Enzymatically active free standing membranes based on an easy two step preparation from alginate catechol and glucose oxidase/peroxidase

Thick and robust free standing membranes were prepared by blending alginate modified with catechol groups and a mixture of two enzymes: glucose oxidase and peroxidase. The dried composite paste was crosslinked with sodium periodate, allowing to oxidize the catechol groups in quinones and to obtain thick free standing membranes. The enzymatic activity of those membranes was proportional to the mass of the used reactants, and hence to the membrane thickness, in the 100 mu m range. This was possible owing to the microporous structure of the Alg-Cat@enzyme membrane.