Decoding Electrophysiological Signals with Organic Electrochemical Transistors

Abstract

The organic electrochemical transistor (OECT) has unique characteristics that distinguish it from other transistors and make it a promising electronic transducer of biological events. High transconductance, flexibility, and biocompatibility render OECTs ideal for detecting electrophysiological signals. Device properties such as transconductance, response time, and noise level should, however, be optimized to adapt to the needs of various application environments including in vitro cell culture, human skin, and inside of a living system. This review includes an overview of the origin of electrophysiological signals, the working principles of OECTs, and methods for performance optimization. While covering recent research examples of the use of OECTs in electrophysiology, a perspective is provided for next-generation bioelectric sensors and amplifiers for electrophysiology applications.

Adaptive Biosensing and Neuromorphic Classification Based on an Ambipolar Organic Mixed Ionic–Electronic Conductor

“…The ability to amplify low signal‐to‐noise ratio biosignals is also important, particularly for small signals like EEG. [ 27 ] However, any computational action such as a decision or classification is still made externally. In order to judge and process a plethora of signals, local amplification, and normalization is needed.…”

A guide for the characterization of organic electrochemical transistors and channel materials

“…Here, τ On can be calculated from τ On = R S · C Ch after modeling the impedance spectra with an equivalent circuit model or through the cutoff frequency ( f c ), which describes the frequency upper boundary that OECTs can achieve for signal acquisition and amplification (Fig. 4B), based on eqn (4): 117 where f c corresponds to the frequency of the g m at −3 dB ( ca. 0.707 g max ).…”

Materials design and applications of n-type and ambipolar organic electrochemical transistors

“…In addition, OECTs can work in aqueous media, exhibiting good biocompatibility, suitable for direct interfacing with biological systems. These features have made OECTs a promising technology for various applications such as chem/biosensing, 5 electrophysiological recording, 6 and neuromorphic computing. [7][8][9] Complementary logic circuits serve as fundamental building blocks for constructing intricate logic circuits.…”