Abstract A simple and rapid electrochemical synthesis strategy for in-situ fabrication of toluidine blue (TB)-functionalized metal organic framework (TB@MOFs) thin films via one-step reduction approach was reported. The TB@MOFs thin layer has been synthesized on the working electrode surface in different times at room temperature, and its morphology and thickness was characterized by varied instruments, including scanning electron microscope, transmission electron microscope, and scanning ion conductance microscope. The prepared TB@MOFs shows exceptional electrochemical activity and stability under mild conditions, and its electrochemical response is dependent on the amount of TB molecules which are encapsulated in the MOFs. Based on the TB@MOFs sensing platform, a sensitive label-free electrochemical immunosensor for the detection of Indole-3-acetic acid (IAA, a plant hormone) was developed with a wide linear range (2.5 pg mL−1 - 5 ng mL−1) and a low detection limit (1.4 pg mL−1). Moreover, this immune sensor shows good sensitivity and selectivity in real samples for IAA detection.

中文翻译：

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甲苯胺蓝功能化金属有机骨架薄膜的电化学辅助沉积，用于吲哚-3-乙酸的电化学免疫传感

摘要 报道了一种通过一步还原方法原位制备甲苯胺蓝 (TB) 功能化金属有机骨架 (TB@MOFs) 薄膜的简单快速电化学合成策略。在室温下不同时间在工作电极表面合成了TB@MOFs薄层，并通过扫描电子显微镜、透射电子显微镜和扫描离子电导显微镜等多种仪器对其形貌和厚度进行了表征。制备的 TB@MOFs 在温和条件下表现出优异的电化学活性和稳定性，其电化学响应取决于封装在 MOF 中的 TB 分子的数量。基于TB@MOFs传感平台，开发了一种用于检测吲哚-3-乙酸（IAA，一种植物激素）的灵敏无标记电化学免疫传感器，具有较宽的线性范围（2.5 pg mL-1 - 5 ng mL-1）和低检测限（ 1.4 pg mL-1)。此外，该免疫传感器在用于 IAA 检测的实际样品中显示出良好的灵敏度和选择性。