基于新型荧光共轭聚合物复合体系的设计制备及其在生物检测中的应用研究

Water-soluble fluorescent conjugated polymers have shown promising applications in the fields of cell imaging, biosensing, diagnosis and therapy, due to their superior optical properties. However, luminescent efficiency of water-soluble conjugated polymers for practical applications is required to be further improved. Moreover, electrostatic interaction is commonly used for conjugated polymer to combine with analytes, which is lacking of specific recognition and limits their application in chem- and bio-detection. Metal-enhanced fluorescence phenomenon is referred to the enhancement in fluorescence intensity when a fluorophore is close to the plasmonic nanostructures, which can be used to improve the optical properties of conjugated polymers. In this project, we will design and synthesize a series of water-soluble conjugated polymers with functional modifications, which can specifically capture biomolecules including proteins, DNA, saccharides, even cancer cells and pathogens. Then, a planar sensing platform will be built up based on metal-enhanced fluorescence. By precisely adjusting the distance between the metal substrate and conjugated polymer via binding with biological analytes, highly efficient and selective detection will be achieved by observing the variation in fluorescence signals, which makes it possible to be widely used in bio-detection and early disease diagnosis in the future.

水溶性荧光共轭聚合物因其独特的光学性能，在细胞成像、生物传感和疾病诊断等领域显示出广阔的应用前景。但在实际应用中，水溶性共轭聚合物发光效率仍需进一步提高。此外其与被检测物的结合，主要是通过静电相互作用，因而缺乏特异性识别，一定程度上限制了其在化学和生物检测方面的广泛应用。金属增强荧光效应，主要是指荧光物质靠近金属表面时，受表面等离子体共振影响，荧光强度大幅增加的现象。该效应可为改善共轭聚合物的发光性能提供新的思路。本项目中我们将设计和合成具有特异性识别作用的新型水溶性荧光共轭聚合物，使其能特异性捕获生物分子。在此基础上制备平面薄膜检测体系，在纳米尺度上精确调控金属基底和共轭聚合物之间的作用距离，利用金属增强荧光效应等机制观察荧光共轭聚合物光学信号的变化，实现对蛋白质、核酸和糖类等生物分子乃至肿瘤细胞和病原菌的便捷、精准和高效识别，使之将来在生物检测和疾病早期诊断领域的实际应用成为可能。

水溶性荧光共轭聚合物材料由于其独特的光学性能，在化学和生物检测领域具有广阔的实际应用前景。在实际应用中，仍需提高荧光共轭聚合物材料的发光效能，以及其与不同检测物的识别能力。本项目设计合成了具有不同识别功能的水溶性荧光共轭聚合物。通过荧光共轭聚合物材料与生物分子之间不同种类的分子间作用力，可以与生物分子发生特异性结合，并可以快速高效的识别多种生物分子。利用贵金属表面等离子体共振效应，将共轭聚合物与贵金属纳米材料有效复合。设计制备出了新型荧光聚合物纳米复合材料检测体系，有效的提高了荧光共轭聚合物材料的荧光发射效率，并深入研究了该体系中贵金属纳米材料对共轭聚合物荧光发射性能的影响。利用构建的荧光复合物材料检测体系，系统深入的研究了荧光共轭聚合物如何特异性结合生物分子，以及结合前后光学信号的变化规律，实现了对生物分子乃至部分肿瘤细胞、病原微生物等的高效精准的识别检测。本项目所设计制备的新型荧光复合材料体系，在生物检测和疾病诊断领域具有实际的应用价值。