| In this study, we report a facile green-synthesis route for the fabrication of reduced graphene oxide
(rGO) using biomass of Brassica oleracea var. gongylodes (B. oleracea). In addition, we have attempted
to provide a green synthesis approach to prepare Gold nanoparticles (Au NPs) on the surface of
rGO by using stem extract of B. oleracea. The synthesized Au/rGO nanocomposite was evaluated
using UV–visible and FTIR spectroscopy, XRD, Raman, FE-SEM, EDX, AFM and DLS techniques. The
obtained results demonstrated that the synthesized Au NPs on the surface of rGO was spherical with
sizes ranging about 12–18 nm. The Au/rGO NC was, also, developed as photo-synthesizer system for
the photothermal therapy (PTT) of MCF7 breast cancer cells. The near-infrared (NIR) photothermal
properties of Au/rGO NCs was evaluated using a continuous laser at 808 nm with power densities
of 1 W.cm−2. Their photothermal efficacy on MCF7 breast cancer cells after optimizing the proper
concentration of the NCs were evaluated by MTT assay, Cell cycle and DAPI staining. In addition,
the potential of the synthesized Au/rGO NCs on reactive oxygen species generating and antioxidant
activity were assessed by DPPH. Au/rGO NCs possess high capacity to light-to-heat conversion for
absorption in range NIR light, and it is able to therapeutic effects on MCF7 cells at a low concentration.
The maximum amount of cell death is 40.12% which was observed in treatment groups that received
a combination of Au/rGO NCs and laser irradiation. The results demonstrate that the nanomaterials
synthesized by green approach lead to efficient destruction of cancer cell and might thus serve as an
excellent theranostic agent in Photothermal therapy applications. |