Institute of Modern Physics, Chinese Academy of Sciences , Lanzhou 730000 , China.
University of Chinese Academy of Sciences , Beijing 100049 , China.
ACS Appl Mater Interfaces. 2019 Oct 16;11(41):38055-38060. doi: 10.1021/acsami.9b13088. Epub 2019 Oct 7.
Rectified ion transport in nanochannels is the basis of ion channels in biological cells and has inspired emerging nanochannel applications in ion separation, Coulter counters, and biomolecule detection and nanochannel energy harvesters. In this work we fabricated a polyethylene terephthalate (PET) conical nanochannel using latent ion track etching technique and then systematically studied the ion transport and influence of cation species on the nanochannel surface with cyclic - measurement. We discovered the electrical regulation of the reversible and irreversible modification of the nanochannel transportation by bivalent and trivalent cations, revealing the existence of the switching threshold voltage which can control the current rectification in bivalent solution. The proposed mechanism of the transport state transition in the PET nanochannel mimics behaviors of voltage-gated biological ion channels. These findings provide new insight into the understanding of the ion channel signaling and translocation control of charged particles in nanochannel applications.
纳米通道中的离子整流传输是生物细胞离子通道的基础，这启发了新兴的纳米通道应用，如离子分离、库尔特计数器、生物分子检测和纳米通道能量收集器。在这项工作中，我们使用潜伏离子轨迹蚀刻技术制造了一个聚对苯二甲酸乙二醇酯（PET）锥形纳米通道，然后通过循环测量系统地研究了离子传输以及阳离子种类对纳米通道表面的影响。我们发现了二价和三价阳离子对纳米通道传输的可逆和不可逆修饰的电调节，揭示了存在开关阈值电压，可以控制二价溶液中的电流整流。在 PET 纳米通道中，传输状态转变的提出机制模拟了电压门控生物离子通道的行为。这些发现为理解纳米通道应用中带电粒子的离子通道信号和转位控制提供了新的见解。
