油滴-水界面植物多酚与表面活性剂分子膜的缔合行为及性质调控

The knowledge of molecular interaction and function control at oil-water interface has important values for the foundamental science as well as many industrial applications. This project will study the aggregation of surfactant molecules and the microstructural and interfacial properties of surfactant molecular film at oil-water interface, with the aim of understanding of the formation mechanism of surfactant molecular film at oil-water interface in surfactant emulsion. Through the investigation of the association of plant polyphenol curcuminoids in surfactant molecular film at oil-water interface, the interaction force, location, constant value, partition coefficient and their relationships with the microstructural and interfacial properties of surfactant molecular film will be obtained. The thermodynamic parameters including dissociation equilibrium constant, degree of ionization, and the change of Gibbs Free Energy of polyphenol hydrolysis at basic conditions in surfactant emulsion will be determined. The relationship between polyphenol hydrolysis and the microstructual and interfacial properties of surfactant molecular film will be discussed. The kinetics of polyphenol degradation in surfactant emulsion will be studied in terms of the kinetic parameters including order, constant, and half-life of polyphenol degradation. We will also study the radical scavenging activity of polyphenols in surfactant emulsion. The new approach of the changes of the microstructural and interfacial properties of surfactant molecular film will be further developed to improve the stability and bioavailability of polyphenols.

油滴-水界面分子相互作用及性质调控，在基础研究和实际应用方面都具有重要意义。本项目从研究表面活性剂乳液油滴-水界面表面活性剂分子的聚集行为出发，通过研究表面活性剂分子膜的精细结构和界面性质，阐明表面活性剂分子膜的生成机理；以具有重要药理活性的姜黄素类植物多酚为模型药物分子，重点变化其有效活性基团酚羟基的数量和位置，采用实验和计算机模拟相结合的方法考察植物多酚与表面活性剂分子膜缔合过程中疏水、氢键等弱相互作用之间的协同或制约关系，确定植物多酚的缔合位置、缔合常数及油水分配系数，阐明植物多酚与表面活性剂分子膜的缔合机理；进一步考察表面活性剂分子膜缔合的植物多酚的碱性水解平衡常数、解离度、自由能等热力学参数以及降解反应级数、速率常数、半衰期等动力学参数，并且研究植物多酚自由基抑制性能，建立通过调控表面活性剂分子膜精细结构和界面性质的新途径来提高植物多酚的稳定性和药理活性。

基于被称为“第三代抗癌化学预防药”的姜黄素植物多酚的包载性质及包载机理研究，对于推动天然植物多酚的高效保健及临床应用都具有重要意义。本项目从研究吐温类表面活性剂在界面和溶液中的聚集行为出发，通过研究表面活性剂聚集体的微观结构和界面性质，考察了姜黄素植物多酚对表面活性剂聚集体结构的影响规律，发现姜黄素植物多酚对表面活性剂聚集体的生成与表面活性剂的烷基链长度和不饱和度有密切关系；使用表面活性剂胶束、囊泡等聚集体对姜黄素植物多酚进行包载，获得了姜黄素植物多酚的稳定性和自由基清除能力等热力学及动力学数据；并通过多种方法研究了姜黄素植物多酚的缔合作用力、缔合位置及缔合常数，阐明了姜黄素植物多酚与表面活性剂聚集体的相互作用机制。进一步拓展研究了蛋白质纳米颗粒对姜黄素植物多酚的包载性质和包载机理。.通过本项目研究，发表了学术期刊学术论文10篇，有16名研究生和25名本科生参加了研究工作，8名研究生和16名本科生获得学位。