinical analysis include the requirement for proper handling of both the immobilized enzyme and the specimen with which it is used. Immobilized enzymes of the future should aid in the new discoveries regarding sequential enzyme-catalyzed reactions in living cells and expand the utility of enzymes as reagents in analytical laboratory science.