Biomolecule sensors based on organic electrochemical transistors

Biosensors based on organic electrochemical transistors (OECTs) have been a research highlight in recent years owing to their remarkable biocompatibility, low operating voltage, and substantial signal amplification capability. Especially, as an emerging fundamental device for biosensing, OECTs show great potential for pH, ions, molecules, and biomarker sensing. This review highlights the research progress of biomolecule sensors based on OECTs, focusing on recent publications in the past 5 years. Specifically, OECT-based biomolecule sensors for small molecules (glucose, dopamine, lactate, etc. that act as signals or effectors), and macromolecules (DNA, RNA, proteins, etc. that are often used as markers in physiology and medicine), are summarized. Additionally, emerging technologies and materials used to enhance sensitivity, detection limits, and detection ranges are described comprehensively. Last, aspects of OECT-based biomolecule sensors that need further improvement are discussed along with future opportunities and challenges.