Department of Chemistry and the Texas Center for Superconductivity and ‡Department of Electrical and Computer Engineering University of Houston , Houston, Texas 77204-5003, United States.
ACS Appl Mater Interfaces. 2015 Feb 25;7(7):3981-93. doi: 10.1021/am506516r. Epub 2015 Feb 9.
Catheter-related infections (CRIs) are associated with the formation of pathogenic biofilms on the surfaces of silicone catheters, which are ubiquitous in medicine. These biofilms provide protection against antimicrobial agents and facilitate the development of bacterial resistance to antibiotics. The application of photothermal agents on catheter surfaces is an innovative approach to overcoming biofilm-generated CRIs. Gold nanoshells (AuNSs) represent a promising photothermal tool, because they can be used to generate heat upon exposure to near-infrared (NIR) radiation, are biologically inert at physiological temperatures, and can be engineered for the photothermal ablation of cells and tissue. In this study, AuNSs functionalized with carboxylate-terminated organosulfur ligands were attached to model catheter surfaces and tested for their effectiveness at killing adhered Enterococcus faecalis (E. faecalis) bacteria. The morphology of the AuNSs was characterized by scanning electron microscopy (SEM) and transmission electron microscopy (TEM), while the elemental composition was characterized by energy-dispersive X-ray spectroscopy (EDX) and X-ray photoelectron spectroscopy (XPS). Furthermore, optical and photothermal properties were acquired by ultraviolet-visible (UV-vis) spectroscopy and thermographic imaging with an infrared camera, respectively. Bacterial survival studies on AuNS-modified surfaces irradiated with and without NIR light were evaluated using a colony-formation assay. These studies demonstrated that AuNS-modified surfaces, when illuminated with NIR light, can effectively kill E. faecalis on silicone surfaces.
导管相关感染（CRI）与硅酮导管表面致病性生物膜的形成有关，而生物膜在医学中无处不在。这些生物膜为抗生素提供了保护，并促进了细菌对抗生素的耐药性的发展。在导管表面应用光热剂是克服生物膜引起的 CRI 的创新方法。金纳米壳（AuNSs）代表了一种有前途的光热工具，因为它们可以在暴露于近红外（NIR）辐射时产生热量，在生理温度下具有生物惰性，并且可以被设计用于光热消融细胞和组织。在这项研究中，AuNSs 用羧基末端有机硫配体功能化，附着在模型导管表面上，并测试其杀死附着的粪肠球菌（E. faecalis）的效果。AuNSs 的形态通过扫描电子显微镜（SEM）和透射电子显微镜（TEM）进行了表征，而元素组成则通过能量色散 X 射线光谱（EDX）和 X 射线光电子能谱（XPS）进行了表征。此外，光学和光热特性分别通过紫外-可见（UV-vis）光谱和红外相机的热成像获得。通过平板计数法评估了在有和没有 NIR 光照射下 AuNS 修饰表面上的细菌存活研究。这些研究表明，当用 NIR 光照射时，AuNS 修饰的表面可以有效地杀死硅酮表面上的 E. faecalis。
