Characteristic time for the end monomers of a spherically-confined polymer to find a nano-pore

Abstract

Translocation of a polymer through a nano pore is relevant in a variety of contexts such as passage of RNAs through a nuclear pore, transportation of proteins across a membrane, and ejection of viral DNA into a host cell. An essential step in polymer translocation is for the end monomers to search the pore. This process requires a characteristic time, referred to as the ``attempt time'' in this work. Here, we study the attempt time $\tau$ of a confined polymer by combining a scaling approach and Langevin dynamics simulations. For a moderately-strongly confined polymer, our results suggest that $\tau\sim R^{3.67}$ for $R>P$ and $\tau\sim R^{2.67}$ for $R