基于金纳米颗粒表面静电-疏水协同作用的糖脂类化合物荧光传感研究

In this project, the synergy of electrostatic and hydrophobic interactions on the surface of gold nanoparticles (Au NPs) will be explored and exploited for the construction of hybrid sensors for lipopolysaccharide determination. The hybrid sensors developed here consist of Au NPs and surface assembled fluorescent probes. To tune and optimize the affinity and specificity of the binding between fluorescent probes and Au NPs, the synergy of non-covalent interactions on the surface of Au NPs will be systematically manipulated through tuning the electrostatic or hydrophobic properties of fluorescent probes and/or the surface properties of Au NPs. One of the key tasks in this project is to develop quantitative models for the exploration of surface-related cooperative binding interactions, a model which will greatly benefits the development of Au NPs-based hybrid sensing systems. Moreover, we will explore the principle of this kind of sensing systems, which exploits a competition of non-covalent binding onto the surface of Au NPs between fluorescence probes and analytes. New routes to improve the selectivity and sensitivity for sensing will also be explored. Finally, these Au NPs-based hybrid sensors will be used for the fluorescent turn-on sensing of endotoxin (as a model of lipopolysaccharide), which is a major component in the outer membranes of Gram-negative bacteria, and contributes greatly to the structural integrity of the bacteria. These studies, not only exploring the principle of synergy of non-covalent interactions, but also developing sensitive and selective sensing systems, will greatly drive the development of the design of novel optical sensing systems and their applications.

构建并制备一系列具有不同静电-疏水作用的复合金纳米颗粒荧光传感体系，进行糖脂类化合物的荧光传感研究。通过改变传感体系疏水链的长度和结构，调控其疏水作用能力强弱，通过改变端基带电基团，调控其电荷性质和数量，以此来调控传感体系静电-疏水协同作用的能力和特异性，集中研究其静电-疏水协同作用机制和作用原理，建立协同作用量化模型，探索此类特异、灵敏的复合金纳米颗粒荧光传感体系设计的基础理论和实践模式，并探讨基于竞争协同作用的传感机制。应用于以内毒素为典型的糖脂类生物活性分子的特异、灵敏荧光检测，同时为其它类型的生物分子协同传感体系的建立提供理论依据和实践指导，推动光学传感机理、原理、探针设计以及应用研究的发展。

构建并制备了一系列具有不同静电-疏水作用的复合金纳米颗粒荧光传感体系，进行糖脂类化合物的荧光传感研究。合成了4种不同静电/疏水性质的荧光体以及两种不同静电性质的金纳米颗粒，通过改变疏水链的长度和结构，调控其疏水作用能力强弱，通过改变端基带电基团，调控其电荷性质和数量，以此来调控传感体系静电-疏水协同作用的能力和特异性；系统地调控了金纳米颗粒的表面配体组成，考察了它们与4种不同脂质体之间的相互作用，认为在AuNPs与脂质体的吸附与相互作用中，配体的大尺寸性质较之芳香性质有着更为重要的作用；该纳米体系可应用于以内毒素为典型的糖脂类生物活性分子的特异、灵敏荧光检测，同时为其它类型的生物分子协同传感体系的建立提供了理论依据和实践指导，推动光学传感机理、原理、探针设计以及应用研究的发展。