Permeation through a lamellar stack of lipid mixtures

¹ Department of Chemistry, Graduate School of Science and Engineering, Tokyo Metropolitan University Tokyo 192-0397, Japan
² Raymond and Beverly Sackler School of Physics and Astronomy, Tel Aviv University Ramat Aviv, Tel Aviv 69978, Israel

Received: 7 September 2017
Accepted: 27 November 2017

Abstract

We study material transport and permeation through a lamellar stack of multi-component lipid membranes by performing Monte Carlo simulations of a stacked two-dimensional Ising model in the presence of permeants. In the model, permeants are transported through the stack via in-plane lipid clusters, which are inter-connected in the vertical direction. These clusters are formed transiently by concentration fluctuations of the lipid mixture, and the permeation process is affected especially close to the critical temperature of the binary mixture. We show that the permeation rate decays exponentially as a function of temperature and permeant lateral size, whereas the dependency on the characteristic waiting time obeys a stretched exponential function. The material transport through such lipid clusters can be significantly affected around physiological temperatures.