Sorbact Foam Dressing Sorbact® Foam Dressing is a sterile, bacteria and fungi-binding foam dressing. It consists of a green Sorbact® wound contact layer combined with a polyurethane foam with a semi-permeable backing film. Sorbact® Foam Dressing absorbs and retains exudate, thereby reducing the risk of maceration and enabling a moist wound environment. The semi permeable backing film allows excess fluid to evaporate.