Synthesis of Graphene Quantum Dot Magnesium Hydroxide Nanocomposites and Investigation of Their Antioxidant and Antimicrobial Activities.

In this paper, we synthesized graphene quantum dots magnesium hydroxide nanocomposites (GQDs/Mg(OH)). The synthesized nanocomposites were characterized by UV-Vis spectroscopy, X-ray diffraction (XRD), Scanning electron microscopy (SEM), Transmission electron microscopy (TEM), X-ray photoelectron spectroscopy (XPS), and Malvern Zetasizer. The antimicrobial and antioxidant properties of the obtained GQDs/Mg(OH) nanocomposites were investigated. GQDs/Mg(OH) nanocomposites have MIC values of 15.625 μg/mL against fungi (C. metapsilosis and C. parapsilosis) and 62.5 μg/mL against Gram (+) (S. pneumonia and E. faecalis) and Gram (-) (E. coli). The synthesized GQDs/Mg(OH) nanocomposites showed moderate antioxidant activity. The results showed that at 100-µg/mL GQDs/Mg(OH) nanocomposite concentration, the HO scavenging activity was 62.18%.