Preparation, characterization and anti-cancer activity of graphene oxide-silver nanocomposite

This work reported the preparation, characterization, cytotoxicity of green synthesized Lespedeza cuneate mediated silver nanoparticles (Lc-AgNPs) and graphene oxide-silver nanocomposite (GO-AgNComp) using LcAgNPs. The UV absorption spectrum at 419 nm indicated the successful formation of GO-AgNComp. The TEM analysis displayed the thin sheet of graphene decorated Lc-AgNPs in GO-AgNComp. Zeta potential was -13.2 mV for Lc-AgNPs and -30.5 mV for GO-AgNComp. The photothermal conversion efficiency was calculated as 31.09% for GO-AgNComp. The negatively charged zeta potential of GO-AgNComp enhanced its cellular penetration through enhanced permeability and retention (EPR) effect. The near-infrared laser (NIR) induced the anticancer activity of Lc-AgNPs and GO-AgNComp in human lung cancer cells (A549) and brain tumour (LN229). The results indicated that about 50% of A549 cells and LN229 cells were ablated by treatment of 24.73 +/- 2.98 mu g/mL and 27.34 +/- 1.62 mu g/mL of Lc-AgNPs, as well by 15.46 +/- 2.31 mu g/mL and 20.95 +/- 1.35 mu g/mL of GO-AgNComp respectively. Moreover, GO-AgNComp was not cytotoxic to normal mouse fibroblast cells (NIH3T3), but it caused the cancer cell death in A549 and LN229 through ROS generation, nuclear damage, and mitochondrial membrane potential (Delta psi m) loss. This work reported the anticancer potential of GO-AgNComp, which deserves further study on the molecular elucidation of GO-AgNComp mediated human lung and tumour therapy.