Dynamics of a bilayer membrane with membrane-solvent partial slip boundary conditions

TL;DR

This paper models the dynamics of bilayer membranes considering partial slip boundary conditions, deriving coupled equations and revealing how friction influences membrane behavior, with implications for understanding membrane-fluid interactions.

Contribution

It introduces a theoretical framework using Onsager's principle to incorporate partial slip boundary conditions into membrane dynamics models.

Findings

Friction coefficients modify effective fluid viscosities.

Permeation and parallel slip effects are negligible in typical lipid bilayers.

Derived coupled equations for membrane height and lipid density.

Abstract

We discuss the dynamics of a bilayer membrane with partial slip boundary conditions between the monolayers and the bulk fluid. Using Onsager's variational principle to account for the associated dissipations, we derive the coupled dynamic equations for the membrane height and the excess lipid density. The newly introduced friction coefficients appear in the renormalized fluid viscosities. For ordinary lipid bilayer membranes, we find that it is generally justified to ignore the effects of permeation and parallel slip at the membrane surface.