Antiangiogenesis-Combined Photothermal Therapy in the Second Near-Infrared Window at Laser Powers Below the Skin Tolerance Threshold

摘要

Photothermal agents with strong light absorption in the second near-infrared(NIR-II)region(1000-1350 nm)are strongly desired for successful photothermal therapy(PTT).In this work,titania-coated Au nanobipyramids(NBP@TiO2)with a strong plasmon resonance in the NIR-II window were synthesized.The NBP@TiO2 nanostructures have a high photothermal conversion efficiency of(93.3±5.2)%under 1064-nm laser irradiation.They are also capable for loading an anticancer drug combretastatin A-4 phosphate(CA4P).In vitro PTT studies reveal that 1064-nm laser irradiation can efficiently ablate human lung cancer A549 cells and enhance the anticancer effect of CA4P.Moreover,the CA4P-loaded NBP@TiO2 nanostructures combined with PTT induce a synergistic antiangiogenesis effect.In vivo studies show that such CA4Ploaded NBP@TiO2 nanostructures under mild 1064-nm laser irradiation at an optical power density of 0.4 W cm?2,which is lower than the skin tolerance threshold value,exhibit a superior antitumor effect.This work presents not only the development of the NBP@TiO2 nanostructures as a novel photothermal agent responsive in the NIR-II window but also a unique combined chemo-photothermal therapy strategy for cancer therapy.