Near-infrared light-responsive nanoparticles for improved anticancer efficacy through synergistic chemo-photothermal therapy

Combined treatment is more effective than single treatment against most forms of cancer. The synergistic chemo-thermotherapy mediated by nanoparticles has superior advantages of lesser adverse effects as a promising cancer therapy modality. In this study, we report a theranostic carrier system co-encapsulating Doxorubicin (DOX) and Indocyanine green (ICG) into the D--Tocopheryl polyethylene glycol 1000 succinate (TPGS). Full physicochemical characterization studies of the DOX/ICG-loaded TPGS nanoparticles (TNPs) are performed. TNPs have a mean size around 60nm with superior photostability, and entrapment efficiency of drugs in TNPs was 75.0% for ICG and 68.3% for DOX. TNPs also exhibit a longer sustained release with around 63% of the entrapped drug in 24h. In vitro studies, TNPs could effectively enhance cellular uptake of DOX and ICG, which permitted high therapeutic efficacy against cancer cells. Further, we investigate antitumor efficacy of TNPs along with its impact on major organs in vivo, TNPs also exhibit a complete inhibition of tumor growth and minimal side effects after irradiation. Collectively, these results suggest that near-infrared light-responsive TNPs can further enhance antitumor effects by synergistic chemo-photothermal therapy.