Electrostatics: Electric field treatments and electroporation

Electric Field Treatment (EFT) is a relatively recent innovation in medicine that allows for the electric polarization of patient tissue in a clinical setting. This procedure is particularly useful on a molecular level. For example, EFT can be used to rearrange charges on the cell membrane, resulting in an induced transmembrane potential. It can also be used to excite or inhibit voltage-gated ion channels, which can be useful in treating patients with intracellular sodium deficiency.

One researcher is interested in utilizing EFT to deliver drugs through electroporation. This process involves temporarily permeabilizing the membrane through brief exposure to an electric field. To begin her study, she sets up two large metal plates separated by a distance D are charged using a battery of voltage V. This creates a region of uniform and constant electric field throughout the region between the plates. Various charges (either + or -) can then be shot downward through the region at the midway point between the plates.

Figure 1. A diagram of the experiment apparatus.

Source: Schoenbach, K. Stark, R. Jingdong, D. Aly, R. Beebe, S. Buescher, E. (2000). Biological/medical pulsed electric field treatments. Power Modulator Symposium. Norfolk, VA, USA.