Xiu Weijun, Gan Siyu, Wen Qirui, Qiu Qiu, Dai Sulai, Dong Heng, Li Qiang, Yuwen Lihui, Weng Lixing, Teng Zhaogang, Mou Yongbin, Wang Lianhui
Key Laboratory for Organic Electronics and Information Displays & Jiangsu Key Laboratory for Biosensors, Institute of Advanced Materials (IAM), Jiangsu National Synergetic Innovation Centre for Advanced Materials (SICAM), Nanjing University of Posts and Telecommunications, Nanjing 210023, China.
Department of Oral Implantology, Nanjing Stomatological Hospital, School of Medicine, Nanjing University, Nanjing 210023, China.
Research (Wash D C). 2020 Apr 12;2020:9426453. doi: 10.34133/2020/9426453. eCollection 2020.
The formation of bacterial biofilms closely associates with infectious diseases. Until now, precise diagnosis and effective treatment of bacterial biofilm infections are still in great need. Herein, a novel multifunctional theranostic nanoplatform based on MnO nanosheets (MnO NSs) has been designed to achieve pH-responsive dual-mode imaging and hypoxia-relief-enhanced antimicrobial photodynamic therapy (aPDT) of bacterial biofilm infections. In this study, MnO NSs were modified with bovine serum albumin (BSA) and polyethylene glycol (PEG) and then loaded with chlorin e6 (Ce6) as photosensitizer to form MnO-BSA/PEG-Ce6 nanosheets (MBP-Ce6 NSs). After being delivered into the bacterial biofilm-infected tissues, the MBP-Ce6 NSs could be decomposed in acidic biofilm microenvironment and release Ce6 with Mn, which subsequently activate both fluorescence (FL) and magnetic resonance (MR) signals for effective dual-mode FL/MR imaging of bacterial biofilm infections. Meanwhile, MnO could catalyze the decomposing of HO in biofilm-infected tissues into O and relieve the hypoxic condition of biofilm, which significantly enhances the efficacy of aPDT. An study showed that MBP-Ce6 NSs could significantly reduce the number of methicillin-resistant S (MRSA) in biofilms after 635 nm laser irradiation. Guided by FL/MR imaging, MRSA biofilm-infected mice can be efficiently treated by MBP-Ce6 NSs-based aPDT. Overall, MBP-Ce6 NSs not only possess biofilm microenvironment-responsive dual-mode FL/MR imaging ability but also have significantly enhanced aPDT efficacy by relieving the hypoxia habitat of biofilm, which provides a promising theranostic nanoplatform for bacterial biofilm infections.
细菌生物膜的形成与传染病密切相关。迄今为止，对细菌生物膜感染的精确诊断和有效治疗仍有巨大需求。在此，一种基于MnO纳米片（MnO NSs）的新型多功能诊疗纳米平台被设计用于实现细菌生物膜感染的pH响应双模态成像以及缺氧缓解增强型抗菌光动力疗法（aPDT）。在本研究中，MnO NSs用牛血清白蛋白（BSA）和聚乙二醇（PEG）进行修饰，然后负载二氢卟吩e6（Ce6）作为光敏剂，形成MnO-BSA/PEG-Ce6纳米片（MBP-Ce6 NSs）。将MBP-Ce6 NSs递送至细菌生物膜感染的组织后，其可在酸性生物膜微环境中分解并释放出Ce6和Mn，随后激活荧光（FL）和磁共振（MR）信号，用于细菌生物膜感染的有效双模态FL/MR成像。同时，MnO可催化生物膜感染组织中的HO分解为O，缓解生物膜的缺氧状况，显著增强aPDT的疗效。一项研究表明，635 nm激光照射后，MBP-Ce6 NSs可显著减少生物膜中耐甲氧西林金黄色葡萄球菌（MRSA）的数量。在FL/MR成像的引导下，基于MBP-Ce6 NSs的aPDT可有效治疗MRSA生物膜感染小鼠。总体而言，MBP-Ce6 NSs不仅具有生物膜微环境响应双模态FL/MR成像能力，还通过缓解生物膜的缺氧环境显著增强了aPDT疗效，为细菌生物膜感染提供了一个有前景的诊疗纳米平台。
