Dielectric Cytometry with Three-Dimensional Cellular Modeling

We have developed what we believe is an efficient method to determine the electric parameters (the specific membrane capacitance Cm and the cytoplasm conductivity κi) of cells from their dielectric dispersion. First, a limited number of dispersion curves are numerically calculated for a three-dimensional cell model by changing Cm and κi, and their amplitudes Δɛ and relaxation times τ are determined by assuming a Cole-Cole function. Second, regression formulas are obtained from the values of Δɛ and τ and then used for the determination of Cm and κi from the experimental Δɛ and τ. This method was applied to the dielectric dispersion measured for rabbit erythrocytes (discocytes and echinocytes) and human erythrocytes (normocytes), and provided reasonable Cm and κi of the erythrocytes and excellent agreement between the theoretical and experimental dispersion curves.