Chitosan based membranes to be applied on wound healing as topical drug delivery systems were developed by graft copolymerization of acrylic acid (AA) and 2-hydroxyethyl methacrylate (HEMA) onto chitosan using cerium ammonium nitrate as chemical initiator. Evidence for graft copolymerization of the vinyl monomers onto chitosan was obtained by FTIR and DMTA. Swelling degree, cytotoxicity, thrombogenicity and haemolytic activity of these membranes were evaluated. Chitosan-graft-AA-graft-HEMA showed to be the best matrix for drug delivery systems than chitosan-graft-AA because it retains good swelling properties, but the content in HEMA has improved cytocompatibility, hemocompatibility and thrombogenic character.

Six different membranes previously prepared by the authors by graft copolymerization of acrylic acid (AA) and 2-hydroxyethylmethacrylate (HEMA) onto chitosan were characterized. The graft copolymerization of the vinyl monomers onto chitosan was confirmed by FTIR and DMTA. The chitosan used was also characterized by DMTA, which allowed addressing some questions related to the typical thermal transitions of this biopolymer. The swelling capacity of the membranes was also determined. The chitosan-graft-AA-graft-HEMA with an equimolar ratio of HEMA and AA kept good swelling capacity without compromising its physical stability, which suggests it to be the best matrix for drug delivery systems.