Quantitative evaluation of nano-order micromotion of cultured cells using electric cell-substrate impedance sensing method

Electric cell-substrate impedance sensing (ECIS) system can detect electrically micro-motion of the cell cultured in the gold electrode, originally developed by I. Giaever et al. The ECIS system makes data continuously on resistance and capacitance values change in electric impedance by the cell micro-motion at real time. Human umbilical vein endothelial cells were cultured on the ECIS electrode, and measured after chemical substance (estrogen) stimulation electric impedance over 40 hours. A parameter analyzed cellular motion by using the precise mathematical model simulated cell electric impedance based on the Cole-Cole model. This mathematical model agreed with the experiment value over wide frequency range 25 Hz to 60 kHz. Impedance of the mathematical model in the ECIS system varied with the change in cell-cell distance A and cell-substrate distance h in the motion of the cultured cell. The parameter for the distance of A and h was defined as SA and Sh to do the simple and easy evaluation of the cell micro-motion. Furthermore, the actual dimension evaluation of A, h was tired from these parameters. A change in impedance following estrogen stimulation was analyzed by using the mathematical model, and changes in A and h were estimated.