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 CA4P-loaded 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.

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成功地进行光热疗法（PTT）强烈需要在第二个近红外（NIR-II）区域（1000-1350 nm）具有强光吸收的光热剂。在这项工作中，合成了在NIR-II窗口中具有强等离子体共振的二氧化钛包覆的Au纳米双锥体（NBP @ TiO ₂）。在1064 nm激光辐照下，NBP @ TiO ₂纳米结构具有（93.3±5.2）％的高光热转换效率。它们还能够加载抗癌药康培他汀A-4磷酸酯（CA4P）。体外PTT研究表明，1064 nm激光照射可有效消融人肺癌A549细胞并增强CA4P的抗癌作用。此外，加载了CA4P的NBP @ TiO ₂纳米结构与PTT结合可产生协同的抗血管生成作用。体内研究表明，在低于皮肤耐受性阈值的0.4 W cm ^-2的光功率密度下，在温和的1064 nm激光辐照下，这种负载CA4P的NBP @ TiO ₂纳米结构表现出优异的抗肿瘤作用。这项工作不仅提出了NBP @ TiO ₂纳米结构作为在NIR-II窗口中响应的新型光热剂的发展，而且还提出了一种独特的联合化学光热疗法用于癌症治疗。

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