Key Laboratory of Medicinal Chemistry and Molecular Diagnosis of the Ministry of Education, Institute of Life Science and Green Development, Chemical Biology Key Laboratory of Hebei Province, College of Chemistry & Environmental Science, Hebei University, Baoding 071002, P.R. China.
Department of Radiology, Tianjin First Central Hospital, Tianjin 300192, P.R. China.
ACS Appl Mater Interfaces. 2021 Apr 7;13(13):14928-14937. doi: 10.1021/acsami.1c00430. Epub 2021 Mar 24.
In order to achieve safe and high-efficient photodynamic therapy (PDT), it was a powerful strategy of constructing O-generated nanozyme with intelligent "off/on" modulation and enhancement. Herein, a kind of HO-responsive nanozyme was developed for off/on modulation and enhancement of magnetic resonance (MR) imaging and PDT, in which great amounts of gold nanoclusters (AuNCs) were loaded into mesoporous silica to form nanoassembly, and manganese dioxide (MnO) nanosheets were wrapped as switching shield shell (AuNCs@mSiO@MnO). In a neutral physiological environment, stable MnO shells eliminated singlet oxygen (O) generation to switch off PDT and MR imaging. However, in an acidic tumor microenvironment, the MnO shell reacted with HO, in which MnO degradation switched on MR imaging and PDT, and the generated O further enhanced PDT. HO-responsive MnO degradation brought about excellent MR imaging with a longitudinal relaxation rate of 25.31 mM s, and simultaneously sufficient O generation guaranteed a 74% high O yield. Under the irradiation of a 635 nm laser, the viability of MDA-MB-435 cells was reduced to 4%, and the tumors completely disappeared, demonstrating strong PDT performance. Therefore, HO-responsive AuNCs@mSiO@MnO nanozyme showed excellent off/on modulation and enhancement of MR imaging and PDT and was a promising intelligent nanoprobe for safe and high-efficiency theranostics.
为了实现安全高效的光动力疗法（PDT），构建具有智能“开/关”调制和增强功能的 O 生成纳米酶是一种强大的策略。在此，开发了一种 HO 响应型纳米酶，用于磁共振（MR）成像和 PDT 的开/关调制和增强，其中大量的金纳米簇（AuNCs）被负载到介孔硅中以形成纳米组装体，并且二氧化锰（MnO）纳米片被包裹作为开关屏蔽壳（AuNCs@mSiO@MnO）。在中性生理环境中，稳定的 MnO 壳消除了单线态氧（O）的产生，从而关闭了 PDT 和 MR 成像。然而，在酸性肿瘤微环境中，MnO 壳与 HO 反应，其中 MnO 的降解打开了 MR 成像和 PDT，并且生成的 O 进一步增强了 PDT。HO 响应性 MnO 降解带来了出色的 MR 成像，纵向弛豫率为 25.31 mM s，同时产生了足够的 O，保证了 74%的高 O 产量。在 635nm 激光照射下，MDA-MB-435 细胞的存活率降低至 4%，肿瘤完全消失，显示出强大的 PDT 性能。因此，HO 响应性 AuNCs@mSiO@MnO 纳米酶表现出出色的 MR 成像和 PDT 的开/关调制和增强功能，是一种有前途的安全高效治疗的智能纳米探针。
