Zhao Yingjie, Lin Lan, Liu Rujia, Liu Yun, Wang Yue, Wang Dengchao
School of Chemical Sciences, University of Chinese Academy of Sciences, Beijing 100049, P. R. China.
Binzhou Institute of Technology, Weiqiao-UCAS Science and Technology Park, Binzhou 256606, Shandong Province, P. R. China.
Anal Chem. 2024 Mar 12;96(10):4190-4196. doi: 10.1021/acs.analchem.3c05343. Epub 2024 Feb 27.
Dual nanopipettes with two channels have been receiving great attention due to the convenient experimental setup and multiple measuring channels in sensing applications at nanoscale, while the involved dynamic and asymmetrical ion transport processes have not been fully elucidated. In this paper, both experimental and simulation methods are used to investigate the dynamic mass transport processes inside dual nanopipettes with two well-separated channels. The results present that the ion transport resistance through the two channels () is always the add-up of the individual ones ( + ) with respect to the bulk solutions, at various ionic strengths and scan rates. A constant zero-current potential is obtained when loading an asymmetrical electrolyte concentration in the two channels, and the zero-potential current displays a good linear relationship with the bulk concentration outside the pipet. Besides revealing the dynamic and asymmetrical concentration polarization in the dual nanopipettes, these results would also further promote the better usage of dual nanopipettes in electrochemical sensing and imaging applications.
具有两个通道的双纳米吸管因其在纳米尺度传感应用中便捷的实验设置和多个测量通道而备受关注，然而其中涉及的动态和不对称离子传输过程尚未得到充分阐明。本文采用实验和模拟方法来研究具有两个分离良好通道的双纳米吸管内部的动态质量传输过程。结果表明，在各种离子强度和扫描速率下，相对于本体溶液，通过两个通道的离子传输电阻（）始终是各个通道电阻（+）之和。当在两个通道中加载不对称电解质浓度时，可获得恒定的零电流电位，且零电位电流与吸管外部的本体浓度呈现良好的线性关系。这些结果除了揭示双纳米吸管中的动态和不对称浓度极化外，还将进一步促进双纳米吸管在电化学传感和成像应用中的更好使用。
