Antibacterial Chitosan Hybrid Films with N-Halamine-Functionalized Graphene Oxide

Graphene, a single layer of two-dimensional carbon material, has attracted much attention due to its excellent comprehensive properties including high mechanical strength, antibacterial property, excellent thermal and electrical conductivities, high specific surface area, impermeability, etc. In this study, 3-epoxypropyl-5,5-dimethylhydantoin (GH), as a precursor of N-halamine, was synthesized and attached onto graphene oxide (GO) for enhanced antibacterial activity. The synthesized GO-GH was characterized by Fourier transform infrared spectroscopy (FT-IR), scanning electron microscopy (SEM), thermogravimetric analysis (TGA) and X-ray photoelectron spectroscopy (XPS). After chlorination treatment by household bleach solution, the chlorinated graphene oxide-3-epoxypropyl-5,5-dimethylhydantoin (GO-GH-Cl) possessed great antibacterial efficacy. The synthesized GO-GH-Cl was added to chitosan (CS) solution to produce GO-GH-Cl/CS hybrid films via a solution casting method. The as-prepared antimicrobial hybrid films showed excellent antibacterial activity and could kill 100% of S. aureus and 100% of E. coli O157:H7 within 10 min and 30 min of contact time, respectively.