Giant vesicles in electric fields

Abstract

This review is dedicated to electric field effects on giant unilamellar vesicles, a cell-size membrane system. We summarize various types of behavior observed when vesicles are subjected either to weak AC fields at various frequency, or to strong DC pulses. Different processes such as electrodeformation, -poration and -fusion of giant vesicles are considered. We describe some recent developments, which allowed us to detect the dynamics of the vesicle response with a resolution below milliseconds for all of these processes. Novel aspects on electric field effects on vesicles in the gel phase are introduced.

Hydrodynamic mechanisms of cell and particle trapping in microfluidics

“…122 They are generally used in biophysical studies of membranes and red blood cells dynamics. 123 Suspended in steady shear flow, vesicles have been observed to exhibit different dynamical modes including tank-treading motion where the vesicle deforms into an ellipsoidal particle with a stationary orientation with respect to the flow direction while its membrane is circulating about its interior. 124 It is notable that in case of a rigid ellipsoid, the particle does not maintain a fixed inclination but will start to tumble in an unsteady fashion.…”

Ellipsoidal Relaxation of Deformed Vesicles

“…Giant unilamellar vesicles (GUVs) with dimensions of living cells and controlled membrane composition constitute ideal model systems to characterize the properties of lipid assemblies [2]. A variety of techniques have been developed to probe vesicle mechanics, including AFM [3], optical and magnetic stretching [4,5], micropipette aspiration [6], tether pulling [7], shear-flow-based deformation [8], fluctuation spectroscopy [9], and electrodeformation [10][11][12]. In each case (except fluctuation spectroscopy), the common strategy is to investigate the deforming response of the membrane via the application of external forcing.…”

The current-voltage relation for electropores with conductivity gradients

“…This approximation is appropriate for salt-based solutions, such as in vesicle electroporation experiments. 36 For biological cells, and in particular in the cytoplasm, the electrolyte solution has a more complex composition involving both small ions 41 and charged macromolecules ͑proteins, DNA, etc.͒. The latter often possess relatively large charge numbers and small diffusivities.…”