Characterization and antibacterial properties of genipin-crosslinked chitosan/poly(ethylene glycol)/ZnO/Ag nanocomposites

Novel nanocomposites consisting of genipin-crosslinked chitosan (GC), poly(ethylene glycol) (PEG), zinc oxide (ZnO), and silver (Ag) nanoparticles were prepared for biomedical applications as the wound-healing materials. Various amounts of ZnO and Ag nanoparticles were dispersed in the GC/PEG hydrogel matrix without severe aggregation. The effects of composition and ZnO nanoparticles on the physicochemical properties of nanocomposite samples were evaluated by infrared analysis, X-ray diffraction, and scanning electron microscopy. GC/PEG/ZnO/Ag nanocomposite showed the pH-sensitive swelling behavior and the improved mechanical properties. The antibacterial activities of nanocomposite films were tested toward the bacterial species Escherichia coli. Pseudomonas aeruginosa, Staphylococcus aureus, and Bacillus subtilis. GC/PEG/ZnO/Ag composite films had higher antibacterial activities than GC/PEG and GC/PEG/ZnO nanocomposite films. GC/PEG/ZnO/Ag composite films have potential application as wound and burn dressings. (C) 2012 Elsevier Ltd. All rights reserved.