Flexible Multichannel Neural Probe Developed by Electropolymerization for Localized Stimulation and Sensing

Research output: Journal Publications and Reviews (RGC: 21, 22, 62)21_Publication in refereed journalpeer-review

1 Scopus Citations
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Author(s)

  • Gary Kwok Ki Chik
  • Xudong Ji
  • Anderson Chun On Tsang
  • Gilberto Ka Kit Leung
  • Shiming Zhang
  • Paddy Kwok Leung Chan

Related Research Unit(s)

Detail(s)

Original languageEnglish
Article number2200143
Journal / PublicationAdvanced Materials Technologies
Volume7
Issue number8
Online published1 Apr 2022
Publication statusPublished - Aug 2022

Abstract

Miniaturization and minimization of mechanical mismatch in neural probes have been two well-proven directions in suppressing immune response and improving spatial resolution for neuronal stimulations and recordings. While the high impedance brought by the miniaturization of electrodes has been addressed by using conductive polymers coatings in multiple reports, the stiffness of such coatings remains orders of magnitude higher than that of the brain tissue. Here, a flat neural probe based on a highly flexible microelectrode array with electrodeposited hydrogel coatings poly(2-hydroxyethyl methacrylate) (pHEMA) and conductive polymer poly(3,4-ethylenedioxythiophene) polystyrene sulfonate (PEDOT/PSS), with a cross-section area at only 300 µm × 2.5 µm is presented. The PEDOT/PSS coating provides a low interfacial impedance, and the pHEMA deposition bridges the mechanical mismatch between the probe and the brain tissues. The two layers of polymers modification enhance the signal-to-noise ratio and allow the microelectrodes array to be engineered for both recording and stimulation purposes. Besides, in vivo testing of microelectrode arrays implanted in rat hippocampus confirms a high senstivity in neural signal recording and excellent charge injection capacity which can induce long-term potentiation in neural activities in the hippocampus. The probes provide a robust and low-cost solution to the brain interfaces problem.

Research Area(s)

  • bioelectronics, electropolymerization, hydrogel, neural probe, neuronal stimulation

Citation Format(s)

Flexible Multichannel Neural Probe Developed by Electropolymerization for Localized Stimulation and Sensing. / Chik, Gary Kwok Ki; Xiao, Na; Ji, Xudong et al.

In: Advanced Materials Technologies, Vol. 7, No. 8, 2200143, 08.2022.

Research output: Journal Publications and Reviews (RGC: 21, 22, 62)21_Publication in refereed journalpeer-review