Abstract Bacterial infections are becoming a serious public health challenge because the abuse of antibiotics worldwide has caused bacterial resistance and the occurrence of superbugs. In this work, a new near-infrared (NIR) photoresponsive coating was constructed on Ti implant material, which was composed of MnO2, IR780 photosensitizer and polydopamine (PDA). Under the irradiation of 808 nm NIR light, the component of MnO2 in the coating exhibited high photothermal performance, and IR780 could be stimulated to generate ROS as a photosensitizer. The addition of PDA not only improved the cytocompatibility of the composite coating but also strengthened the light absorption ability of the system. Under the irradiation of 808 nm NIR light for 15 min, the composite coating killed 99.94% Staphylococcus aureus and 99.89% Escherichia coli on Ti plates. This rapid and highly effective bactericidal rate was ascribed to the synergistic effects of photothermal performance and photodynamic effect of the coatings excited by NIR light. Cell culture tests showed that PDA/IR780@MnO2–Ti had good cytocompatibility due to the excellent biocompatibility of PDA and nanostructured surface. Therefore, this surface system will be a very promising plateform to safely and effectively kill bacteria on biomedical devices and implants in a short time.

中文翻译：

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聚多巴胺/IR780@MnO2-Ti近红外快速高效杀菌

摘要 细菌感染正成为严重的公共卫生挑战，因为全球范围内滥用抗生素导致细菌耐药性和超级细菌的出现。在这项工作中，在 Ti 植入材料上构建了一种新的近红外 (NIR) 光响应涂层，该涂层由 MnO2、IR780 光敏剂和聚多巴胺 (PDA) 组成。在808 nm NIR光的照射下，涂层中的MnO2组分表现出很高的光热性能，IR780可以作为光敏剂被激发产生ROS。PDA的加入不仅提高了复合涂层的细胞相容性，而且增强了体系的光吸收能力。在 808 nm 近红外光照射 15 min 下，复合涂层在 Ti 板上杀死了 99.94% 的金黄色葡萄球菌和 99.89% 的大肠杆菌。这种快速且高效的杀菌率归因于近红外光激发的涂层的光热性能和光动力效应的协同效应。细胞培养试验表明，PDA/IR780@MnO2-Ti由于PDA和纳米结构表面具有良好的生物相容性，因此具有良好的细胞相容性。因此，这种表面系统将是一种非常有前途的平台，可以在短时间内安全有效地杀死生物医学设备和植入物上的细菌。