Electric Cell-Substrate Impedance Sensing
Electric Cell-Substrate Impedance Sensing, or ECIS for short, describes a very broadly applicable scientific method for examining living animal cells in vitro . H. outside a living organism in a controllable laboratory environment.
The method is based on growing the cells on a flat gold film electrode that is located on the bottom of a culture dish (e.g. Petri dish ). The alternating current resistance ( impedance ) of the cell-covered electrode is measured at one or more frequencies as a function of time. Since the cells behave like dielectric particles due to the insulating properties of their plasma membrane , the impedance will increase with increasing fouling of the electrode until a continuous cell layer has formed. In continuous cell layers, the measured impedance of the cell-covered electrode is largely determined by the cell shape. If the cell shape changes as a result of an external stimulus, the current paths around and through the cell change so that the measured impedance changes accordingly. By means of time-resolved impedance measurement, changes in cell shape can thus be monitored in a time-resolved manner and in sub-microscopic resolution and used for bioanalytical purposes.
Since the three-dimensional shape of animal cells reacts with high sensitivity to changes in metabolism or a chemical, biological or physical influence, the ECIS method is used in a variety of applications in biomedical laboratories with a focus on cell biology . It can be used for active ingredient and cytotoxicity screening or to examine the adhesion of animal cells to the substrate.
Web links
- An In-Depth Analysis of Electric Cell − Substrate Impedance Sensing To Study the Attachment and Spreading of Mammalian Cells, in: Anal. Chem. 2002 , 74 , 1333-1339; doi : 10.1021 / ac011104a .