Publications and Research

Document Type


Publication Date



Detection sensitivity is a crucial criterion in the design and application of ECIS sensors. The influence of sensing electrode dimension on detection sensitivity is investigated in this paper. Eight types of ECIS sensors were fabricated, and their experimental results reveal that smaller-radius working electrodes generate more sensitive impedance shift to cell density change. Also, the smaller radius of working electrodes yield higher impedance values, which improves signal-to-noise ratio. In a range from 1.0 mm to 3.5 mm, the distance between the working and counter electrodes does not affect impedance measurements. However, the distance should be large enough to prevent the current from directly bypassing the cells between the electrodes. A mathematical model has been developed to analyze the distribution of electric potential and current over the sensing electrodes of ECIS sensors, which is helpful in understanding the mechanisms of ECIS. This mathematical model, supported by experimental data and finite element analysis, is able to illustrate a quantitative relationship between cell impedance and cell characteristics. This model can be used to optimize the design of ECIS sensors and interpret cell behavior.


© 2017. This manuscript version is made available under the CC-BY-NC-ND 4.0 license

This work was originally published in Sensors and Actuators B: Chemical, available at

Revised Tables.docx (43 kB)
revised tables

Revised Figures.docx (5097 kB)
revised figures



To view the content in your browser, please download Adobe Reader or, alternately,
you may Download the file to your hard drive.

NOTE: The latest versions of Adobe Reader do not support viewing PDF files within Firefox on Mac OS and if you are using a modern (Intel) Mac, there is no official plugin for viewing PDF files within the browser window.