Plasmonic nanoparticles coated with rGO for photothermal therapy. Schematic representation of (A) rGO coated Au nanoparticles (rGO–AuNS) and (B) rGO coated Au nanorods. HR-TEM image of (C) rGO–AuNS and (D) rGO–AuNR. (E and F) Solution temperature changes over time upon irradiation (3.0 W cm−2, 808 nm) of solutions of coated and uncoated nanoparticles and distilled water (DW). (G) Photothermal cell killing with rGO–AuNS and rGO–AuNR, measured by live/dead assay after 30 s, 2 min, and 5 min of irradiation (3.0 W cm−2, 808 nm). The dotted white line represents the boundary of the irradiated area. Reprinted with permission from ref 209. Copyright 2013 American Chemical Society.