Enhanced antibacterial activity of poly(vinyl alcohol)-graphene composites via graphene oxide surfactancy

Abstract

The escalating threat of bacterial infections to human health necessitates innovative antibacterial strategies and materials. Despite this need, there is still a significant demand for materials that combine high mechanical and thermal properties with biocompatibility. To address these urgent issues, our study investigates the development of poly(vinyl alcohol) (PVA) composite with graphene flakes (GF) as fillers. The aim is to strengthen the unique properties of graphene to enhance antibacterial activity. Graphene oxide (GO) was used as a surfactant to achieve stable graphene dispersion in water, preserving its inherent properties while avoiding the drawbacks associated with common surfactants, such as property reduction and complex removal processes. In this study, the mechanical and thermal properties of PVA composites containing GO and GF are superior to those of pristine PVA. Especially, the PVA-2 composite exhibited a notable enhancement in both tensile strength and elongation at break compared with the PVA composite, with increases of 7.8% and 15% respectively. Moreover, PVA-2, 4, and 6 composites exhibit significant antibacterial efficacy, achieving 4.8 and 4.9 log CFU/cm2 for Staphylococcus aureus and Escherichia coli, respectively. These results indicate that the enhanced oxidative stress induced by GO as a surfactant, combined with the physical damage caused by the increased GF nanostructures. This study highlights the potential of PVA/GF/GO composites in biomedical and tissue engineering applications, providing a promising pathway for the development of new antibacterial materials.