Rose-bengal-conjugated gold nanorods for in vivo photodynamic and photothermal oral cancer therapies

Gold nanorods (GNRs) conjugated with rose bengal (RB) molecules exhibit efficient singlet oxygen generation when illuminated by 532 nm green light and high photothermal efficiency under 810 nm near-infrared (NIR) irradiation. In vitro experiments show that reactive oxygen species generated by green light and hyperthermia produced by NIR light constitute two different mechanisms for cancer cell death. The RB-GNRs also exhibit improved photodynamic efficacy by enhancing the uptake of RB by cancer cells. In vivo experiments are conducted on hamster cheek pouches to resemble the human oral cancer conditions more accurately to assess the therapeutic effectiveness. Compared to the single photodynamic therapy (PDT) or photothermal therapy (PTT), the RB-GNRs with combined PDT-PTT capabilities provide better therapeutic effects against oral cancer and have large potential in cancer treatment.