Sharma Sadhana, Desai Tejal A
Davis Heart & Lung Research Institute, The Ohio State University, Columbus, Ohio 43210, USA.
J Nanosci Nanotechnol. 2005 Feb;5(2):235-43. doi: 10.1166/jnn.2005.030.
The creation of antifouling surfaces is one of the major prerequisites for silicon-based micro-electrical-mechanical systems for biomedical and analytical applications (known as BioMEMS). Poly(ethylene glycol) (PEG), a water-soluble, nontoxic, and nonimmunogenic polymer has the unique ability to reduce nonspecific protein adsorption and cell adhesion and, therefore, is generally coupled with a wide variety of surfaces to improve their biocompatibility. To this end, we have analyzed PEG thin films of various grafting densities (i.e., number of PEG chains per unit area) coupled to silicon using a single-step PEG-silane coupling reaction scheme using variable-angle ellipsometry. Initial PEG concentration and coupling time were varied to attain different grafting densities. These data were theoretically analyzed to understand the phenomenon of PEG film formation. Furthermore, all the PEG films were evaluated for their ability to control biofouling using albumin and fibrinogen as the model proteins. PEG thin films formed by using higher PEG concentrations ( > or = 10 mM PEG) or coupling time ( > or = 1 h) demonstrated enhanced protein fouling resistance behavior. This analysis is expected to be useful to form PEG films of desired grafting density on silicon substrates for appropriate application.
创建防污表面是用于生物医学和分析应用的硅基微机电系统（即生物微机电系统）的主要先决条件之一。聚乙二醇（PEG）是一种水溶性、无毒且无免疫原性的聚合物，具有减少非特异性蛋白质吸附和细胞粘附的独特能力，因此通常与各种表面结合以提高其生物相容性。为此，我们使用可变角度椭偏仪，通过单步PEG-硅烷偶联反应方案，分析了与硅结合的各种接枝密度（即每单位面积的PEG链数）的PEG薄膜。改变初始PEG浓度和偶联时间以获得不同的接枝密度。对这些数据进行理论分析以了解PEG膜形成现象。此外，以白蛋白和纤维蛋白原为模型蛋白，评估了所有PEG膜控制生物污染的能力。使用较高PEG浓度（≥10 mM PEG）或偶联时间（≥1 h）形成的PEG薄膜表现出增强的抗蛋白质污染行为。预计该分析对于在硅基板上形成具有所需接枝密度的PEG膜以进行适当应用将是有用的。
