伤口感染细菌,如果不及时治疗,有可能升级到危及生命的状况,比如败血症,其特征是广泛的炎症和器官损伤。治疗细菌感染伤口的综合方法,包括控制细菌感染,生物膜根除,和炎症调节,具有重要意义。在这里,已经开发了微针(MN)贴片(FM@STMN),以丝素蛋白(SF)和基于单宁酸的水凝胶作为基质。封装在MNs内的是基于AIEgen的可激活探针(FQ-H2O2)和NLRP3抑制剂MCC950,用作光学报告剂/抗菌剂和炎症调节剂,分别。当应用于细菌感染的伤口时,FM@STMN中的MN穿透细菌生物膜并逐渐降解,释放FQ-H2O2和MCC950。释放的FQ-H2O2响应伤口部位内源性过表达的活性氧(H2O2),产生发色团FQ-OH,发出明显的NIR-II荧光和光声信号,使实时成像的结果监测;和这种发色团也表现出强大的抗菌能力,由于其双重正电荷和显示可忽略的抗菌抗性。然而,NLRP3抑制剂MCC950在释放时,抑制NLRP3炎性体的激活,从而减轻细菌感染引发的炎症并促进伤口愈合。此外,FM@STMN中的SF通过促进表皮细胞和成纤维细胞的增殖以及胶原蛋白的合成来帮助组织修复和再生。这个MN系统,没有抗生素,有望成为治疗和监测细菌感染伤口的解决方案,而不会带来抗菌素耐药性的相关风险。
Wounds infected with bacteria, if left untreated, have the potential to escalate into life-threatening conditions, such as sepsis, which is characterized by widespread inflammation and organ damage. A comprehensive approach to treating bacterial-infected wounds, encompassing the control of bacterial infection, biofilm eradication, and inflammation regulation, holds significant importance. Herein, a microneedle (MN) patch (FM@ST MN) has been developed, with silk fibroin (SF) and tannic acid-based hydrogel serving as the matrix. Encapsulated within the MNs are the AIEgen-based activatable probe (FQ-H2O2) and the NLRP3 inhibitor MCC950, serving as the optical reporter/antibacterial agent and the inflammation regulator, respectively. When applied onto bacterial-infected wounds, the MNs in FM@ST MN penetrate bacterial biofilms and gradually degrade, releasing FQ-H2O2 and MCC950. The released FQ-H2O2 responds to endogenously overexpressed reactive oxygen species (H2O2) at the wound site, generating a chromophore FQ-OH which emits noticeable NIR-II fluorescence and optoacoustic signals, enabling real-time imaging for outcome monitoring; and this chromophore also exhibits potent antibacterial capability due to its dual positive charges and shows negligible antibacterial resistance. However, the NLRP3 inhibitor MCC950, upon release, suppresses the activation of NLRP3 inflammasomes, thereby mitigating the inflammation triggered by bacterial infections and facilitating wound healing. Furthermore, SF in FM@ST MN aids in tissue repair and regeneration by promoting the proliferation of epidermal cells and fibroblasts and collagen synthesis. This MN system, free from antibiotics, holds promise as a solution for treating and monitoring bacterially infected wounds without the associated risk of antimicrobial resistance.