Myoglobin entrapment in poly(vinyl alcohol) dense membranes

Abstract

Our goal in this study was the immobilization of myoglobin in poly(vinyl alcohol) dense membranes. Glutaraldehyde was investigated both as the crosslinking agent, aiming to increase the membrane stability in aqueous medium, and as the vehicle to bind myoglobin and PVA. Reaction and membrane synthesis were carried simultaneously in mild operating conditions in order to maintain the native protein folding. Membrane characterization comprised the water swelling degree, DSC, TGA, UV-visible spectroscopy, FTIR analysis and oxygen transport in a dialysis cell. The incorporation of myoglobin in the film decreased the water swelling degree and improved the membrane thermal properties compared to unmodified PVA membrane. The reduction of ferric iron in the prosthetic group of the protein to the ferrous form was observed. The increased affinity between oxygen and the immobilized myoglobin did not favor the release of this solute from the biocarrier.