CAS Key Laboratory for Biomedical Effects of Nanomaterials and Nanosafety, Institute of High Energy Physics, Chinese Academy of Sciences, Beijing 100049, People's Republic of China.
J Mater Chem B. 2020 Jan 28;8(4):666-676. doi: 10.1039/c9tb02562f. Epub 2020 Jan 6.
The non-invasive imaging of the gastrointestinal (GI) tract is highly desired for clinical research due to the various GI tract bacterial infection-induced diseases. To treat GI tract infections, various antibiotics have been used in the clinic. The growing problem of multidrug-resistant bacteria calls for effective antibiotic alternatives. Here, we construct a dual-functional BiS@mSiO@Ag nanocomposite for simultaneous enhanced X-ray computed tomography (CT) imaging and efficient antibacterial activity in the GI tract. The nanocomposite also has good stability, low cytotoxicity, and negligible hemolysis. Moreover, the investigation of the long-term toxicity and biodistribution of the BiS@mSiO@Ag nanocomposite after oral administration confirms its safety at the tested dosage. In particular, Ag nanoparticles (NPs) well dispersed on a silica substrate can reduce the antibacterial dosage and enhance the antibacterial activity of the BiS@mSiO@Ag nanocomposite. Furthermore, we have established bacterially infected enteritis animal models to confirm the antibacterial ability of the nanocomposite. This work opens up a new avenue for the design of a nanotheranostic agent that acts as both a contrast agent for the enhanced visualization of the GI tract and an antibacterial agent as an alternative to antibiotics.
由于各种胃肠道细菌感染性疾病的存在，人们非常希望对胃肠道（GI）进行非侵入性成像。为了治疗胃肠道感染，临床上已经使用了各种抗生素。越来越多的多药耐药菌问题需要有效的抗生素替代品。在这里，我们构建了一种双功能 BiS@mSiO@Ag 纳米复合材料，用于在胃肠道中同时进行增强的 X 射线计算机断层扫描（CT）成像和有效的抗菌活性。该纳米复合材料还具有良好的稳定性、低细胞毒性和可忽略的溶血作用。此外，口服给予 BiS@mSiO@Ag 纳米复合材料后的长期毒性和生物分布研究证实了其在测试剂量下的安全性。特别是，Ag 纳米颗粒（NPs）在二氧化硅基质上的良好分散可以降低抗菌剂的用量并增强 BiS@mSiO@Ag 纳米复合材料的抗菌活性。此外，我们还建立了细菌感染性肠炎动物模型，以确认纳米复合材料的抗菌能力。这项工作为设计一种既可作为胃肠道增强可视化的造影剂，又可作为抗生素替代品的抗菌剂的治疗诊断一体化纳米材料开辟了新途径。
