Abstract
In this work, a series of metal oxide/graphene oxide hybrid heterostructures were synthesized by a solution phase in situ method without the use of any template or surfactant. The as-synthesized materials were characterized by different characterization techniques such as X-ray diffraction, Fourier transform infrared spectroscopy (FTIR), Raman and transmission electron microscopy (TEM). It was found that the surface of graphene oxide was decorated highly by different metal oxide (MeO) nanoparticles. Further, thermogravimetric analysis (TGA) measurements showed the enhanced thermal stability of graphene oxide (GO) with respect to oxygen functional groups in composites. The as-synthesized materials, i.e., GO, pure MeO and MeO/GO nanocomposites were examined for antioxidant activity using in vitro 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical assay. Considerable in vitro antioxidant activities in a concentration-dependent manner were recorded. Interestingly, composite TiO
2
-GO showed more elevated scavenging efficiency than GO in DPPH tests. Also, in vitro anti-inflammatory activity of MeO-GO nanocomposites was evaluated using inhibition of protein denaturation. The nanocomposites CdO/GO and Ag
2
O/GO show significant increase in the protein denaturation inhibition ability when compared with GO.
Graphic abstract