Polymer translocation through a nanopore driven by binding particles: Influence of chain rigidity

作者：Wancheng Yu, Kaifu Luo · 发表于：Physical Review E · 年份：2014 · DOI：10.1103/physreve.90.042708 · 被引用次数：18 · 研究领域：Nanopore and Nanochannel Transport Studies、Fuel Cells and Related Materials、Thermal properties of materials

We investigate the influence of chain rigidity on the dynamics of polymer translocation in the presence of binding particles (BPs) through a nanopore using two-dimensional Langevin dynamics simulations. With increasing chain rigidity $\ensuremath{\kappa}$, the mean translocation time $\ensuremath{\langle}\ensuremath{\tau}\ensuremath{\rangle}$ increases monotonically due to an increase in the radius of gyration and a decrease in the center of mass velocity. Particularly for weak binding, we further find that $\ensuremath{\langle}\ensuremath{\tau}\ensuremath{\rangle}$ shows a power-law behavior with the persistence length ${l}_{p}$. Analysis indicates a scaling relation between the average velocity of the center of mass of a chain $\ensuremath{\langle}{v}_{\text{c.m.}}\ensuremath{\rangle}$ and ${l}_{p}$. As the chain becomes stiffer, the distribution of the translocation time $\ensuremath{\tau}$ approximates the Gaussian distribution and gets broader with the peak position being shifted towards longer translocation time. The corresponding translocation coordinate ${s}_{\text{max}}$ of the maximum waiting time gets smaller with increasing chain rigidity. Finally, under an extremely low BP concentration, $\ensuremath{\langle}\ensuremath{\tau}\ensuremath{\rangle}$ shows a minimum for small $\ensuremath{\kappa}$, while it decreases monotonically for large $\ensuremath{\kappa}$ with increasing binding energy. Our results suggest a nontrivial effect of the intrinsic property of chain...