Immobilization of Enzymes by Entrapment - In this approach, enzyme molecules are held or entrapped within suitable gels or fibres and there mayor may not be covalent bond formation between the enzyme molecules and the matrix.

A noncovalent entrapment may be viewed as putting the enzyme molecule in a molecular cage just as a caged bird/animal. When covalent binding is also to be generated, the enzyme molecules are usually treated with a suitable reagent. Enzyme loading is very high (1 g/g gel or fiber). However, diffusion of the substrate to the enzyme and of the product away from the enzyme creates difficulties.