Nonlinear ac responses of erythrocyte suspensions: Experiment and theory

When a suspension consisting of electric particles having nonlinear characteristics is subjected to a sinusoidal alternating current ac electric field, the electric response will generally consist of ac fields at frequencies of higher-order harmonics. We experimentally report on harmonic generation by erythrocytes subjected to an ac electric field. We find that both even and odd harmonics are sensitive to cell shapes, conductivities, field frequencies, and field magnitude. Theoretical analysis based on a phenomenological model yield predictions that are in excellent agreement with the experiments. Thus, it becomes possible to detect nonlinear characteristics, shapes, and conductivities of erythrocytes by measuring such ac responses. © 2007 American Institute of Physics. DOI: 10.1063/1.2817398