Transepithelial/transendothelial electrical resistance Measurement by Organic electrochemical transistor

Abstract

Electrical impedance sensing of biological systems, especially cultured epithelial cell layers, is now a common technique to monitor cell morphology, and cell layer/tissue integrity. Existing methods to measure electrical impdedance most often rely on a two electrode configuration, where low frequency signals are challenging to obtain for small devices and for tissues with high resistance, due to low current. Organic electrochemical transistors(OECTs) have been shown to efficiently transduce and amplify low-level ionic fluxes in biological systems into electronic output signals. Here we present the how to measure the transepithelial/transendothelial electrical resistance(TEER) by OECT. In this work, we apply from standard electrochemical impedance spectroscopy(EIS) analysis to OECT-based drain current measurement. The biotic/abiotic ensemble is modeled with a simple equivalent circuit and an analytical expression of the total impedance as a function of frequency is extracted. Our result provide improved impedance and oect based TEER measurment with optimized sensitivity.