Antibacterial activity of pH-sensitive genipin cross-linked chitosan/poly(ethylene glycol)/silver nanocomposites

Novel nanocomposites consisting of genipin cross-linked chitosan (GC), poly(ethylene glycol) (PEG), and silver nanoparticles were prepared for such biomedical applications as the wound-healing materials. Various amounts of silver nanoparticles were dispersed in the GC/PEG hydrogel matrix without severe aggregation. The effects of composition and silver nanoparticles on the physico-chemical properties of samples were evaluated by infrared analysis, contact angle measurements, and swelling tests. The GC/PEG/Ag nanocomposite showed a pH-sensitive swelling behavior. The surface hydrophilicity of GC/PEG/Ag nanocomposites was improved with the increase of silver nanoparticle content. L929 cell attachment was improved in the presence of silver nanoparticles. The antimicrobial function was assessed for the GC/PEG/Ag nanocomposites containing the silver content over 100ppm. The silver nanoparticles had the dual functions of reinforcing structural stability and enhancing antimicrobial activity of GC/PEG/Ag nanocomposites. Copyright (C) 2010 John Wiley & Sons, Ltd.