基于电化学-光电化学双传感策略的比率型黄曲霉毒素检测研究

As the most toxic mycotoxin contaminants of agricultural products, the high accurate detection of aflatoxins (AF) is important to ensure the safety of agricultural products. Currently, most of the sensors for AF analysis depend on single sensing technology which are incapable of acquiring multi-signals and beset with technological deficiency itself. To improve the detection accuracy by introducing a coupling technology, our project aims to develop the electrochemical (EC) and photoelectrochemical (PEC) dual-mode sensing strategy to construct novel ratiometric aptasensors. First, electroactive molecules labeled aptamers and quantum dots are introduced as probes, and the gold nanoparticles loaded carbon nanofibers (Au/CNFs) prepared controllably is to be used as the supporting materials of aptasensors. The assemble behaviors of probes, especially the uniform assembly of aptamer, on Au/CNFs is to be investigated to construct the sensing interface with high stability and reproduction. The EC and PEC dual-mode sensing strategy is to be developed based on the regulation of electron transfer distance and steric hindrance, and large attention would be paid on the generation and response mechanism of dual signals. Then, ratiometric aptasensors based on the coupling technology of EC and PEC are to be constructed with the expected superior analysis properties, and our proposed strategy should provide a novel way for development of high-performance sensors.

黄曲霉毒素(AF)是当前污染农产品毒性最强的真菌毒素，实现其精准检测对保障农产品质量安全意义重大；现有AF传感器主要基于单一检测方法，难以实现多信号同时获取与方法自身局限性突破。针对AF检测的多技术联用及精准度提高难题，本项目将开展基于电化学(EC)、光电化学(PEC)方法联用的比率型双传感策略研究，首先引入电活性分子标记适配体、量子点作为信号探针，可控制备金纳米粒子负载碳纳米纤维作为传感器基底，分析探针在基底表面的组装行为，重点解决适配体的均匀组装难题，提出高稳定、高可重现性传感界面的构筑策略；之后，结合电位解析原理，发展EC、PEC信号同时获取方法，探讨界面电子传递距离与位阻协同调控的信号响应机制，建立比率型EC-PEC双传感方法；创制基于EC-PEC双传感策略的比率型传感器，实现AFB1、AFB2、AFM1的高灵敏、高精准分析，为我国农产品质量安全评估体系提供新型高效AF检测方法。

黄曲霉毒素（AFs）是当前污染农产品毒性最强的真菌毒素，实现其精准检测对保障农产品质量安全意义重大；现有AFs传感器主要基于单一检测方法，难以实现多信号同时获取与方法自身局限性突破。针对AFs检测的多技术联用及精准度提高难题，本项目开展基于电化学（EC）、光电化学（PEC）联用的比率型双传感方法研究。提出了制备多种高性能敏感材料的新方法，包括NiCo2S4线负载碳纳米纤维可控制备方法、硅量子点（SiQDs）快速制备方法；之后筛选CdTe量子点、亚甲基蓝等为功能探针，发展了基于EC-PEC、电化学-电化学发光（EC-ECL）双方法联用的传感新策略，探讨了界面电子传递与位阻对响应信号的作用机制，解决双传感联用技术对AFs检测精准度提升难题；构筑了系列高性能AFs比率传感器，赋予了传感器可调灵敏度/线性范围、阈值响应以及连续重复使用等多种新功能，为农产品质量安全评估体系提供了AFs高效检测的新途径。在项目资助下，研究人员在Analytical Chemistry、Biosensors and Bioelectronics、Food Chemistry等期刊发表SCI论文19篇，其中IF>6.0的论文15篇；申请中国发明专利4件，其中授权2件。