Measurement of the cell-substrate separation and the projected area of an individual adherent cell using electric cell-substrate impedance sensing

This work presents an electrical technique called electric cell-substrate impedance sensing to measure the cell-substrate separation and the projected area of an individual adherent cell. Cell adhesion and cell spreading are fundamental processes of adherent cells. By recording changes in the cell-substrate separation, the projected area, or both properties with time, the dynamics of cell spreading and cell adhesion can be studied. The advantage of this electrical technique is that it enables a measurement of many individual cells simultaneously. This is a great benefit to the study of heterogeneity in cell populations. The research consisted of building a custom impedance sensing setup, designing an in vitro assay to record an impedance spectrum of an individual living cell, and developing a data analysis method to obtain two properties of the cell from curve-fitting of the impedance spectrum. The values of the cell-substrate separation and the projected area of an individual cell were within the expected ranges and in agreement with those obtained from optical microscopy.