Anisotropic conductivity for single-cell electroporation simulation with tangentially dispersive membrane

Abstract

Under the application of intensive nanosecond pulsed electric fields (nsPEFs), the electric shielding of the cellular membrane can be broken down and the permeability of the cellular membrane would augment dramatically, which is known as electroporation. This effect has been successfully used in drugs transmembrane transport and non-thermal tumor ablation. In this study, we propose that nsPEFs induce the anisotropic conductivity for electroporation with the evidence that conductivity of the cellular membrane increases mostly in the normal direction, with full consideration of the tangential dielectric relaxation effect of the cellular membrane. The corresponding simulation models are built to verify and analyze the impact of the normal electroporation and tangential dispersion on the electroporation process. The typical influential factors and indicators for normal electroporation and tangential dispersion, transmembrane potential, polarization vectors, conductivity tensor components, etc., are probed in the spherical cell model. Results show that normal electroporation would reduce the local pore density in dispersive models that results in a relative higher transmembrane voltage, and tangential dispersion would increase the pore density, in the meantime, expedite the electroporation process. Taking the normal electroporation and tangential dispersion into account can extend the electroporated area, increase the pore amount, and attenuate the bipolar cancelation effect in terms of the spatial distribution of nanopores. The model in this study can reflect the more accurate spatiotemporal evolution of the anisotropic parameters in the nsPEFs induced electroporation than proposed models, which is instructive to parameter selection of the nsPEF in applications.