Passage Times for Polymer Translocation Pulled through a Narrow Pore

Abstract

We study the passage times of a translocating polymer of length $N$ in three dimensions, while it is pulled through a narrow pore with a constant force $F$ applied to one end of the polymer. At small to moderate forces, satisfying the condition $F{N}^{\nu }/k_{B}T\lesssim 1$, where $\nu \approx 0.588$ is the Flory exponent for the polymer, we find that ${\tau }_N$, the mean time the polymer takes to leave the pore, scales as $N^{2+\nu }$ independent of $F$, in agreement with our earlier result for F=0. At strong forces, i.e., for $F{N}^{\nu }/k_{B}T\gg 1$, the behaviour of the passage time crosses over to ${\tau }_N\sim N^2/F$. We show here that these behaviours stem from the polymer dynamics at the immediate vicinity of the pore -- in particular, the memory effects in the polymer chain tension imbalance across the pore.

7 pages, 4 figures, 6 eps figure files, minor expressions changed, references updated; to appear in Biophys. J

Cited by in corpus (1)

• Local Strain Relaxation Dictates Polymer Melt Viscosity