Thermal Tunneling of Homopolymers through Amphiphilic Membranes.

ACS Macro Lett

Leibniz-Institut für Polymerforschung Dresden e.V., Hohe Straße. 6, 01069 Dresden, Germany.

Published: March 2017

We propose a theory to predict the passive translocation of flexible polymers through amphiphilic membranes. By using a generic model for the potential felt by a monomer across the membrane we calculate the free energy profile for homopolymers as a function of their hydrophobicity. Our model explains the translocation window and the translocation rates as a function of chain hydrophobicity in quantitative agreement with simulation results. The potential model leads to a new adsorption transition where chains switch from a one-sided bound adsorbed state into a bridging state through the membrane core by increasing the hydrophobicity beyond a critical value. We demonstrate that the hydrophobicity leading to the fastest translocation coincides with the solution for the critical point of adsorption in the limit of long chains.

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http://dx.doi.org/10.1021/acsmacrolett.6b00980DOI Listing

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