He Yi, Hower Jason, Chen Shengfu, Bernards Matthew T, Chang Yung, Jiang Shaoyi
Department of Chemical Engineering, University of Washington, Seattle, WA 98195, USA.
Langmuir. 2008 Sep 16;24(18):10358-64. doi: 10.1021/la8013046. Epub 2008 Aug 9.
Molecular simulations were performed to study the interactions between a protein (lysozyme, LYZ) and phosphorylcholine-terminated self-assembled monolayers (PC-SAMs) in the presence of explicit water molecules and ions. The results show that the water molecules above the PC-SAM surface create a strong repulsive force on the protein as it approaches the surface. The structural and dynamic properties of the water molecules above the PC-SAM surface were analyzed to provide information regarding the role of hydration in surface resistance to protein adsorption. It can be seen from residence time dynamics that the water molecules immediately above the PC-SAM surface are significantly slowed down as compared to bulk water, suggesting that the PC-SAM surface generates a tightly bound, structured water layer around its head groups. Moreover, the orientational distribution and reorientational dynamics of the interfacial water molecules near the PC-SAM surface were found to have the ionic solvation nature of the PC head groups. These properties were also compared to those obtained previously for an oligo(ethylene glycol) (OEG) SAM system and bulk water.
进行了分子模拟，以研究在存在明确的水分子和离子的情况下，蛋白质（溶菌酶，LYZ）与磷酸胆碱封端的自组装单分子层（PC-SAMs）之间的相互作用。结果表明，当蛋白质接近PC-SAM表面时，PC-SAM表面上方的水分子会对蛋白质产生强大的排斥力。分析了PC-SAM表面上方水分子的结构和动力学性质，以提供有关水合作用在表面对蛋白质吸附的抗性中所起作用的信息。从停留时间动力学可以看出，与本体水相比，PC-SAM表面正上方的水分子明显减速，这表明PC-SAM表面在其头部基团周围产生了一层紧密结合的结构化水层。此外，发现PC-SAM表面附近界面水分子的取向分布和重新取向动力学具有PC头部基团的离子溶剂化性质。还将这些性质与先前在聚（乙二醇）（OEG）SAM系统和本体水中获得的性质进行了比较。
