Surface viscosity, diffusion, and intermonolayer friction: simulating sheared amphiphilic bilayers.

S A Shkulipa; W K den Otter; W J Briels

doi:10.1529/biophysj.105.062653

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Surface viscosity, diffusion, and intermonolayer friction: simulating sheared amphiphilic bilayers.

S A Shkulipa·W K den Otter·W J Briels

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Abstract

The flow properties of an amphiphilic bilayer are studied in molecular dynamics simulations, by exposing a coarse grained model bilayer to two shear flows directed along the bilayer surface. The first field, with a vorticity perpendicular to the bilayer, induces a regular shear deformation, allowing a direct calculation of the surface viscosity. In experiments this property is measured indirectly, by relating it to the diffusion coefficient of a tracer particle through the Saffman-Einstein expression. The current calculations provide an independent test of this relation. The second flow field, with a vorticity parallel to the bilayer, causes the two constituent monolayers to slide past one another, yielding the interlayer friction coefficient.

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Computer Simulation Diffusion Friction Lipid Bilayers Membrane Fluidity Microfluidics Models, Chemical Models, Molecular Molecular Conformation Phase Transition Shear Strength Surface Properties Viscosity Journal Article Research Support, Non-U.S. Gov't

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S A Shkulipa, W K den Otter, W J Briels. 2005-05-13. Surface viscosity, diffusion, and intermonolayer friction: simulating sheared amphiphilic bilayers.. https://doi.org/10.1529/biophysj.105.062653

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