How to Choose a Proper Theoretical Analysis Model Based on Cell Adhesion and Nonadhesion Impedance Measurement

The accurate equivalent circuit model contributes to the better fitting of required cell characteristics, such as cell impedance, cell adhesion area, and cell-electrode distance. However, so many theoretical models on specific modules make it difficult for new researchers to understand the whole model of electrode system physically. Besides, the accurate theoretical model and the simplified calculations obviously contradict each other; therefore, it is confusing for many researchers to choose the proper theoretical model to calculate the specific parameters required. In this review, we first discuss the problems and suggestions of electrode system design for cell adhesion-based measurement in terms of parasitic capacitance, detection range of cell number, electric field distribution, and interelectrode distance. The design of electrode system for cell nonadhesion measurement was analyzed in terms of microchannel size and electrode position. Then, we discuss the advantages and disadvantages of various equivalent circuit models according to different requirements of researchers, and simultaneously provide a corresponding theoretical model for researchers. Various factors influencing electric impedance spectroscopy (EIS) such as the parasitic capacitance between microelectrodes, the changes of cell adhesion area and cell-electrode distance, the electrode geometry, and the surface conductivity of electrode were quantitatively analyzed to contribute to better understanding of the equivalent models. Finally, we gave advice to optimize the theoretical models further and perspectives on building uniform principles of theoretical model optimization in the future.