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Abstract Organic electrochemical transistors (OECTs) are gaining significant attention due to their high sensitivity, customizability, ease of integration, and low‐cost manufacturing. In this paper, we design and develop a flexible dual‐gate OECT based on laser‐scribed graphene (LSG) with modified OECT gates for the detection of dopamine and glutamate, two critical neurotransmitters (NTs). The developed OECTs are fully carbon‐based and environmentally friendly. By modifying the gates of OECTs with biopolymer chitosan and L‐Glutamate oxidase enzyme, highly selective and sensitive measurements are successfully achieved with detection limits of 5 nmfor dopamine and 1 µmfor glutamate, respectively. The modified dual‐gate shows no interference between the detections of two neurotransmitters, making it a promising tool for customized multi‐neurotransmitter analysis. The results demonstrate the potential of LSG‐based OECTs in customizable biosensing applications, offering a flexible, cost‐effective platform for biomedical disorder diagnostics.
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A hybrid transistor with transcriptionally controlled computation and plasticity
Abstract Organic electrochemical transistors (OECTs) are ideal devices for translating biological signals into electrical readouts and have applications in bioelectronics, biosensing, and neuromorphic computing. Despite their potential, developing programmable and modular methods for living systems to interface with OECTs has proven challenging. Here we describe hybrid OECTs containing the model electroactive bacteriumShewanella oneidensisthat enable the transduction of biological computations to electrical responses. Specifically, we fabricated planar p-type OECTs and demonstrated that channel de-doping is driven by extracellular electron transfer (EET) fromS. oneidensis. Leveraging this mechanistic understanding and our ability to control EET flux via transcriptional regulation, we used plasmid-based Boolean logic gates to translate biological computation into current changes within the OECT. Finally, we demonstrated EET-driven changes to OECT synaptic plasticity. This work enables fundamental EET studies and OECT-based biosensing and biocomputing systems with genetically controllable and modular design elements.
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- PAR ID:
- 10491913
- Publisher / Repository:
- Nature Publishing Group
- Date Published:
- Journal Name:
- Nature Communications
- Volume:
- 15
- Issue:
- 1
- ISSN:
- 2041-1723
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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