基于异质二聚体的近红外激活式适配体传感体系在微囊藻毒素LR检测中的应用研究

Heterodimers with excellent performance, which would make up for the deficiency of homogeneous nanomaterials and be endowed with two different functions to single particles, have become one of the hot research topics in the field of nanotechnology and analytical chemistry. Because of its strong hepatotoxicity and difficulty to be degraded, the determination of microcystis-LR with (MC-LR) in water and aquatic products is of great significance. This project aims to construct an NIR-activated sensing platform based on heterodimers composed of lanthanide-doped upconversion nanoparticles and metal-organic frameworks (UCNPs-MOFs) for the detection of MC-LR specifically. The sensing platform consists of a UV light-activated aptamer probe and this kind of heterodimers, in which UCNPs act as the nanotransducers to operate the platform in response to NIR light and MOFs as the region of loading aptamer probes. In the presence of the targets, they would interact with the aptamer, accompanied by fluorescence enhancement, which can be used to recognize the targets specifically. Meanwhile, the construction and detection mechanism of the sensor platforms will be investigated through the physicochemical methods. This proposed project will not only enrich the synthesis methods and practical applications of heterodimers, but also provide novel means for the detection of food contaminants, laying the foundation for the development of reagent kit.

赋予单一粒子两种不同功能的异质二聚体，是纳米科学和分析化学领域的前沿热点之一。微囊藻毒素LR（MC-LR）具有强烈的肝毒性且性质稳定，其在水体及水产品中的含量测定对于保障饮水及食品安全具有重要的现实意义。本项目拟首次利用上转换纳米粒子/金属-有机骨架材料（UCNPs/MOFs）异质二聚体构建近红外光激活式传感体系，实现MC-LR可控时间的特异性检测。该体系由此二聚体与光激活式适配体（aptamer）探针构成，其中UCNPs可吸收红外光，发射引发该传感器响应的紫外光，而MOFs作为负载aptamer探针的区域，在加入靶标后，可引起染料修饰探针的荧光变化，由此构建荧光增强型传感体系，实现对靶标的识别与灵敏检测。此外，拟借助光谱学、热力学、理论计算等手段，系统阐明传感体系的构建机理和识别机制，优化检测性能。该项目既能丰富异质二聚体的合成方法、机理和应用，又可以为污染物的检测提供新颖的手段。

上转换纳米粒子具有独特的荧光性质，是纳米材料和分析化学领域的前沿热点之一。金属有机骨架MOF 材料的研究更是引人关注。将两者结合，开发性能优异的纳米材料，提升上转换纳米粒子的传感应用能力，促进荧光纳米材料领域的发展，具有重要的研究意义和应用价值。在本项目中，我们合成了一系列具有不同发光性质的上转换纳米粒子、不同系列的MOF材料，以及UCNPs/MOF异质二聚体，探索了不同反应条件对合成材料的影响，并基于这些合成材料开发了一系列荧光增强型传感器检测微囊藻毒素MC-LR，并阐明了传感体系的检测机制。此外进一步扩展稀土基纳米传感范围，并开发MOF等材料的光热及纳米酶性质，构建了一系列纳米传感体系。具体包括：基于稀土上转换发光特点及紫外光敏键，设计近红外光激活式适配体，构建了时空可控的荧光增强型微囊藻毒素LR检测体系；基于稀土上转换纳米粒子的优点与适配体的选择性，结合二维纳米材料或磁球等，构建了荧光传感体系用于环境雌激素、微囊藻毒素的l灵敏检测；基于MOF等新型纳米材料，构建酶联免疫信号放大平台，发展双信号传感体系用于微囊藻毒素、环境雌激素的检测；基于稀土配合物发光，构建了吡啶二羧酸传感器，并结合线性回归分析法，实现了多种金属离子的区分与检测。本项目既能丰富上转换纳米粒子/MOF材料的合成方法和实际应用，又可以为拓展微囊藻毒素等食品污染物的实时检测提供理论和技术支持。