Wei Yuping, Hung Hsiang-Chieh, Sun Fang, Bai Tao, Zhang Peng, Nowinski Ann Kate, Jiang Shaoyi
Department of Chemical Engineering, University of Washington, Seattle, WA 98195, United States; Department of Chemistry, School of Science, Tianjin University, Tianjin 300354, PR China.
Department of Chemical Engineering, University of Washington, Seattle, WA 98195, United States.
Acta Biomater. 2016 Aug;40:16-22. doi: 10.1016/j.actbio.2016.04.013. Epub 2016 Apr 7.
The aim of this work is to understand and achieve low fouling surfaces by mixing two oppositely charged polysaccharides through layer-by-layer (LBL) assembly. Diethylaminoethyl-dextran hydrochloride and alginate were employed as a model system to build LBL films. A surface plasmon resonance (SPR) biosensor was used to measure quantitatively the adsorption behavior of charged macromolecules during LBL buildup and the protein adsorption behavior of each deposited bilayer in situ in real time accordingly. Results show that LBL films have lower protein adsorption as the films are constructed above the substrate surface. These LBL films eventually reach very low fouling when they are sufficiently far from the substrate surface, where the substrate surface effect is minimized and bilayers consisting of positively and negatively charged marcromolecules are uniformly mixed. Single proteins, undiluted human blood serum and plasma and cells were tested for adsorption to LBL films with similar trends. To verify the generality of these findings, alginates of low and high molecular weights and carboxymethylcellulose as a substitute to alginate were studied with similar trends observed. These results demonstrate that oppositely charged polymers, when uniformly mixed, are able to achieve low fouling properties. Findings from this work will provide a fundamental understanding of and design principles on how to build nonfouling LBL films.
We demonstrate that protein adsorption decreases with the increase of bilayer numbers. Results indicate that oppositely charged components tend to be uniformly mixed and distinct change layers in classical layer-by-layer (LBL) theories no longer exist as LBL films are sufficiently far from the substrate surface. Findings from this work provide a fundamental understanding of and design principles on how to build nonfouling LBL films.
本工作的目的是通过逐层（LBL）组装混合两种带相反电荷的多糖来理解并实现低污染表面。采用盐酸二乙氨基乙基葡聚糖和海藻酸盐作为构建LBL膜的模型体系。使用表面等离子体共振（SPR）生物传感器实时定量测量LBL组装过程中带电大分子的吸附行为以及每个沉积双层原位的蛋白质吸附行为。结果表明，当LBL膜在基底表面上方构建时，其蛋白质吸附较低。当这些LBL膜离基底表面足够远时，基底表面效应最小化且由带正电和负电的大分子组成的双层均匀混合，最终这些LBL膜达到极低的污染程度。对单一蛋白质、未稀释的人血清和血浆以及细胞吸附到LBL膜上的情况进行了测试，结果趋势相似。为了验证这些发现的普遍性，研究了低分子量和高分子量的海藻酸盐以及作为海藻酸盐替代品的羧甲基纤维素，观察到相似的趋势。这些结果表明，带相反电荷的聚合物在均匀混合时能够实现低污染特性。本工作的发现将为如何构建无污LBL膜提供基本的理解和设计原则。
我们证明蛋白质吸附随双层数目的增加而减少。结果表明，当LBL膜离基底表面足够远时，带相反电荷的组分倾向于均匀混合，经典逐层（LBL）理论中明显的变化层不再存在。本工作的发现为如何构建无污LBL膜提供了基本的理解和设计原则。
