Huclova, Sonja; Erni, Daniel; Fröhlich, Jürg:

Modelling effective dielectric properties of materials containing diverse types of biological cells

In: Journal of Physics: D Applied Physics, Jg. 43 (2010) ; Nr. 36, S. 365405-1-10
ISSN: 0022-3727, 1361-6463
Zeitschriftenaufsatz / Fach: Elektrotechnik
An efficient and versatile numerical method for the generation of different realistically shaped biological cells is developed. This framework is used to calculate the dielectric spectra of materials containing specific types of biological cells. For the generation of the numerical
models of the cells a flexible parametrization method based on the so-called superformula is applied including the option of obtaining non-axisymmetric shapes such as box-shaped cells and even shapes corresponding to echinocytes. The dielectric spectra of effective media containing various cell morphologies are calculated focusing on the dependence of the spectral features on the cell shape. The numerical method is validated by comparing a model of
spherical inclusions at a low volume fraction with the analytical solution obtained by the Maxwell–Garnett mixing formula, resulting in good agreement. Our simulation data for different cell shapes suggest that around 1MHz the effective dielectric properties of different cell shapes at different volume fractions significantly deviate from the spherical case. The most pronounced change exhibits •eff  between 0.1 and 1MHz with a deviation of up to 35% for a box-shaped cell and 15% for an echinocyte compared with the sphere at a volume fraction of 0.4. This hampers the unique interpretation of changes in cellular features measured by dielectric spectroscopy when simplified material models are used.
(Some figures in this article are in colour only in the electronic version)