Hydrophilic Macroionic Solutions - the Roles of Counterions, Co-ions and Surface Water Layers

亲水性大离子溶液 - 抗衡离子、共离子和表面水层的作用

• 批准号: 1607138
• 负责人: Tianbo Liu
• 金额: $ 42万
• 依托单位: University of Akron
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2016
• 资助国家: 美国
• 起止时间: 2016-09-15 至 2020-08-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1607138&HistoricalAwards=false
• 关键词: Hydrophilic; Macroionic; Solutions; Roles; Counterions

In this project funded by the Macromolecular, Supramolecular and Nanochemistry Program of the Chemistry Division, Professor Tianbo Liu of the University of Akron explores the solution properties of macroions. These macroions are between 1 and 10 nanometers (nm) in size and represent a missing link between simple ions and large colloids. The project aims to explore the microscopic features of macroions and their interactions with local environments, that is, the counterions, the co-ions, and the layered structures they make in water. These interactions are being explored in order to unveil the fundamental reasons behind the unique solution properties of the macroions such as their self-assembly into blackberry-like structures. The blackberry formation process is found to mimic the virus capsid formation process. This research could have broad impacts on other fields, such as physical chemistry, supramolecular chemistry, biochemistry, materials sciences and nanotechnology. The project involves training graduate and undergraduate students, and encouraging high school students to participate in national science competitions and scientific careers. The research infrastructure is being enhanced through scientific collaborations.The research has three complementary components. First, the macroion-counterion interaction is being characterized by determining the radial distributions of counterions around macroions and the stability of the macroions in the presence of an excess number of counterions. Secondly, the effect of co-ions on the macroions are being examined, particularly for the preferential interactions between chiral macroions and chiral co-ions. Third, the detailed changes of surface water structures of both counterions and macroions during their interaction are being studied. Relatively simple models, mainly polyoxometalate clusters and metal-organic nanocages, are employed for the study. The solution studies employ a combination of techniques, such as static and dynamic laser light scattering, synchrotron small-angle X-ray scattering, isothermal titration, nuclear magnetic resonance, electron microscopy, and Zeta potential analysis. The conclusions are expected to be universal and may be instructive for understanding more complex systems such as polyelectrolyte and biomacromolecular solutions.

在这个由化学系大分子，超分子和纳米化学项目资助的项目中，阿克伦大学的Tianbo Liu教授探索了大离子的溶液性质。这些大离子的大小在1到10纳米（nm）之间，代表了简单离子和大胶体之间的缺失环节。该项目旨在探索大离子的微观特征及其与局部环境的相互作用，即反离子，共离子以及它们在水中形成的分层结构。这些相互作用正在探索，以揭示背后的大离子，如他们的自组装成黑莓状结构的独特的解决方案的性质的根本原因。黑莓的形成过程被发现模仿病毒衣壳的形成过程。 这项研究可能会对其他领域产生广泛的影响，如物理化学，超分子化学，生物化学，材料科学和纳米技术。该项目涉及培训研究生和本科生，并鼓励高中生参加全国科学竞赛和科学事业。通过科学合作加强了研究基础设施，研究有三个相辅相成的组成部分。首先，通过确定反离子在大离子周围的径向分布和在存在过量反离子的情况下大离子的稳定性来表征大离子-反离子相互作用。其次，研究了共离子对大离子的影响，特别是手性大离子和手性共离子之间的优先相互作用。第三，研究了反离子和大离子相互作用过程中表面水结构的详细变化。相对简单的模型，主要是聚氧乙烯簇和金属有机纳米笼，用于研究。溶液研究采用了静态和动态激光散射、同步加速器小角X射线散射、等温滴定、核磁共振、电子显微镜和Zeta电位分析等技术的组合。所得结论具有普遍性，对理解更复杂的体系如水溶液和生物大分子溶液具有指导意义。