Nanoparticles presenting promoted catalytic activity, oxygen induction and loading capability are in high demand for effective synergistic tumor therapy. Herein, ferric-tannic acid complex nanocapsules with fine hollow microstructure (HFe-TA) are synthesized and loaded with a photosensitizer (indocyanine green, ICG) for synergistic tumor therapy. In acidic environment, ICG@HFe-TA decomposes and releases Fe³⁺ ions, TA and ICG molecules. Fe³⁺, with low catalytic activity, is effectively converted into highly catalytic Fe²⁺ by the reductant TA, enabling promoted efficacy of ˙OH induction. More importantly, the ROS (¹O₂) induction by ICG is significantly enhanced under 808 nm laser irradiation due to the O₂ byproduct of Fe³⁺/Fe²⁺ conversion. In consequence, the ICG@HFe-TA nanoparticles exhibit considerable in vitro and in vivo tumor inhibition owing to the combined effect of ˙OH and ¹O₂ induced intracellularly. This study has therefore demonstrated a potential platform enabling combined photodynamic and chemodynamic therapy with high efficacy.

中文翻译：

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具有持续的O2和ROS诱导作用的空心铁鞣酸纳米胶囊用于协同肿瘤治疗。

对于有效的协同肿瘤治疗，迫切需要表现出促进的催化活性，氧诱导和负载能力的纳米颗粒。在此，合成具有精细空心微结构（HFe-TA）的铁鞣酸复合纳米胶囊，并装载光敏剂（吲哚菁绿，ICG）以进行协同肿瘤治疗。在酸性环境中，ICG @ HFe-TA分解并释放出Fe ³⁺离子，TA和ICG分子。Fe ³⁺具有低催化活性，可通过还原剂TA有效转化为高催化Fe ²⁺，从而提高enablingOH诱导作用。更重要的是，由于O ，在808 nm激光辐照下，ICG对ROS（¹ O ₂）的诱导显着增强。₂ Fe ³⁺ / Fe ²⁺转化的副产物。因此，由于˙OH和细胞内诱导的¹ O ₂的联合作用，ICG @ HFe-TA纳米粒子在体外和体内均表现出显着的肿瘤抑制作用。因此，这项研究证明了一个潜在的平台，可以实现高效的光动力和化学动力联合治疗。