Green Approach for the Fabrication of Dual-Functional S/N Doped Graphene Tagged Zno Nanograins for in Vitro Bioimaging and Water Pollutant Remediation

Abstract

Dual-functional S/N (sulfur and nitrogen) doped graphene-tagged zinc oxide nanograins was synthesized for bioimaging applications and light-dependent photocatalytic activity. Applying the green synthesis approach, graphene was synthesized from kimchi cabbage from hydrothermal process followed by tagging it with synthesized zinc oxide nanoparticles (ZnO-NPs). The 2D/0D heterostructure prepared by combining both exhibited exceptional advantages. Comprehensive characterizations such as TEM, SEM, XRD, FTIR, XPS, and UV-Vis spectra have been performed to confirm the structures and explore the properties of the synthesized nanocomposite.  The graphene/ZnO-NP composite produced exhibited more intense fluorescence, greater chemical stability and biocompatibility, lower cytotoxicity, and better durability than ZnO NPs confer them with potential applications in cellular imaging. Furthermore, the carbon derived from a natural source contains hydroxyl, sulfur, and nitrogen-containing functional groups on the surface, result in the S/N doping on the graphene lattice that promoted high photocatalytic activity of the heterostructure network. It also demonstrated significant antibacterial activity which confers its application in removing pathogenic contaminant bacteria. In addition, the composite had better optical properties and biocompatibility, and lower toxicity than ZnO NPs. Our findings indicate that the synthesized nanocomposite will be suitable for various biomedical and pollutant remediation due to its bright light-emitting properties and stable fluorescence.

Keywords: Graphene, Tetracycline degradation, bioimaging, zinc oxide nanoparticles, bacteria, photocatalysis