▎ 摘　　要

Designing hybrid nanomaterials that exhibit multiple mechanisms of antibacterial action provides a new paradigm in the fight against resistant bacteria. Herein, we present such a new hybrid nanomaterial which integrates the antibacterial and physico-chemical properties of silver nanoparticles, graphene oxide and chitosan biopolymer. The formation, stability and structure of the integrated three-component chitosan-silver nanoparticles-graphene oxide (chit-AgNPs-GO) nanomaterial is analyzed by UV-vis extinction spectroscopy, transmission electron microscopy (TEM), X-ray photoelectron spectroscopy (XPS) and zeta potential measurements. The antibacterial activity is evaluated against two representative methicillin-resistant Staphylococcus aureus (MRSA) strains (UCLA 8076 and 1190R) and relative to individual components (GO, chit-GO, AgNPs-GO) by determining the minimum inhibitory concentration (MIC) and the minimum bactericidal concentration (MBC). The three-component nanocomposites (chit-AgNPs-GO) exhibit higher antibacterial activity than most of the antibacterial agents based on AgNPs or AgNPs-GO reported so far and, more interestingly, their activity can be controlled by the ratio between the amount of chitosan and AgNPs-GO. The results presented in this study demonstrate the promising potential of the chit-AgNps-GO hybrids as effective nanomaterial to fight against the bacterial infections. (C) 2015 Elsevier B.V. All rights reserved.