Nanocomposite framework of chitosan/polyvinyl alcohol/ZnO: Preparation, characterization, swelling and antimicrobial evaluation

Chitosan was prepared by deactylation of chitin. Chitosan (CH)/polyvinyl alcohol (PVA) hydrogel and CH/PVA/ZnO nanocomposite were prepared using gluteraldehyde as crosslinking agent. The structures of CH, CH/PVA and CH/PVA/ZnO were investigated using Fourier transformer infrared spectroscopy (FTIR) and scanning electron microscopy (SEM). The factors affect the swelling properties of the prepared polymers were studied including: cross linker ratio, temperature, pH and immersion time. The properties of the prepared hydrogels were studied and discussed including the mechanical properties and the thermal stability. The evaluated biocidal activities of the different compounds were performed using inhibition zone diameter measurements. The antimicrobial activities of the prepared CH/PVA polymer were higher than the conventional biocides of Erythromycin and Metronidazole; while the activity was highly improved after ZnO nanocomposites formation. It was found that the increase of ZnO ratio in the formed nanocomposite increases their antimicrobial activities against gram positive and gram negative bacteria. (C) 2017 Published by Elsevier B.V.