Wu Zeng-Qiang, Li Cheng-Yong, Ding Xin-Lei, Li Zhong-Qiu, Xia Xing-Hua
State Key Laboratory of Analytical Chemistry for Life Science, School of Chemistry and Chemical Engineering, Nanjing University, Nanjing 210023, China.
School of Public Health, Nantong University, Nantong 226019, China.
J Phys Chem Lett. 2022 Jun 8:5267-5274. doi: 10.1021/acs.jpclett.2c01166.
Ion transport in nanochannels of a size comparable to that of hydrated ions exhibits unique properties due to the synergistic effect of various forces. Here, we design a nanochannel/ion channel composite (NIC) membrane that shows a high ion current rectification (ICR) ratio in different electrolytes. Experimental and theoretical results demonstrate that the synergistic effect of electrostatic interaction and ionic dehydration plays an important role in regulating the ICR behavior of the NIC membrane. We find that electrostatic attraction between ions and the channel surface in the ultraconfined space increases the probability of ionic dehydarion, resulting in different dehydration energy costs for different ions. This further alters the driving force for ion transport and thus regulates ICR of the NIC membrane. This work provides fundamental knowledge of ion transport in ion channels, which aids in the understanding of the function of biological systems and the design of high-performance nanochannel devices.
尺寸与水合离子相当的纳米通道中的离子传输，由于各种力的协同作用而呈现出独特的性质。在此，我们设计了一种纳米通道/离子通道复合（NIC）膜，该膜在不同电解质中表现出高离子电流整流（ICR）比。实验和理论结果表明，静电相互作用和离子脱水的协同效应在调节NIC膜的ICR行为中起重要作用。我们发现，在超受限空间中离子与通道表面之间的静电吸引增加了离子脱水的概率，导致不同离子具有不同的脱水能量成本。这进一步改变了离子传输的驱动力，从而调节了NIC膜的ICR。这项工作提供了离子通道中离子传输的基础知识，有助于理解生物系统的功能和设计高性能纳米通道器件。
