基于多肽、氨基酸类衍生物手性超分子凝胶的构筑及性能研究

Chiral supramolecular gel is cutting-edge topic in gel materials. It is a significant subject for supramolecular chemistry scientists to understand the transition mechanism of chirality from molecular level to supramolecular level. However, the related theories have not been well developed so far. In this grant, a series of amino acid derivatives and peptide surfactants are designed and synthesized to obtain chiral supramolecular gel in water or mixed solvents, according to the fundamental rules of self-assembly and the characteristics of non-covalent interactions of amphiphilic molecules. Differences of the structures of chiral aggregates among one component, two components and new amphiphiles mixed with traditional surfactants will be investigated. The important roles of hydrogen bonding, π-π stacking and metal coordination in construction of chiral nanostructures will be determined. Finally the inherent correlation of “structure of gelator-non-covalent interactions-chiral aggregates” will be summarized. In addition, the structural transition and chiroptical properties of the chiral supramolecular gel during the dynamic process will be studied into details, which are significant for proposing the formation mechanism of chiral aggregates. The influences of simple physical-chemical conditions on microstructure, chiroptical property and rheological property of gels will be investigated in order to extend their functions and applications. The long-term objective of this research is to provide theoretical support for designing chiral supramolecular gel with specific microstructure and function.

手性超分子凝胶是目前凝胶研究的热点内容，深化认识手性从分子水平向超分子水平的转变机理，获得相关理论是超分子化学家亟待解决的科学问题之一。本项目从自组装角度出发，根据两亲分子间相互作用的特点，设计合成一系列氨基酸衍生物、肽表面活性剂，在水或混合溶剂中构筑手性超分子凝胶。研究单一凝胶因子组分、二元凝胶因子组分、新两亲分子与传统表面活性剂复配体系手性聚集结构的差异。探究氢键、π-π堆积、金属配位作用等在手性自组装体构筑中的作用规律，总结凝胶因子结构-非共价相互作用-手性聚集结构的内在联系。表征手性超分子凝胶形成过程中微观结构和手性光学性质的变化，探究手性结构的形成机理。考察物化条件的改变对凝胶微观结构、手性、流变学性质的影响规律，探索手性超分子凝胶的功能与应用。研究结果将为构筑特定结构与功能的手性超分子凝胶提供实验数据和理论支持。

手性存在于分子、超分子、纳米结构以及宏观结构中，是自然界和生物界的普遍现象。深化认识手性从分子水平向超分子水平的转变机理，获得相关理论是超分子化学家亟待解决的科学问题之一。本项目从自组装角度出发，根据两亲分子间相互作用的特点，设计合成了一系列氨基酸衍生物、肽表面活性剂，在水中构筑手性超分子凝胶。探究了单一凝胶因子组分(多肽)、二元凝胶因子组分（多肽与金属离子、多肽与传统表面活性剂）、手性聚集结构的差异。探究了氢键、金属配位作用等在手性自组装体构筑中的作用规律，总结凝胶因子结构-非共价相互作用-手性聚集结构的内在联系。项目取得的结果包括：1）设计了三种具有不同碱性氨基酸的四肽分子，为开发成本低廉的短肽凝胶因子提供了新的启示；2）比较了单一多肽组分和混合组分（短肽分子与Cu2+、Ag+、Au3+）形成凝胶聚集结构的差异，总结了多肽的二级结构与手性凝胶形成的关系。3）在短肽稳定的铜纳米簇荧光增强方面也取得了一些结果，拓展了多肽的应用范围。三年的深入研究让我们对以上体系的组装规律有了较为全面的了解，对肽分子的自组装结构与功能协同有了新的认识。