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Claw-shaped flexible and low-impedance conductive polymer electrodes for EEG recordings: Anemone dry electrode

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Abstract

Electroencephalogram (EEG) signals provide important brain information in healthcare settings. Wet electrodes have several limitations, including their time-consuming preparation and no long-term acquisition, and dry electrodes have become a promising candidate. However, dry electrodes face several challenges related to signal quality, comfort, conductivity and cost. This study aims to develop and evaluate a novel dry electrode for EEG recordings. The electrode material properties are characterized by electrochemical, mechanical force, and skin measurements. The electrode performance is evaluated by comparing the impedance, signal-to-noise ratio (SNR), and EEG signal features of the proposed electrode with those of a wet electrode and two commercial dry electrodes. The dry electrode design is based on the biological structure of the sea anemone and demonstrates an improved scalp fit and reduced signal noise and motion artifacts. The electrode materials include advanced conducting polymers combined with thermoplastic elastomers (TPEs) and carbon nanotubes (CNTs), which exhibit good electrical conductivity, mechanical properties, and safety. A low-cost injection molding fabrication method is proposed. The dry electrodes show a scalp contact impedance of 7 kΩ at 20 Hz, which is lower than that of wet and commercial dry electrodes. Resting-state EEG and event-related potential signals collected by the anemone dry electrode achieved more than 90% similarity with signals acquired by wet electrodes. Thus, a low-cost, comfortable anemone dry electrode that exhibits excellent EEG recording performance is presented. The anemone dry electrode represents an important technological advance in material and structural design for EEG recording sensors.

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Authors and Affiliations

  1. School of Life Science, Beijing Institute of Technology, Beijing, 100081, China

    ZhongYan Shi, Bo Jiang, ShiChao Liang, JiangTao Zhang, DingJie Suo, DuanDuan Chen, GuangYing Pei & TianYi Yan

  2. School of Medical Technology, Beijing Institute of Technology, Beijing, 100081, China

    JingLong Wu

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  1. ZhongYan Shi
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  2. Bo Jiang
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  7. DuanDuan Chen
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Correspondence to GuangYing Pei or TianYi Yan.

Additional information

This work was supported by the National Natural Science Foundation of China (Grant Nos. U20A20191, 82202291, 61727807, and 12104049).

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The supporting information is available online at https://tech.scichina.com and https://link.springer.com. The supporting materials are published as submitted, without typesetting or editing. The responsibility for scientific accuracy and content remains entirely with the authors.

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Shi, Z., Jiang, B., Liang, S. et al. Claw-shaped flexible and low-impedance conductive polymer electrodes for EEG recordings: Anemone dry electrode. Sci. China Technol. Sci. 66, 255–266 (2023). https://doi.org/10.1007/s11431-022-2231-3

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  • DOI: https://doi.org/10.1007/s11431-022-2231-3

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