Evaluation of catalytic and cytotoxic behaviors of Bismuth oxide-reduced graphene oxide nanocomposites synthesized by Swietenia macrophylla plant extract

In this article, we have focused on two goals of sustainable development, namely, the provision of clean water and cytotoxic behavior of the nanomaterials on Drosophila melanogaster fly which are for good health for human of all ages. Here, virgin Bismuth oxide nanoparticles (Bi₂O₃ NPs) and Bismuth oxide-reduced graphene oxide nanocomposites (Bi₂O₃-RGO) were synthesized by environment friendly green method, and the formation of these nanomaterials was confirmed by powder X-ray diffraction study, UV–Visible study, Fourier transform infrared spectroscopy study etc. Transmission electron microscopy and scanning electron microscopy studies showed the size, shape of the virgin Bi₂O₃ NPs and also the Bi₂O₃ NPs grown on RGO surface. Approximately  5–18 nm Bi₂O₃ NPs were finely distributed on RGO surface depending on the RGO content in the synthesized nanocomposites. The surface area of the nanocomposite was determined from Brunauer–Emmett–Teller study. The application of the nanomaterials in environmental remediation was demonstrated by reduction of an organic dye, 4-nitro phenol (4-NP) to 4-amino phenol (4-AP) in presence of sodium borohydride (NaBH₄). Bi₂O₃ NPs reduce 4-NP with an efficiency of 92.65% in 40 min, whereas, the two synthesized Bi₂O₃-RGO nanocomposites show greater catalytic efficiency than the virgin Bi₂O₃ NPs. The one of the synthesized nanocomposites exhibits non-hazardous effects on a model insect Drosophila melanogaster. Selected parameters for oxidative stress, antioxidant enzymes and body metabolism were considered in the current study, whose homologs are also present in human. As Drosophila demonstrates significant genetic and physiological homology with vertebrates as well as with human beings, so the non-hazardous effects of this nanocomposite mark safe for the use as an environmental remediating agent.