Guangdong Engineering & Technology Research Centre of Graphene-like Materials and Products, Department of Chemistry, College of Chemistry and Materials Science, Jinan University, Guangzhou 510632, P.R. China.
ACS Appl Mater Interfaces. 2021 May 12;13(18):21979-21993. doi: 10.1021/acsami.1c02761. Epub 2021 May 3.
Microbial contamination and the prevalence of resistant bacteria is considered a worldwide public health problem. Therefore, recently, great efforts have been made to develop photoresponsive platforms for the simultaneous photodynamic antibacterial (PDA) and photothermal antibacterial (PTA) therapy processes as mediated by specific light. However, owing to the absorption mismatches of the photothermal agents and photodynamic photosensitizers, it has been discovered that many synergistic photoresponsive antibacterial platforms cannot be excited by a single-wavelength light. In this study, silver bismuth sulfide quantum dots (AgBiS QDs) identified from the literature as a near-infrared light (NIR) that triggers bifunctional materials with simultaneous photodynamic and photothermal effects for photoresponsive bacterial killing were used. Specifically, AgBiS QDs were successfully synthesized via a bottom-up approach, using polyethylenimine (PEI) as an assistant molecule. With PEI wrapping, the attachment between the negatively charged membrane surfaces of the bacterial cells and AgBiS QDs was enhanced via the electrostatic interactions. The photodriven antibacterial activity of AgBiS QDs was then investigated against both and . The results revealed a significant reduction in bacterial survival. The killing effect was found to be independent of the AgBiS QDs, and redox potentials controlled the photogenerated electrons that thermodynamically favored the formation of multiple reactive oxygen species (ROS). A possible phototriggered antibacterial mechanism was then proposed in which the AgBiS QDs are anchored first to the bacterial surface and then induce breaking on its outer membrane by high local heat and ROS under single 808 nm NIR laser illumination to finally induce bacterial death.
微生物污染和耐药菌的流行被认为是一个全球性的公共卫生问题。因此，最近人们已经做出了巨大的努力来开发光响应平台，用于通过特定的光介导的光动力抗菌（PDA）和光热抗菌（PTA）治疗过程。然而，由于光热剂和光动力光敏剂的吸收不匹配，人们发现许多协同光响应抗菌平台不能被单波长光激发。在这项研究中，使用银铋硫化量子点（AgBiS QDs）作为近红外光（NIR），这种光可以触发具有光动力和光热双重效应的双功能材料，用于光响应杀菌。具体来说，AgBiS QDs 是通过自下而上的方法，使用聚乙烯亚胺（PEI）作为辅助分子成功合成的。通过 PEI 包裹，AgBiS QDs 与带负电荷的细菌细胞膜表面之间的静电相互作用增强了它们之间的附着。然后研究了 AgBiS QDs 的光驱动抗菌活性对 和 的影响。结果表明，细菌的存活率显著降低。研究发现，这种杀菌效果与 AgBiS QDs 无关，而氧化还原电位控制着光生电子，这些电子在热力学上有利于形成多种活性氧（ROS）。然后提出了一种可能的光触发抗菌机制，其中 AgBiS QDs 首先锚定在细菌表面，然后在单 808nm NIR 激光照射下通过高局部热量和 ROS 诱导其外膜破裂，最终导致细菌死亡。
