The development of enzyme immobilization techniques that will not affect 
catalytic activity and conformation is an important research task. Affinity tags 
that are present or added at a specific position far from the active site in the 
structure of the native enzyme could be used to create strong affinity bonds 
between the protein structure and a surface functionalized with the 
complementary affinity ligand. These immobilization techniques are based on 
affinity interactions between biotin and (strept)avidin molecules, lectins and 
sugars, or metal chelate and histidine tag. Recent developments involve 
immobilization of tagged enzymes onto magnetic nanoparticles. These supports can 
improve the performance of immobilized biomolecules in analytical assay because 
magnetic beads provide a relative large numbers of binding sites for biochemical 
reactions resulting in faster assay kinetics. This chapter describes 
immobilization procedures of tagged enzymes onto various magnetic beads.