Organic electrochemical transistor arrays for real-time mapping of evoked neurotransmitter release in vivo
Abstract
Though neurotransmitters are essential in neural signal transmission, techniques for in vivo analysis are still limited. Here, we describe an organic electrochemical transistor array (OECT-array) technique for monitoring catecholamine neurotransmitters (CA-NTs) in rat brains. The OECT-array is an active sensor with intrinsic amplification capability, allowing real-time and direct readout of transient CA-NT release with a sensitivity of nanomolar range and a temporal resolution of several milliseconds. The device has a working voltage lower than half of that typically used in a prevalent cyclic voltammetry measurement, and operates continuously in vivo for hours without significant signal drift, which is inaccessible for existing methods. With the OECT-array, we demonstrate simultaneous mapping of evoked dopamine release at multiple striatal brain regions in different physiological scenarios, and reveal a complex cross-talk between mesolimbic and nigrostriatal pathways, which is heterogeneously affected by the reciprocal innervation between ventral tegmental area and substantia nigra pars compacta.
Data availability
All data generated or analysed during this study are included in the manuscript and supporting files. Source data files have been provided as supplementary files.
Article and author information
Author details
Funding
General Research Funds (11278616)
- Peng Shi
General Research Funds (11218015)
- Peng Shi
General Research Funds (11203017)
- Peng Shi
Health and Medical Research Fund (06172336)
- Peng Shi
Collaborative Research Funds (C5015-15G)
- Feng Yan
- Peng Shi
The funders provided resources for the study design, data collection, and interpretation.
Reviewing Editor
- Mehmet Fatih Yanik, Massachusetts Institute of Technology, United States
Ethics
Animal experimentation: All experimental procedures involving animals were approved by the university Animal Ethics Committee. Animal licenses, (16-97) in DH/HA&P/8/2/5 Pt.5 and (18-129) in DH/SHS/8/2/5 Pt.4, were approved by Department of Health of the Government of Hong Kong Special Administration Region.
Version history
- Received: July 19, 2019
- Accepted: February 10, 2020
- Accepted Manuscript published: February 11, 2020 (version 1)
- Version of Record published: March 16, 2020 (version 2)
Copyright
© 2020, Xie et al.
This article is distributed under the terms of the Creative Commons Attribution License permitting unrestricted use and redistribution provided that the original author and source are credited.
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Organic electrochemical transistor arrays for real-time mapping of evoked neurotransmitter release in vivo
eLife 9:e50345.
https://doi.org/10.7554/eLife.50345
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