“Turn-on”型荧光能量共振转移侧流层析淬灭效率机制的研究及检测体系的构建

在小分子化合物检测中，“Turn-on”模式荧光淬灭型能量共振转移侧流层析免疫分析与传统“Turn-off”竞争模式侧流层析免疫分析不同，检测信号随化合物浓度增加而增强，提高了检测的灵敏度。而荧光淬灭效率是影响整个反应体系灵敏度的关键因素，它主要与荧光供体/受体选择及供体/受体之间的距离有关。量子点、荧光微球及上转换纳米材料具有特殊光学性质，是荧光供体的备选材料；在申请者最近研究中，制备的不定形碳纳米粒子具有较强淬灭荧光的性能，是受体选择理想材料；通过对比分析研究，优化荧光淬灭效率最高的组合，是提高灵敏度的关键。单克隆抗体、抗体Fab片段及单链抗体识别能力相同，但它们尺寸不同，这将影响供体/受体之间的距离，进而影响淬灭效率。因此，申请者拟从这两大方面阐明影响荧光淬灭效率的机制，构建高灵敏度“Turn-on”模式荧光淬灭型能量共振转移侧流层析免疫分析体系，为小分子化合物检测提供新型检测模式。

In small molecules on-site testing, “Turn-on” mode fluorescence-quenching based resonance energy transfer lateral flow immunoassay (FRET-LFA) is quite different from the conventional “Turn-off” competition mode lateral flow immunoassay. The detection signals intensity is proportion to the target concentration, which will improve the sensitivity obviously. The key factor to the sensitivity of the assay system is the fluorescence-quenching efficiency that is mainly related to the selection of different donor/acceptor pairs and their distance. Quantum dots, fluorescent microspheres and upconversion nanoparticles have special optical properties, which can be used as fluorescent donors. The amorphous carbon nanoparticles (ACNPs) have a strong fluorescence quenching property, which is an ideal acceptor. Through comparative analysis, optimizing the combination of the highest fluorescence quenching efficiency is the key to improving sensitivity. Monoclonal antibody, Fab fragment and single chain antibody fragment have the same affinity, but their sizes are different which will alter the distance of the donor/acceptor and further influence the quenching efficiency. Thus, the aim of the study is to clarify the quenching efficiency from the two aspects and establish “Turn-on” mode FRET-LFA system for the analysis of small molecules, which will provide novel on-site testing tool for small molecules.