Zhang Lihua, Ouyang Minzhi, Zhang Yufei, Zhang Leiyi, Huang Ziyun, He Libei, Lei Yanli, Zou Zhen, Feng Feng, Yang Ronghua
School of Chemistry and Material Science, Shanxi Normal University, Linfen 041004, China.
College of Chemistry and Environmental Engineering, Shanxi Datong University, Datong 037009, China.
J Mater Chem B. 2021 Oct 6;9(38):8048-8055. doi: 10.1039/d1tb01649k.
Nano-antibacterial agents can play a critical role in chronic wound management. However, the design of an intelligent nanosystem that can provide both a visual warning of infection and precise sterilization remains a hurdle. Herein, a rod-like porphyrin-based metal-organic framework theranostic nanosystem (Zn-TCPP nanorods) is fabricated coordination chelation between tetrakis(4-carboxylphenyl)porphyrin and zinc ions. This system can show significant fluorescence activation in response to the local elevated pH shown by chronic wounds, a main indicator of wound infection. Meanwhile, under the guidance of fluorescence imaging, the highly spatiotemporally precise photodynamic inactivation of microorganisms can be carried out without the destruction of surrounding normal cells and nascent cells. The results demonstrated that the Zn-TCPP nanorods were a highly sensitive and reversible probe for sensing alkaline pH levels. Alterations in the fluorescence of the Zn-TCPP nanorods can accurately indicate the infection status and heterogeneity of infection within the wound bed. Under specific light irradiation, the Zn-TCPP nanorods can exterminate 97% of the generation of reactive oxygen species (ROS). Assays of extensive wounds demonstrate that the precise fluorescence-imaging-guided suppression of bacterial infection can significantly reduce the mouse mortality rate and accelerate wound healing. This system provides the opportunity for "precision medicine" relating to chronic wounds and some large-area wounds.
纳米抗菌剂在慢性伤口管理中可发挥关键作用。然而，设计一种既能提供感染视觉预警又能精确杀菌的智能纳米系统仍然是一个障碍。在此，通过四（4 - 羧基苯基）卟啉与锌离子之间的配位螯合作用，制备了一种基于棒状卟啉的金属 - 有机框架诊疗纳米系统（Zn - TCPP纳米棒）。该系统可对慢性伤口局部升高的pH值（伤口感染的主要指标）表现出显著的荧光激活。同时，在荧光成像的引导下，可在不破坏周围正常细胞和新生细胞的情况下，对微生物进行高度时空精确的光动力灭活。结果表明，Zn - TCPP纳米棒是一种用于检测碱性pH值水平的高灵敏度且可逆的探针。Zn - TCPP纳米棒荧光的变化能够准确指示伤口床内的感染状态和感染异质性。在特定光照射下，Zn - TCPP纳米棒可消除97%的活性氧（ROS）生成。对大面积伤口的检测表明，精确的荧光成像引导下抑制细菌感染可显著降低小鼠死亡率并加速伤口愈合。该系统为慢性伤口及一些大面积伤口的“精准医疗”提供了契机。
