Physical model for electroporation of cell membranes

By treating the human cell structure as a layered dielectric capacitor, a physical model has been developed for the electroporation of cell membranes. It is shown, from dielectric physics and using Gibbs potential/free-energy principles, that hydrogen bonds (H-bonds) in the membrane layer can degrade at modest levels of external field (∼1 kV/cm). Time-dependent dielectric breakdown of the membrane layer occurs at ∼10 kV/cm, and nearly instantaneous membrane breakdown (breakdown strength) occurs at ∼40 kV/cm. Dielectric breakdown of the cell membrane layer leads to pore formation within this layer. Pore formation generally leads to cell necrosis or apoptosis. The Gibbs potential (which contains both linear and quadratic terms in the field) is found to be very useful in describing the electroporation process. The linear field term is critically important for the membrane degradation rate, while the quadratic term is critically important for the amount of membrane damage (pore formation) during the breakdown event. This physical model may enhance our understanding of cancer cell electroporation.