Key Laboratory of Superlight Materials and Surface Technology, Ministry of Education, College of Materials Science and Chemical Engineering, Harbin Engineering University, Harbin 150001, P. R. China.
Laboratory for Space Environment and Physical Sciences, Harbin Institute of Technology, Harbin 150001, P. R. China.
ACS Appl Mater Interfaces. 2022 May 18;14(19):21787-21799. doi: 10.1021/acsami.1c22631. Epub 2022 May 4.
As the least toxic heavy metal, monoelemental bismuth nanomaterials with several superiorities are the ideal theranostic agents. However, bismuth nanoparticles are easily oxidized by oxygen in air or media, limiting their clinical application. In contrast, the oxidization of Bi to Bi can activate the chemodynamic therapy (CDT) by transferring endogenous HO into OH. Herein, a well-designed Bi-DMSNs@PCM nanosystem was prepared via growth of Bi nanodots and a coating of phase-change material (PCM) on the surface of dendritic mesoporous silica nanoparticles (DMSNs). The coated PCM protects the Bi nanodots from oxidation by keeping them in the Bi state for more than 15 d. When irradiated using the near infrared-II (NIR-II) laser with a low power density (0.5 W/cm), the heat generated from the Bi nanodots melts the PCM shell to trigger CDT through a Fenton-like reaction, accompanied by heat-induced photothermal therapy (PTT). Notably, the CDT can also compensate for the reduced PTT effect caused by the oxidation of Bi nanodots, and a satisfactory treatment effect is realized. Additionally, photoacoustic and computed tomography imaging properties were obtained. Our strategy transfers the detrimental self-oxidation of bismuth to a beneficial therapeutic mode, enhancing the potential of Bi for clinical use.
作为毒性最低的重金属，具有多种优势的单元素铋纳米材料是理想的治疗诊断一体化试剂。然而，铋纳米颗粒很容易被空气中或介质中的氧气氧化，限制了它们的临床应用。相比之下，Bi 被氧化为 Bi 可以通过将内源性的 HO 转化为 OH 来激活化学动力学治疗（CDT）。在此，通过在树枝状介孔硅纳米颗粒（DMSNs）表面生长铋纳米点和包覆相变材料（PCM），设计了一种良好的 Bi-DMSNs@PCM 纳米系统。包覆的 PCM 使 Bi 纳米点保持在 Bi 状态，超过 15 天不被氧化。当用低功率密度（0.5 W/cm）的近红外-II（NIR-II）激光照射时，Bi 纳米点产生的热量会融化 PCM 壳，通过类芬顿反应触发 CDT，同时伴有热诱导光热治疗（PTT）。值得注意的是，CDT 还可以弥补 Bi 纳米点氧化导致的 PTT 效应降低，实现令人满意的治疗效果。此外，还获得了光声和计算机断层扫描成像特性。我们的策略将铋的有害自氧化转化为有益的治疗模式，提高了铋在临床应用中的潜力。
