Organic Electrochemical Transistors as an Emerging Platform for Bio-Sensing Applications: A Review

Abstract

Organic electrochemical transistors (OECTs) have been recognized as a major emerging technology in the area of flexible electronics in the last decade. Although they have yet to be incorporated in common electronic fabrication technologies, they have considerably advanced as an emerging platform for biosensing applications. The paper provides a comprehensive and critical review of the most important advances in the field of OECT-based biosensors. A brief description of the device physics is given with the most important equations and a comparison has been made with the conventional MOSFET devices and characteristic equations. The use of OECTs as an emerging biosensing platform has been explored and their application as biomolecule, enzyme, bacteria, viruses, cells, nucleotide detectors as well as electrophysiological and wearable sensors has been reported. Furthermore, trends have been extracted and described in the paper in terms of fabrication technologies, electrode materials and most importantly, the semiconducting polymer. Additionally, future perspectives on the development and fabrication technologies of these devices have been further explored.

Organic Electrochemical Transistors: An Emerging Technology for Biosensing

“…Furthermore, DNA/RNA sensing based on OECT sensors has become a crucial technique to monitor concentrations of several nucleotide‐based cancer biomarkers. [ 134 ] The reported performances of OECT‐based immunosensors are highly promising when accompanied with low operating voltages, biocompatibility, and flexibility.…”

The effect of side chain engineering on conjugated polymers in organic electrochemical transistors for bioelectronic applications

“…42,43 In bioelectronic applications, transconductance generally serves as a function of the parameter of interest (e.g., target ion or metabolite concentration). 44 Consequently, the high sensitivity of OECTs stems from enhanced resolution at reduced detection limits, which is accounted for by the gate voltage/channel current interconnection. 45 The combination of such low operational voltage and high transconductance create beneficial conditions for the precise examination of biological events.…”

“…4 presents the comparison of the transconductance values of a collection of the reported OMIEC materials. 44 …”

Current‐Driven Organic Electrochemical Transistors for Monitoring Cell Layer Integrity with Enhanced Sensitivity

“…[58] Besides aqueous electrolyte, typically defined by a PMMA-well, the possibility to use solid electrolytes, using ionic liquids, offer a great potential for applications, for example, for wearable electronics, due to its wide variety of processing methods. [59] The channel geometries are determining the channel´s volumetric capacitance. Recently the group of Hsing et al tuned the sensitivity of the OECT as an impedance sensor by optimizing the impedance relation of the channel and the integrated cell layer.…”