Electric Field Induced Deformations of Biomimetic Fluid Membranes

We investigate the coupling between the mechanics of fluid membranes and transmembrane electric potential using as a model system the giant vesicle (closed bilayer membrane made of lipids or polymers). In DC electric pulses, an initially quasispherical giant vesicle can become a spherocylinder. The edge between the spherical cap and the cylindrical section appears to separate porated (conducting) and intact (insulating) regions of the membrane. The location of the edge provides a quick estimate for the critical poration voltage of a membrane. A uniform AC electric field affects membrane fluctuations, increasing the effective bending rigidity and decreasing the effective membrane tension. Moreover, a very deflated vesicle can become an asymmetric dumbbell. In the case of multicomponent membranes, the miscibility temperature (at which domains form in an initially homogeneous membrane) decreases with applied electric field strength.