Amine Functionalized Graphene Quantum Dots as a Smart Nano Antibacterial Agent

Conventional antibiotics are resisted by bacteria at an increasing rate, prompting studies into the development of alternate antibiotic agents. This work demonstrates the fabrication and characterization of amine functionalized graphene quantum dots (af-GQDs) with starting materials of graphene oxide, ammonia, and hydrogen peroxide by chemical oxidation and hydrothermal methods. The synthesized af-GQDs were characterized using analytical techniques such as UV-vis, fluorescence, FTIR, Raman spectroscopy, and morphological studies through TEM. TEM images showed that af-GQDs have smooth surface morphology with porous in nature and are spherical in shape with particle size less than 20 nm. The prepared af-GQDs show a quantum yield of 26.32%. A growth inhibition test was performed on E. coli and S. aureus for the prepared af-GQDs at different increasing concentrations. The minimum inhibitory concentration for the prepared af-GQDs on E. coli was found to be 55 μg/mL and for S. aureus was found to be 35 μg/mL. Percentage cell viability studies were performed on HeLa and Jukart cells for 24 hours at different concentrations. Both cells showed maximum cell viability percentage at the initial concentration. At higher concentrations, the cell viability is decreased for both cells but the Jukart cells show a minimum percentage of cell viability at higher concentrations than the HeLa cells.