Abstract
In this chapter, the properties of tailor-made anionic exchanger resins based on films of large polyethylenimine polymers (e.g., molecular weight 25,000) as supports for strong but reversible immobilization of proteins are shown. The polymer is completely coated, via covalent immobilization, the surface of different porous supports. Proteins can interact with this polymeric bed, involving a large percentage of the protein surface in the adsorption. Different enzymes have been very strongly adsorbed on these supports, retaining enzyme activities. On the other hand, adsorption is very strong and the derivatives may be used under a wide range of pH and ionic strengths. These supports may be useful even to stabilize multimeric enzymes, by involving several enzyme subunits in the immobilization.