Measurement of Cellular Behavior by Electrochemical Impedance Sensing

There is a great demand for label-free in vitro assays in a high-throughput context, in order to measure cell viability and analyze cellular functions like cell migration or cell differentiation under noninvasive conditions. Here, we describe impedance measurement to quantify dynamic changes on cell morphology in real time. In order to monitor physiological changes, cells are grown in tissue culture vessels where gold electrodes are incorporated at the bottom. An alternating current signal of several kHz is applied to the electrodes and the resulting voltage is measured to calculate the cellular impedance. Since impedance is closely related to the area of the electrodes covered by the growing cells, parameters such as cell number, size of the cells attached to the electrodes, and cell-cell and cell-substrate/extracellular matrix interactions contribute to the overall impedance values.