Organic electrochemical transistor arrays for real-time mapping of evoked neurotransmitter release in vivo

  1. Kai Xie
  2. Naixiang Wang
  3. Xudong Lin
  4. Zixun Wang
  5. Xi Zhao
  6. Peilin Fang
  7. Haibing Yue
  8. Junhwi Kim
  9. Jing Luo
  10. Shaoyang Cui
  11. Feng Yan  Is a corresponding author
  12. Peng Shi  Is a corresponding author
  1. City University of Hong Kong, China
  2. The Hong Kong Polytechnic University, Hong Kong
  3. City University of Hong Kong, Hong Kong
  4. Shenzhen Hospital of Guangzhou University of Chinese Medicine, China

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

  1. Kai Xie

    Department of Biomedical Engineering, City University of Hong Kong, Kowloon, China
    Competing interests
    The authors declare that no competing interests exist.
  2. Naixiang Wang

    Department of Applied Physics, The Hong Kong Polytechnic University, Hong Kong, Hong Kong
    Competing interests
    The authors declare that no competing interests exist.
  3. Xudong Lin

    Department of Biomedical Engineering, City University of Hong Kong, Kowloon, Hong Kong
    Competing interests
    The authors declare that no competing interests exist.
  4. Zixun Wang

    Department of Biomedical Engineering, City University of Hong Kong, Kowloon, Hong Kong
    Competing interests
    The authors declare that no competing interests exist.
  5. Xi Zhao

    Department of Biomedical Engineering, City University of Hong Kong, Kowloon, Hong Kong
    Competing interests
    The authors declare that no competing interests exist.
  6. Peilin Fang

    Department of Biomedical Engineering, City University of Hong Kong, Kowloon, Hong Kong
    Competing interests
    The authors declare that no competing interests exist.
  7. Haibing Yue

    Department of Biomedical Engineering, City University of Hong Kong, Kowloon, Hong Kong
    Competing interests
    The authors declare that no competing interests exist.
  8. Junhwi Kim

    Department of Biomedical Engineering, City University of Hong Kong, Kowloon, Hong Kong
    Competing interests
    The authors declare that no competing interests exist.
  9. Jing Luo

    Department of Rehabilitation, Shenzhen Hospital of Guangzhou University of Chinese Medicine, Shenzhen, China
    Competing interests
    The authors declare that no competing interests exist.
  10. Shaoyang Cui

    Department of Rehabilitation, Shenzhen Hospital of Guangzhou University of Chinese Medicine, Shenzhen, China
    Competing interests
    The authors declare that no competing interests exist.
  11. Feng Yan

    Department of Applied Physics, The Hong Kong Polytechnic University, Hong Kong, Hong Kong
    For correspondence
    apafyan@polyu.edu.hk
    Competing interests
    The authors declare that no competing interests exist.
  12. Peng Shi

    Department of Biomedical Engineering, City University of Hong Kong, Kowloon, Hong Kong
    For correspondence
    pengshi@cityu.edu.hk
    Competing interests
    The authors declare that no competing interests exist.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0003-0629-4161

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.

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.

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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  1. Kai Xie
  2. Naixiang Wang
  3. Xudong Lin
  4. Zixun Wang
  5. Xi Zhao
  6. Peilin Fang
  7. Haibing Yue
  8. Junhwi Kim
  9. Jing Luo
  10. Shaoyang Cui
  11. Feng Yan
  12. Peng Shi
(2020)
Organic electrochemical transistor arrays for real-time mapping of evoked neurotransmitter release in vivo
eLife 9:e50345.
https://doi.org/10.7554/eLife.50345

Share this article

https://doi.org/10.7554/eLife.50345

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