Hydrous RuO2 nanoparticles as an efficient NIR-light induced photothermal agent for ablation of cancer cells in vitro and in vivo

RuO2 nanoparticles with characteristic plasmonic absorption exhibit an enhanced photo-thermal conversion efficiency and can be employed as a new photothermal therapy agent. Herein, hydrous RuO2 nanoparticles were synthesized by a facile hydrothermal treatment and surface-modified with a polyvinylpyrrolidone (PVP) coating. PVP-coated RuO2 nanoparticles exhibit good dispersion in saline solution, strong characteristic plasmonic absorption in the near-infrared (NIR) region, an enhanced photothermal conversion efficiency of 54.8% and remarkable photostability under irradiation by an 808 nm laser. The nanoparticles were further employed as a new photothermal ablation agent for cancer cells which led rapidly to cellular deaths both in vitro and in vivo.