ABSTRACT
This chapter focuses on practical uses for isolated enzymes and dead cells. The properties of immobilized enzymes and their free predecessors differ primarily because the former no longer constitute a homogeneous and isotropic enzymatic system. The concept of nonequal distribution of components of enzymatic reactions between the immobilized enzyme and outer solution phases is applicable not only to electrostatic but to other types of interactions as well. Living cells must have their metabolic machinery substantially intact and also be capable of reproduction. Stirring free cells in an aqueous solution eventually results in their rupture, which leads to solubilization and, consequently, destabilization of the enzymes. The scope of enzyme technology is indicated by a list of the types of reactions catalyzed by enzymes. Methods of immobilization such as adsorption and gel entrapment are very simple and efficient, but since such methods create no strong bonds between the enzyme and the matrix, enzymes often leak from the supports.
