Li Hongkun, Cai Qianqian, Li Pingping, Jie Guifen
Key Laboratory of Optic-Electric Sensing and Analytical Chemistry for Life Science, MOE, College of Chemistry and Molecular Engineering, Qingdao University of Science and Technology, Qingdao 266042, P. R. China.
Anal Chem. 2024 Aug 14. doi: 10.1021/acs.analchem.4c02782.
In this work, the relationship between electrochemiluminescence (ECL) signal and driving voltage was first studied by self-made reduced and oxidized closed bipolar electrodes (CBPEs). It was found that when the driving voltage was large enough, the maximum ECL signals for the two kinds of CBPEs were the same but their required drive voltages were different. Zinc cobalt nitrogen doped carbon material (ZnCoN-C) had an outstanding electric double layer (EDL) property and conductivity. Therefore, it could significantly reduce the driving voltage of two kinds of CBPE systems, reaching the maximum ECL signal of Ru(bpy). Interestingly, when the ZnCoN-C modified electrode reached the maximum ECL signal, the bare electrode signal was zero. As a proof-of-concept application, a zero-background dual-mode CBPE-ECL biosensor was constructed for the ultrasensitive detection of ochratoxin A (OTA) in beer. Considering that beer samples contained a large number of reducing substances, a reduced CBPE system was selected to build the biosensor. Furthermore, a convenient ECL imaging platform using a smartphone was built for the detection of OTA. This work used a unique EDL material ZnCoN-C to regulate the driving voltage of CBPE for the first time; thus, a novel zero-background ECL sensor was constructed. Further, this work provided a deeper understanding of the CBPE-ECL system and opened a new door for zero-background detection.
在本工作中，首次通过自制的还原态和氧化态封闭双极电极（CBPEs）研究了电化学发光（ECL）信号与驱动电压之间的关系。研究发现，当驱动电压足够大时，两种CBPEs的最大ECL信号相同，但所需的驱动电压不同。锌钴氮掺杂碳材料（ZnCoN-C）具有优异的双电层（EDL）性能和导电性。因此，它可以显著降低两种CBPE系统的驱动电压，达到Ru(bpy)的最大ECL信号。有趣的是，当ZnCoN-C修饰电极达到最大ECL信号时，裸电极信号为零。作为概念验证应用，构建了一种零背景双模式CBPE-ECL生物传感器，用于超灵敏检测啤酒中的赭曲霉毒素A（OTA）。考虑到啤酒样品中含有大量还原物质，选择还原态CBPE系统构建生物传感器。此外，还构建了一个使用智能手机的便捷ECL成像平台用于OTA的检测。本工作首次使用独特的EDL材料ZnCoN-C调节CBPE的驱动电压；因此，构建了一种新型零背景ECL传感器。此外，本工作为CBPE-ECL系统提供了更深入的理解，并为零背景检测打开了一扇新的大门。
