Shen Xiaoyue, Liu Rujia, Wang Dengchao
School of Chemical Sciences, University of Chinese Academy of Sciences, Beijing 100049, P. R. China.
J Phys Chem Lett. 2023 Oct 5;14(39):8805-8810. doi: 10.1021/acs.jpclett.3c02359. Epub 2023 Sep 25.
Conductive nanopipettes have been recognized as powerful multifunctional platforms for electrochemical sensing applications in confined spaces. However, the electron-transfer processes of many biological analytes (i.e., enzymes or proteins) are slow and coupled with chemical reactions, which have not been well elucidated in conductive nanopipettes. In this Letter, both experimental and simulation methods are used to study electron-transfer processes coupled to chemical reactions (EC mechanism) in carbon nanopipettes (CNPs). It is demonstrated that the electroactive species can serve as redox mediator to help oxidize and reduce the nonelectroactive analytes of interest in the solution and produce noticeable catalytic current signals. Besides, glutathione was directly measured by using ferrocenemethanol as the redox mediator in the CNPs. The elucidated EC processes in CNPs would offer a new opportunity to measure nonelectroactive analytes in biological fields.
导电纳米移液器已被公认为是用于受限空间内电化学传感应用的强大多功能平台。然而，许多生物分析物（即酶或蛋白质）的电子转移过程缓慢且与化学反应耦合，在导电纳米移液器中尚未得到很好的阐明。在本信函中，实验和模拟方法均被用于研究碳纳米移液器（CNP）中与化学反应耦合的电子转移过程（EC机制）。结果表明，电活性物质可作为氧化还原介质，帮助氧化和还原溶液中感兴趣的非电活性分析物，并产生明显的催化电流信号。此外，在碳纳米移液器中使用二茂铁甲醇作为氧化还原介质直接测定了谷胱甘肽。碳纳米移液器中阐明的EC过程将为生物领域中测量非电活性分析物提供新的机会。
