Polymer translocation induced by adsorption

Abstract

We study the translocation of a flexible polymer through a pore in a membrane induced by its adsorption on the trans side of the membrane. When temperature T is higher than Tc, the adsorption–desorption transition temperature, the attractive interaction between polymer and membrane plays little role in affecting polymer conformation, leading to translocation time that scales as τ∼L3, where L is the polymer contour length. When T<Tc, however, the translocation time undergoes a sharp crossover to τ∼L2 for sufficiently long polymers, following the second-order conformational (adsorption) transition. The translocation time is found to exhibit the crossover around T=Tc′, which is lower than Tc for polymers shorter than a critical length (N<Nc).