Siloxane-based biocatalytic films and paints for use as reactive coatings

Abstract

We have developed a new methodology for preparing films and paints suitable for use as biocatalytic coatings. The hydrolytic enzymes pronase and α-chymotrypsin were immobilized by either sol-gel entrapment or by covalent attachment into a polydimethylsiloxane (PDMS) matrix and cast into thin films or incorporated into an oil-based paint formulation. All of the coatings retained enzymatic activity and adhered to several different materials. The enzymatic films and paintsalso exhibited higher thermostability than enzymefree in solution or covalently attached to the outer surface of PDMS. A porous membrane based on aPDMS-immobilized enzyme was also prepared by an immersion precipitation process. Protein adsorption measurements showed that the enzyme-containing films and paints adsorbed less protein than enzyme-free controls, and that protein adsorption decreased with increasing proteolytic activity of thecoating. These coatings thus provide the means toapply a stable enzymatic surface to a wide range of materials, and may be generally useful as biocatalytic paints and films. © 2001 John Wiley and Sons, Inc.