Abstract：
Nanomaterial-based synergistic antibacterial agents are considered as promising tools to combat infections caused by antibiotic-resistant bacteria. Herein, multifunctional mesoporous silica nanoparticle (MSN)-based nanocomposites were fabricated for synergistic photothermal/photodynamic/chemodynamic therapy against methicillin-resistant Staphylococcus aureus (MRSA). MSN loaded with indocyanine green (ICG) as a core, while Prussian blue (PB) nanostructure was decorated on MSN surface via in situ growth method to form a core-shell nanohybrid (MSN-ICG@PB). Upon a near infrared (NIR) laser excitation, MSN-ICG@PB (200 μg mL-1) exhibited highly efficient singlet oxygen (1O2) generation and hyperthermia effect (48.7℃). In the presence of exogenous H2O2, PB with peroxidase-like activity promoted the generation of toxic hydroxyl radicals (•OH) to achieve chemodynamic therapy (CDT). PTT can greatly increase the permeability of bacterial lipid membrane, facilitating the generated 1O2 and •OH to kill bacteria more efficiently. Under NIR irradiation and exogenous H2O2, MSN-ICG@PB (200 μg mL-1) with good biocompatibility exhibited a synergistic antibacterial effect against MRSA with high bacterial killing efficiency (>98 %). Moreover, due to the synergistic bactericidal mechanism, MSN-ICG@PB with satisfactory biosafety makes it a promising antimicrobial agent to fight against MRSA.
摘要：
基于纳米材料的协同抗菌剂被认为是对抗由抗生素抗性细菌引起的感染的有前途的工具。在这里，制备了多功能介孔二氧化硅纳米颗粒（MSN）基纳米复合材料，用于协同光热/光动力/化学动力学治疗耐甲氧西林金黄色葡萄球菌（MRSA）。以吲哚菁绿（ICG）为核心的MSN，而普鲁士蓝（PB）纳米结构通过原位生长方法装饰在MSN表面，形成核壳纳米杂化物（MSN-ICG@PB）。在近红外（NIR）激光激发下，MSN-ICG@PB（200μgmL-1）具有高效的单线态氧（1O2）生成和高温效应（48.7℃）。在外源性H2O2存在下，具有过氧化物酶样活性的PB促进了毒性羟基自由基（•OH）的产生，从而实现了化学动力学治疗（CDT）。PTT可以大大增加细菌脂质膜的通透性，促进产生的1O2和·OH更有效地杀死细菌。在NIR和外源H2O2照射下，具有良好生物相容性的MSN-ICG@PB（200μgmL-1）对MRSA表现出协同抗菌作用，具有较高的杀菌效率（>98％）。此外，由于协同杀菌机制，MSN-ICG@PB具有令人满意的生物安全性，使其成为对抗MRSA的有前途的抗微生物剂。
