A micro-electrode array biosensor for impedance spectroscopy of human umbilical vein endothelial cells

We report on a novel, radial micro-electrode array biosensor for impedance spectroscopy (IS) of Human Umbilical Vein Endothelial Cells (HUVECs). The electrical parameters of the HUVEC monolayer, which are important indicators of physiological factors such as cell–cell interactions and cell motility, were measured using this micro-electrode biosensor. HUVEC monolayer was cultured directly on the surface of the micro-electrode array. Impedance modulus and the phase angle of HUVEC's in the frequency range from 12.5 kHz to 500 kHz were recorded and studied. A modified Randles cell (MRC) equivalent circuit was used to extract the electrical parameters of transendothelial monolayer. Differential analysis of HUVEC and Hanks’ Balanced Salt Solution (HBSS) impedance data shows electrical resonance at 52.5 kHz. The value of capacitance at resonance was measured to be ∼25 μF/cm2.