Key Laboratory of Coal Conversion and New Carbon Materials of Hubei Province & Institute of Advanced Materials and Nanotechnology, School of Chemistry and Chemical Engineering, Wuhan University of Science and Technology, Wuhan 430081, China.
College of Chemistry & Molecular Sciences, Wuhan University, Wuhan 430072, China.
Int J Biol Macromol. 2023 Jan 1;224:1206-1216. doi: 10.1016/j.ijbiomac.2022.10.206. Epub 2022 Oct 26.
Bacterial and biofilm infections are prevalent, photothermal antibacterial therapy exploiting Ag NPs was an alternative. However, various matrix materials including polysaccharides used to stabilize Ag NPs are not efficiently utilized. In this study, catechol functionalized quaternized chitin (DQC) is first synthesized, then Ag is in situ reduced to small Ag NPs stabilized and well-dispersed by DQC to form Ag NPs-incorporated quaternized chitin (DQCA) nanomicelle in a green and simple way. The photothermal conversion efficiency of the DQCA was up to be 65 %, which was much higher than that of many reported systems. The rationally designed DQCA takes full advantage of each component, specifically, DQCA is endowed with bacterial targeting, sterilization effects of cationic groups and Ag NPs, and superior photothermal combinational bactericidal and antibiofilm activities. The in vitro antibacterial rate of DQCA with NIR laser irradiation was >95 % in 10 min (99.5 % for E. coli and 95.7 % for S. aureus, respectively), and the eradication efficiency against both of the E. coli and S. aureus biofilms reached up to 99.9 %. Moreover, full-thickness S. aureus biofilms-infected wound healing test in the mouse model demonstrates that the combinational effect of DQCA nanomicelle could significantly accelerate the wound healing, by simultaneously reducing inflammation, enhancing re-epithelialization and promoting collagen deposition. And the wound treated with DQCA plus NIR irradiation at day 15 possessed the smallest open wound (2.5 %). Collectively, these features indicate facilely fabricated DQCA nanomicelle gets the most use of each component, and could serve as an excellent alternative for bacterial infection therapy.
细菌和生物膜感染很普遍，利用 Ag NPs 的光热抗菌疗法是一种替代方法。然而，包括用于稳定 Ag NPs 的多糖在内的各种基质材料并未得到有效利用。在这项研究中，首先合成了儿茶酚功能化季铵化壳聚糖（DQC），然后通过 DQC 将 Ag 原位还原为小的 Ag NPs 并使其稳定且良好分散，从而以绿色简单的方式形成 Ag NPs 掺入的季铵化壳聚糖（DQCA）纳米胶束。DQCA 的光热转换效率高达 65%，远高于许多报道的系统。这种合理设计的 DQCA 充分利用了每个组分，具体而言，DQCA 具有细菌靶向性、阳离子基团和 Ag NPs 的杀菌效果以及优异的光热组合杀菌和抗生物膜活性。在 NIR 激光照射下，DQCA 的体外抗菌率在 10 分钟内超过 95%（大肠杆菌为 99.5%，金黄色葡萄球菌为 95.7%），对大肠杆菌和金黄色葡萄球菌生物膜的清除效率均达到 99.9%。此外，在小鼠模型中进行的全厚度金黄色葡萄球菌生物膜感染伤口愈合试验表明，DQCA 纳米胶束的组合作用可以通过同时减少炎症、增强再上皮化和促进胶原蛋白沉积来显著加速伤口愈合。在第 15 天用 DQCA 加 NIR 照射处理的伤口具有最小的开放伤口（2.5%）。总的来说，这些特征表明，易于制备的 DQCA 纳米胶束最大限度地利用了每个组分，并可以作为细菌感染治疗的一种极好的替代方法。
