Single Stranded DNA Translocation Through A Nanopore: A Master Equation Approach

TL;DR

This paper presents a master equation model for voltage-driven ssDNA translocation through nanopores, explaining translocation time distributions and their dependence on polymer length, voltage, and polymer-pore interactions.

Contribution

It introduces a novel master equation approach to analyze translocation times, capturing the effects of system parameters and matching experimental observations.

Findings

Translocation time distribution can be mono- or double-peaked.

Most probable translocation time scales linearly with polymer length.

Translocation time inversely depends on voltage, with power depending on initial conditions.

Abstract

We study voltage driven translocation of a single stranded (ss) DNA through a membrane channel. Our model, based on a master equation (ME) approach, investigates the probability density function (pdf) of the translocation times, and shows that it can be either double or mono-peaked, depending on the system parameters. We show that the most probable translocation time is proportional to the polymer length, and inversely proportional to the first or second power of the voltage, depending on the initial conditions. The model recovers experimental observations on hetro-polymers when using their properties inside the pore, such as stiffness and polymer-pore interaction.