Electrical cell impedance spectral mesoscopic model applied to experimental data of variable size microelectrodes

ANA CARLA BUCHINI LABAYEN; BELLOTTI, MARIELA I.; WALTER BAST; A.CLAUSSE FABIAN BONETTO Y J.CONVERTI

PHYSICAL REVIEW E

AMER PHYSICAL SOC

Lugar: New York; Año: 2022

1539-3755

We applied the Electric Cell-substrate Impedance Sensing (ECIS) technique to monolayers ofMadin-Darby Canine Kidney type II (MDCK II) cells cultured on microelectrodes of dierent sizes.We analyzed the eect of the microelectrode radius on the parameters provided by existing ECISmodels. The cellular properties inferred from the models should be invariant to the change inthe microelectrode radius used for the measurements, since these properties are inherent to thetype of cells studied. The current standard model, the Giaever-Keese (GK) model, derived fromelectrical balances of a single cell extended to innity by suitable boundary conditions, assumesan innite microelectrode. The model was tted to experimental data acquired with a largeradius microelectrode, which can be considered innite for practical purposes. We computed theimpedance of the other cell-covered microelectrodes from the parameters obtained with the GKmodel, resulting in values strongly discrepant with the experimental data for small microelectrodes.We repeated the process with the Mean Field (MF) model, an alternative model that depends on themicroelectrode radius but not on the cell radius. In this paper, we introduce the Mesoscopic model,an analytical model that simultaneously includes the properties of an individual cell and the sizesof the microelectrode and the insulator (region between the microelectrode and the ground). Theimpedances calculated with the Mesoscopic model were in excellent agreement with experimentaldata. Finally, the Mesoscopic model reduces to the MF model when the insulator goes to innite,and to the GK model when it goes to zero.