Surface viscosity, diffusion, and intermonolayer friction: simulating sheared amphiphilic bilayers.
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.
Shkulipa
S A
SA
Computational Dispersion Rheology, Faculty of Science and Technology, University of Twente, Enschede, The Netherlands.
den Otter
W K
WK
Briels
W J
WJ
D003198:Computer Simulation; D004058:Diffusion; D017276:Friction; D008051:Lipid Bilayers / Q000737:chemistry*; D008560:Membrane Fluidity; D044085:Microfluidics / Q000379:methods*; D008956:Models, Chemical; D008958:Models, Molecular; D008968:Molecular Conformation; D044367:Phase Transition; D033081:Shear Strength; D013499:Surface Properties; D014783:Viscosity
D008051:Lipid Bilayers