Passive electrical properties of cultured murine lymphoblast (L5178Y) with reference to its cytoplasmic membrane, nuclear envelope, and intracellular phases

Abstract

Dielectric dispersion measurements over a frequency range 0.01–100 MHz were made with the suspensions of a cultured cell line, mouse lymphoma L5178Y, and an attempt to explain the observed dielectric behavior by taking explicitly into consideration the possible involvement of cell nucleus has been presented. The use of a conventional “single-shell” model in which the cell is represented by a homogeneous sphere coated with a thin limiting shell phase did not duplicate the observed dispersion curves, whereas a “double-shell” model in which one additional concentric shell is incorporated into the “single-shell” model gave a much better fit between the observed and the predicted dispersion curves. Based on the latter model, we analyzed the raw data of dielectric measurements to yield a set of plausible electrical parameters for the lymphoma cell:C _M ≅1.0μF/cm²,C _N ≅0.4μF/cm², ε_k≅300, κ_c/κ_a≅0.9, and κ_k/κ_c≅0.7. Here,C _M andC _N are the specific capacities of plasma and nuclear membranes; ε and κ are the dielectric constant and conductivity with subscripta, c andk referring respectively to the extracellular, the cytoplasmic and the karyoplasmic phases.