Enzyme immobilization: an update

Abstract

Compared to free enzymes in solution, immobilized enzymes are more robust and more resistant to environmental changes. More importantly, the heterogeneity of the immo-bilized enzyme systems allows an easy recovery of both enzymes and products, multiple re-use of enzymes, continuous operation of enzymatic processes, rapid termination of reactions, and greater variety of bioreactor designs. This paper is a review of the recent literatures on enzyme immobilization by various techniques, the need for immobilization and different applications in industry, covering the last two decades. The most recent papers, patents, and reviews on immobilization strategies and application are reviewed.

Keywords: Biocatalyst; Enzyme immobilization; Enzyme reuse.

Fig. 1

Selective approaches employing affinity reagents

Fig. 2

Some methods used for enzyme immobilization

Fig. 3

Hydrogen bonds between carbonyl groups and the –NH groups of the polypeptidic chain

Fig. 4

Reaction of maleimide forming chemical conjugation to a sulfhydryl

Fig. 5

The “click” chemistry reaction of alkyne (1) with azide (2) to form a 1,4-disubstituted 1,2,3-triazol

Fig. 6

The “photoclick chemistry” between tetrazoles and alkenes to form pyrazoline

Fig. 7

Structure of polyacrylamide gel matrix

Fig. 8

Chemical structures of cellulose and its amino derivatives

Fig. 9

Porphyrin–gold nanoparticle (AuNP)