College of Chemistry and Molecular Sciences, Wuhan University, Wuhan 430072, P. R. China.
Medical Research Institute, Wuhan University, Wuhan 430072, P. R. China.
ACS Appl Mater Interfaces. 2021 Apr 14;13(14):16075-16083. doi: 10.1021/acsami.1c01683. Epub 2021 Mar 31.
Photodynamic therapy (PDT) utilizes reactive oxygen species (ROS) to treat established diseases and has attracted growing attention in the field of cancer therapy. However, in a tumor microenvironment (TME), the inherent hypoxia and high level of antioxidants severely hamper the efficacy of ROS generation. Here, we describe a cascaded amplifier nanoreactor based on self-assembled nanofusiforms for persistent oxygenation to amplify ROS levels. The nanofusiform assembly is capable of photothermal and photodynamic treatment and regulation of redox oxidation stress by antioxidant depletion to prevent ROS tolerance. The Pt nanozyme decoration of the nanofusiform enables efficient oxygen supplements Pt nanozyme-catalyzed decomposition of HO overexpressed in TME and generation of O. Furthermore, the temperature elevation resulted from the photothermal effect of the nanofusiform increases the catalase-like catalytic activity of the Pt nanozyme for boosted oxygen generation. Thus, such a triple cascade strategy using nanozyme-based nanofusiforms amplifies the ROS level by continuous oxygenation, enhancing the efficacy of PDT and . Meanwhile, an multi-modal imaging including near-infrared fluorescence imaging, photothermal imaging, and magnetic resonance imaging achieves precise tumor diagnosis. The rationally designed nanofusiform acts as an efficient ROS amplifier through multidimension strengthening of continuous oxygenation, providing a potential smart nanodrug for cancer therapy.
光动力疗法（PDT）利用活性氧（ROS）来治疗已建立的疾病，在癌症治疗领域引起了越来越多的关注。然而，在肿瘤微环境（TME）中，固有缺氧和高水平的抗氧化剂严重阻碍了 ROS 的生成效率。在这里，我们描述了一种基于自组装纳米纤维的级联放大器纳米反应器，用于持续供氧以放大 ROS 水平。纳米纤维的组装能够进行光热和光动力治疗，并通过抗氧化剂耗竭来调节氧化还原应激，以防止 ROS 耐受。纳米纤维的 Pt 纳米酶修饰能够有效地补充氧气，Pt 纳米酶能够催化分解 TME 中过表达的 HO 并生成 O。此外，纳米纤维的光热效应引起的温度升高会增加 Pt 纳米酶的类过氧化氢酶催化活性，从而促进氧气的生成。因此，这种基于纳米酶的纳米纤维的三重级联策略通过持续供氧来放大 ROS 水平，提高 PDT 的疗效和。同时，一种多模态成像包括近红外荧光成像、光热成像和磁共振成像，实现了精确的肿瘤诊断。这种合理设计的纳米纤维通过多维强化持续供氧，作为一种有效的 ROS 放大器，为癌症治疗提供了一种潜在的智能纳米药物。
