基于新型共轭聚电解质-贵金属纳米复合体系的荧光生化传感研究

In this project, a series of novel conjugated polyelectrolytes containing different π-conjugated backbones and charged side chains (including carboxylate, sulfonate, quaternary ammonium salt) in their architectures will be designed and synthesized. Thus novel nanocomposite materials can be constructed with these new conjugated polyelectrolytes and noble metal nanoparticles (silver, gold and palladium,etc) by electrostatic interactions or in-situ reactions, which is vital and promising to develop novel sensor technologies.They will be used in fluorescent sensing systems for sensitive and selective detection of ions,biomolecules and cells in environmental and vital system by means of FRET (fluorescence resonance energy transfer), IFE (inner-filter effect) or other modes.These sensors will not only offer the optoelectronic advantages of conjugated polymers (such as strong fluorescence and signal amplification) and water solubility of electrolytes, but also provide properties of noble metal nanomaterials, which can efficiently eliminate the variable and ambiguous interference from light intensity, probe concentration, environmental conditions and instrumental efficiency, etc. Therefore, a technology platform based on these new nanocomposites and sensing modes will be established to sensitively and selectively obtain quantitative chemical and biological information in complex system, and which will expand the application of composite systems of conjugated polyelectrolytes and noble metal materials in disease diagnosis, genes mutations, environmental detection and national security.

本项目拟设计合成系列含有不同主链及側链（包括羧酸根、磺酸根、季铵盐等）的新型荧光共轭聚电解质。探索这些新型共轭聚电解质与贵金属（金、银、钯等）纳米材料经过电荷作用或原位合成形成复合体系，通过FRET、内滤效应等多种作用模式产生荧光信号变化的机制，发展基于新型纳米复合材料的传感技术，实现对环境和生命体系中多种离子、生物分子和细胞的检测。这类新型复合体系不仅拥有共轭聚合物优异的光电性质（如强的荧光和信号放大）和电解质的水溶性，而且拥有贵金属纳米材料的特征性,能有效地克服单一体系的荧光易受激发光强度、探针浓度、微环境和检测效率等众多可变或难以定量因素的干扰，从而实现在复杂体系（如生物体）中高灵敏、高选择性地准确获取化学与生物定量信息，为共轭聚电解质与贵金属材料的复合体系在医疗诊断、基因突变观测、环境检测以及国家安全防御等方面的应用提供新的物质基础和传感模式。

本项目以发展应用于环境和生命体系中多种离子、生物分子和细胞的快速、准确、高灵敏、高选择性检测的新型荧光生化传感体系为目标，成功地制备了一系列新型含阴离子侧链（磺酸侧链）的聚苯乙炔-吡啶类、含阳离子侧链（季铵基）的聚芴-吡啶类共轭聚电解质。系统研究了具有不同结构、形貌、尺寸及化学修饰的贵金属（金、银等）纳米（粒子、棒、片、线）与含有特定结构的新型共轭聚电解质通过静电作用或原位组装形成纳米复合体系。研究了新型纳米复合传感体系的荧光发射、电子传导和选择性分子识别能力，构建了基于新型的共轭聚电解质-贵金属纳米复合传感体系为敏感载体的高灵敏、高选择性的碘负离子、三聚氰胺、依替米星、过硫酸根离子、精氨酸、植酸、肝素、鱼精蛋白等荧光化学生物传感器。提高了复杂体系中荧光传感器的灵敏度、稳定性和抗漂白能力。纳米材料-聚合物复合体系可以为设计具有优越化学生物传感性能的新型材料提供一个巨大的空间和平台。另外,我们还拓展研究了双芘席夫碱衍生物-银纳米复合探针、新型小尺寸聚苯乙炔-吡啶类共轭聚电解质量子点及小尺寸含芘-吡啶基团的共轭聚合物纳米棒的优异传感及成像性能。本项目到目前为止已在 Talanta等期刊上发表研究论文 8 篇，申请专利 3项，培养研究生13名。