Conclusions
-Amylase was covalently immobilized onto MA copolymer
films maintaining activity to hydrolyze starch. The enzymatic
properties and stability of the bioactive layers depended on the
immobilized enzyme amount and on the physicochemical properties
of the polymer carrier. The hydrophilic, high-swelling PEMA
copolymer film was found advantageous since it allowed higher
immobilized amounts and activity. The enzyme layers prepared
using the hydrophilic polymer substrate were also more stable than
the layers prepared onto hydrophobic POMA copolymer films. In
this last case, the substrate favours enzyme inactivation possibly
due to the strong hydrophobic interactions between the polymer
surface and the hydrophobic moieties of the enzyme leading to
changes in the molecular structure of the enzyme and to loss of
activity.