Cytocompatibility and antibacterial activity of a PHBV membrane with surface-immobilized water-soluble chitosan and chondroitin-6-sulfate

A water-soluble chitosan (WSC)/chondroitin-6-sulfate (ChS) polyelectrolyte complex (PEC) is covalently immobilized onto the surface of poly(3-hydroxybutric acid-co-3-hydroxyvaleric acid) (PHBV) membranes via ozone-induced oxidation and poly(acrylic acid) (PAA) graft polymerization. To characterize the modified membranes, X-ray photoelectron spectroscopy (XPS) and water contact angle measurements are performed. It is shown that by coupling WSC as a spacer, the amount of ChS immobilized can be significantly increased. The water contact angle decreases with the amount of PAA, WSC, and ChS immobilized, which indicates the improving hydrophilicity. After WSC- and PEC-immobilization modification, the PHBV membranes possess antibacterial activity against S. aureus, E. coli, P. aeruginosa, and Methicilin resistant Staphylocus aureus (MRSA). According to the L929 fibroblast cell growth inhibition index, the as-prepared PHBV membranes are non-cytotoxic. In addition, the in-vitro evaluation of L929 fibroblast attachment, proliferation, and viability of PEC-immobilized PHBV membranes are ascertained to be superior to those of immobilized WSC or ChS alone. The overall results demonstrate that WSC/ChS PEC immobilization can not only improve the hydrophilicity and cytocompatibility of the PHBV membrane, but also endows antibacterial activity.