Vancomycin-assisted green synthesis of reduced graphene oxide for antimicrobial applications

Chemical reduction of graphene oxide (GO) is a simple and inexpensive method for the large-scale production of graphene-based materials. A suitable reducing agent, especially a green reductant, is in high demand for the production of reduced GO (RGO). Vancomycin, a glycopeptide antibiotic used to treat a variety of Gram-positive bacterial infections, was used to chemically reduce GO at a weak alkaline pH. As far as we know, this is the first report of reduction of GO by a glycopeptide antibiotic. The resulting vancomycin-decorated RGO (RGO-Van) was characterized by UV-visible adsorption and Raman spectroscopies, X-ray diffraction pattern and atomic force microscopy (AFM). The antibacterial effect of the RGO-Van suspension was investigated by the bacterial growth curves. The RGO-Van sheet can be fabricated into paper-like film through vacuum filtration. The antibacterial property of the as-obtained RGO-Van film was assessed by the inhibition zone test, and the bacterial adhesion assay. The antibacterial efficacy of the RGO-Van film was also verified by treatment of wound infection caused by Staphylococcus aureus (S. aureus) in a rat infection model.