Pressure Induced Enlargement and Ionic Current Rectification in Symmetric Nanopores

锥形纳米孔的整流特性：小型化的后果

Rectification properties of conically shaped nanopores: consequences of miniaturization

通过数值模拟研究锥形纳米孔长度对离子电流整流特性的影响，发现缩短长度会降低整流能力，但可通过调控表面电荷和窄口形状增强短孔的整流性能。

The effect of the charge pattern on the applicability of a nanopore as a sensor

We investigate a model nanopore sensor that is able to detect analyte ions that are present in the electrolyte solution in very small concentrations. The nanopore selectively binds the analyte ions with which the local concentrations of the ions of the background electrolyte (KCl), and, thus, the ionic current flowing through the pore is changed. Analyte concentration can be determined from calibration curves. In our previous study (Mádai et al. J. Chem. Phys., 147(24):244702, 2017.), we proposed a symmetric model (surface charge is negative all along the pore). The mechanism of sensing was a …

α-溶血素的电流整流与离子选择性：粗粒化分子动力学模拟

Current rectification and ionic selectivity of alpha-hemolysin: Coarse-Grained Molecular Dynamics simulations

本研究利用MARTINI粗粒化分子动力学模拟α-溶血素纳米孔的离子输运，验证了电流不对称与阴离子选择性，并识别出关键带电氨基酸，提出微观解释。

Beyond the Tradeoff: Dynamic Selectivity in Ionic Transport and Current Selectivity

Traditionally, ion-selectivity in nanopores and nanoporous membranes is understood to be a consequence of Debye overlap, in which the Debye screening length is comparable to the nanopore radius somewhere along the length of the nanopore(s). This criterion sets a significant limitation on the size of ion-selective nanopores, as the Debye length is on the order of 1 - 10 nm for typical ionic concentrations. However, the analytical results we present here demonstrate that surface conductance generates a dynamical selectivity in ion transport, and this selectivity is controlled by so-called Dukhin…

Directed motion emerging from two coupled random processes: Translocation of a chain through a membrane nanopore driven by binding proteins

We investigate the translocation of a stiff polymer consisting of M monomers through a nanopore in a membrane, in the presence of binding particles (chaperones) that bind onto the polymer, and partially prevent backsliding of the polymer through the pore. The process is characterized by the rates: k for the polymer to make a diffusive jump through the pore, q for unbinding of a chaperone, and the rate q kappa for binding (with a binding strength kappa); except for the case of no binding kappa=0 the presence of the chaperones give rise to an effective force that drives the translocation process…

The concept of entropic rectifier facing experiments

The transport of molecules in confined media is subject to entropic barriers. So theoretically, asymmetry of the confinement length may lead to molecular ratchets with entropy as the only driving force for the biased transport. We address experimentally this question by performing alternative ionic current measurements on electrolytes confined in neutral conical nanopores. In case anions and cations widely differ in size, we show that rectification of ionic current can be obtained that depends on ions size and cycle frequency, consistently with the entropic ratchet mechanism.