Polymer translocation: a nonequilibrium process
Abstract
3D Langevin dynamics simulations of the capture and translocation of polymers
through a nanopore are conducted for several polymer lengths and two
different Péclet values (that quantify the drift-diffusion balance of the system).
By measuring the average conformation of the polymer and the average duration
of each stage, simulations of the capture process reveal an elongated
polymer approaching the nanopore and either remains elongated or becomes
compressed just prior to translocation depending on the drift-diffusion balance.
This is in direct contrast with the standard approach of simulating only the
translocation process where the polymer is assumed to start translocation in an
equilibrated state. The conformational differences directly impact scaling results
of the translocation time by polymer length, where, even on a qualitative
level, simulations that assume equilibration may yield incorrect results. The
capture process is therefore an essential step for modelling and establishes the
nonequilibrium nature of the translocation process.