Institute of Bioadditive Manufacturing, Jiangxi University of Science and Technology, Nanchang 330013, China.
School of Materials Science and Engineering, Xihua University, Chengdu, Sichuan 610039, China.
Colloids Surf B Biointerfaces. 2023 Oct;230:113512. doi: 10.1016/j.colsurfb.2023.113512. Epub 2023 Aug 8.
Graphitic carbon nitride (g-CN) had aroused tremendous attention in photodynamic antibacterial therapy due to its excellent energy band structure and appealing optical performance. Nevertheless, the superfast electron-hole recombination and dense biofilm formation abated its photodynamic antibacterial effect. To this end, a nanoheterojunction was synthesized via in-situ growing copper sulfide (CuS) on g-CN (CuS@g-CN). On the one hand, CuS could form Fermi level difference with g-CN to accelerate carrier transfer and thus facilitate electron-hole separation. On the other hand, CuS could respond near-infrared light to generate localized thermal to disrupt biofilm. Then the CuS@g-CN nanoparticle was introduced into the poly-l-lactide (PLLA) scaffold. The photoelectrochemistry results demonstrated that the electron-hole separation efficiency was apparently enhanced and thereby brought an approximate sevenfold increase in reactive oxygen species (ROS) production. The thermal imaging indicated that the scaffold possesses a superior photothermal effect, which effectively eradicated the biofilm by disrupting its extracellular DNA and thereby facilitated to the entry of ROS. The entered ROS could effectively kill the bacteria by causing protein, K, and nucleic acid leakage and glutathione consumption. As a consequence, the scaffold displayed an antibacterial rate of 97.2% and 98.5% against E. coli and S. aureus, respectively.
石墨相氮化碳（g-CN）由于其优异的能带结构和诱人的光学性能，在光动力抗菌治疗中引起了极大的关注。然而，超快的电子-空穴复合和密集的生物膜形成削弱了其光动力抗菌效果。为此，通过在 g-CN 上原位生长硫化铜（CuS）合成了纳米异质结（CuS@g-CN）。一方面，CuS 可以与 g-CN 形成费米能级差，加速载流子转移，从而促进电子-空穴分离。另一方面，CuS 可以响应近红外光产生局部热来破坏生物膜。然后将 CuS@g-CN 纳米颗粒引入聚-L-乳酸（PLLA）支架中。光电化学结果表明，电子-空穴分离效率明显提高，从而使活性氧（ROS）的产生增加了近 7 倍。热成像表明，支架具有优异的光热效应，通过破坏其细胞外 DNA 有效地消除了生物膜，从而促进了 ROS 的进入。进入的 ROS 可以通过引起蛋白质、K 和核酸泄漏以及谷胱甘肽消耗来有效地杀死细菌。因此，支架对大肠杆菌和金黄色葡萄球菌的抗菌率分别达到 97.2%和 98.5%。
