酚类环境激素电化学传感平台的构建、电催化反应机理的识别及在食品分析中的应用研究

At present, researchers mainly focused on the phenolic environmental hormone in water and silt at home and abroad, and there are few studies on the phenolic environmental hormone in food. Electrochemical biosensors based on nanocomposites have valuable and extensive applications in biological medicine, food science, environmental monitoring and other fields because of its easy operation, high sensitivity, fast response, continuous on-line detection et al. In this work, firstly, noble (transition) metal/g-C3N4 nanocomposites were prepared and a series of electrochemical sensors were constructed. The electrochemical catalytic behaviors of phenolic environmental hormones (such as bisphenol A and diethylstilbestrol) were investigated at different electrochemical sensing platforms. The internal connection among the electrochemical catalytic behaviors of phenolic environmental hormones, chemical composition and configuration (such as size, morphology, specific surface area, crystal surface structure) of catalysts was clarified. The electrochemical catalytic reaction mechanisms of phenolic environmental hormones were further investigated and discussed by different electrochemical techniques, electrochemical-spectrometric hyphenated techniques, rotating ring-disk electrodes and mathematical calculation. At the same time, A series of electrochemical sensors of phenolic environmental hormones with good selectivity, high sensitivity, good reproducibility, low cost, long service life were constructed based on the noble (transition) metal/g-C3N4 nano-composites with excellent physical and chemical properties. A novel method for determination of phenolic environmental hormone residues will be developed in food.

目前，国内外酚类环境激素的研究主要集中在水体、淤泥等环境方面，而对食品中酚类环境激素的研究还很少涉及。而基于纳米复合材料的电化学传感器凭借操作简单、灵敏、快速、易携带、在线等优点，已在生物医药、食品科学、环境检测等领域获得重要且广泛的应用。本研究首先合成贵(过渡)金属掺杂或复合的g-C3N4纳米材料，并构建系列电化学传感器。然后考查双酚A、己烯雌酚等酚类环境激素分子在不同电化学传感平台上的电催化行为，阐明其电催化行为与催化剂的化学组成和结构(如尺寸、形貌、比表面积、晶面等)之间的本质联系。运用各种电化学方法、电化学-光谱联用技术、旋转圆环圆盘电极及量化的计算进一步研究和探讨酚类环境激素的电催化反应机理。同时，利用该纳米复合材料优良的物理、化学特性，构建一系列具有选择性好、灵敏度高、重现性好、成本低、寿命长的酚类环境激素新型无酶电化学传感器，从而建立食品中酚类环境激素残留检测的新方法。

近年来，环境激素对人类的威胁已经引起广泛的关注，无论存在于空气、水还是土壤中，都能强烈地吸附于颗粒上，借助于食物链不断富集，而食品是环境激素进入人体的重要途径，酚作为一类典型的环境激素，广泛存在于食品及食品包装袋中，因此建立一种简单、廉价、高效的食品中酚类环境激素的检测方法是非常重要。本研究合成了一种新型的金纳米-石墨相氮化碳复合纳米材料（AuNPs-g-C3N4），并构建AuNPs-g-C3N4/GCE电化学传感器，考查了双酚A和辛基酚在AuNPs-g-C3N4/GCE上的电催化行为和动力学过程，利用各种电化学方法和量化的计算进一步研究和探讨了双酚A和辛基酚的电催化反应机理。在最佳实验条件下，利用微分脉冲伏安法对双酚A和辛基酚进行检测，其线性范围分别为0.1-6.5 µM和0.1-3.8 µM，检测限分别为0.0176 µM 和0.0324 µM。该传感器表现出较好的稳定性、重现性和抗干扰能力，成功地用于婴幼儿奶粉中双酚A和辛基酚的测定。本研究还发展了ZIF-67C@RGO/NiNPs、ZIF-67C/CuO-NiO、Co3O4/NiNPs、NiCo2O4-AuNPs、MoS2/AuNPs等复合纳米材料并成功构建了亚硝酸盐（NO2-）、葡萄糖（Glu）、过氧化氢（H2O2）、特布他林（TBT）电化学传感平台，并实现了食品样品中NO2-、Glu、H2O2和TBT的灵敏检测。另外，本研究在传感器的构建过程中，合成了一些电化学性能好的双金属氧化物/硫化物复合材料，如NiMn2O4@NiMn2S4、CoMn2O4@CoMn2S4、MnNi2O4@MnNi2S4等，并将这些材料应用于超级电容器的研究。因此本研究在电化学理论上也取得了一定成果。