Nanoparticle-assisted polymer translocation through a nanopore

Abstract

The effect of interaction between immobile nanoparticle and polymer on the translocation process was investigated using a three dimensional Langevin molecular dynamics. Several parameters for describing the translocation time, the polymer shape, and the dispersion of polymer were calculated. Placing a purely repulsive nanoparticle in front of the nanopore not only increases the translocation time but also cause the translocation process to be longer than the translocation process without the presence of nanoparticle. On the other hand, the attractive–repulsive nanoparticle decreases the translocation time for both having a bigger nanoparticle and stronger interaction between polymer and nanoparticle. Simulation results show that the nanoparticle effect on the translocation velocity depends on the binding energy (BE) and by increasing the BE it changes from a decelerator to an accelerator.Moreover, the waiting time plots show a significant difference between the translocation with or without the nanoparticle and change from step-like to the bell-shaped.Analyzing the center of the mass and shape factor, show that increasing the nanoparticle–nanopore distance will elongate the polymer and manifest itself on the shape of the polymer.