甜菜碱两性聚电解质的界面行为研究

It is important to study the interfacial behavior of polyzwitterion because the studies will be helpful for understanding the theory of conformational change of polyzwitterion. Besides, the studies are also helpful for developing new types of polyzwitterionic interfacial materials. So far, the relationship between the conformational behavior of polyzwitterion and the interfacial properties remains unclear. The critical step to solve this problem is the accurate characterization of conformational behavior at interfaces. In the present project, we will choose polybetaine as a typical system to study its interfacial behavior. We will control the hydrophilicity/hydrophobicity of the main chain and the chemical structure of the side group to prepare a series of polybetaines with novel structures and properties. By use of the combination of quartz crystal microbalance with ellipsometer and surface plasmon resonance, we will systematically investigate the interfacial conformational behavior of polybetaines under various external conditions. We will focus on the influences of inter-/intrachain interactions on the conformational change. After well understanding the above mentioned interfacial conformational behavior of polybetaines, we will study the controllable adsorption of proteins and adhesion of cells on the polybetaine surfaces to clarify the relationship between the conformational behavior and the interfacial properties. The implementation of this project will help us to understand the conformational change of polyzwitterion and the relationship between the conformational behavior and the interfacial properties of polyzwitterion. This project could also be useful for developing new types of polyzwitterion based interfacial materials.

研究两性聚电解质的界面行为，对于了解两性聚电解质构象变化规律，发展两性聚电解质基界面材料有重要意义。目前，对两性聚电解质构象行为与其界面性质间的关系仍缺乏足够了解，解决该问题的关键是对其界面构象行为进行精确表征。本项目拟以甜菜碱两性聚电解质为研究对象，对其主链亲/疏水性及侧基化学结构进行控制，以制备结构不同、性质各异的一系列甜菜碱两性聚电解质。利用石英晶体微天平-椭偏仪联用系统、表面等离子体共振仪等表征手段对表面接枝甜菜碱两性聚电解质在不同外界环境下的构象行为进行系统研究，重点探讨各种链间/内相互作用对其构象变化的影响。在此基础上，进一步研究蛋白质、细胞等生物体在其表面的可控吸附或粘附,逐步厘清其构象行为与界面性质间的关系。本项目的实施，将加深我们对两性聚电解质构象变化规律的理解，提升我们对其构象行为与界面性质间关系的认识，为发展具有新型特性的两性聚电解质基界面材料提供研究思路和实验依据。

研究甜菜碱两性聚电解质的界面行为，对于了解两性聚电解质构象变化规律，发展两性聚电解质基界面材料有重要意义。由于对两性聚电解质构象行为与其界面性质间的关系缺乏足够了解，需要对两性聚电解质的界面构象行为进行精确表征。本项目中，申请人利用石英晶体微天平-椭偏仪联用系统、接触角测量仪等表征手段对表面接枝聚电解质在不同外界环境下的构象行为进行了系统研究，并在此基础上研究了固-液界面甜菜碱两性聚电解质、蛋白质表面接枝甜菜碱两性聚电解质以及电极表面甜菜碱两性聚电解质的各种行为与性质。通过对甜菜碱两性聚电解质侧基化学结构、溶液中离子浓度以及离子种类进行控制，重点探讨了各种链间/内相互作用以及离子-链间相互作用对甜菜碱两性聚电解质构象变化和界面性质的影响。申请人还研究了蛋白质在甜菜碱两性聚电解质表面的吸附，并通过离子种类对其进行调控，进一步厘清了两性聚电解质构象行为与界面性质间的关系。通过该项目的实施，申请人回答了链间/内以及离子-链间相互作用如何影响甜菜碱两性聚电解质界面行为这一科学问题，提升了我们对甜菜碱两性聚电解质构象行为与其界面性质间关系的认识，为发展新型两性聚电解质基高分子材料提供了研究思路。