Natural polymers: suitable carriers for enzyme immobilization

Enzyme immobilization onto support carriers is a method used to overcome some of the limitations of soluble enzymes in practical applications. Various different materials have been used as carriers, such as inorganic matrixes, natural and synthetic polymers. Production of carriers from natural biopolymers and their derivatives are the focus of numerous research worldwide, and a summary of their applications for enzyme immobilization is presented in this paper. Enzymes or cells are entrapped inside a three-dimensional polymeric network that is able to retain water in large amounts, called hydrogel. This network could be formed by chemical cross-linking, ionotropic gelling in the presence of cation or in thermo reverse polymerization, depending on the polymer in use and its characteristics. Most frequently used biopolymers as carriers for immobilization include alginate, cellulose, chitosan, collagen, xylan, pectin, starch, and others