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Research Article | Online first | Published: 22 March 2024

An injectable, self-healable, and reusable PEDOT:PSS/PVA hydrogel patch electrode for epidermal electronics

Show Author's Information Yang Li1,2,§( ),  Yuzhe Gu1,§,  Sheng Qian2,  Shuwen Zheng1,  Yuncong Pang2,  Lele Wang1,  Baoguang Liu1,  Shujuan Liu2( ),  Qiang Zhao1,2( )
College of Electronic and Optical Engineering and College of Flexible Electronics (Future Technology), Nanjing University of Posts and Telecommunications (NJUPT), Nanjing 210023, China
State Key Laboratory of Organic Electronics and Information Displays and Jiangsu Key Laboratory for Biosensors, Institute of Advanced Materials (IAM), Nanjing University of Posts and Telecommunications (NJUPT), Nanjing 210023, China

§ Yang Li and Yuzhe Gu contributed equally to this work.

Keywords:
self-healing, injectability, brain–computer interface, electrophysiological recording, epidermal hydrogel electrodes, reusability
Topics:
ElectrophysiologyGelsMedical applicationsOrganic semiconductor materialsSignal detectionWearable technology
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Li Y, Gu Y, Qian S, et al. An injectable, self-healable, and reusable PEDOT:PSS/PVA hydrogel patch electrode for epidermal electronics. Nano Research, 2024, https://doi.org/10.1007/s12274-024-6515-7
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Abstract Full text Electronic supplementary material About this article

Injectability empowers conductive hydrogels to transcend traditional limitations, unlocking a realm of possibilities for innovative medical, wearable, and therapeutic applications that can significantly enhance patient care and quality of life. Here, we report an injectable, self-healable, and reusable hydrogel obtained by mixing the concentrated poly(3,4-ethylenedioxythiophene) doped with polystyrene sulfonate (PEDOT:PSS) suspension (~ 2 wt.% solid content), polyvinyl alcohol (PVA), and borax. Leveraging the presence of reversible borax/hydroxyl bonds and multiple hydrogen bonds, this PEDOT:PSS/PVA hydrogel exhibits notable shear-thinning behavior and self-healing capabilities, enabling it to be injected as a gel fiber from a syringe. As-prepared injectable hydrogel also demonstrates an ultra-low modulus (~ 2.5 MPa), reduced on-skin impedance (~ 45% of commercial electrodes), and high signal-to-noise ratio (SNR) (~ 15–22 dB) in recording of electrocardiography (ECG), electromyography (EMG), and electroencephalogram (EEG) signals. Furthermore, the injectable hydrogels can be remolded and reinjected as the reusable electrodes, maintaining nearly identical electrophysiological recording capabilities and brain–computer interface (BCI) performance compared to commercial wet electrodes. With their straightforward fabrication, excellent material properties and electronic performance, ease of cleaning, and remarkable reusability, our injectable PEDOT:PSS/PVA hydrogels hold promise for advancements in BCI based electronics and wearable bioelectronics.


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Electronic supplementary material
About this article

An injectable, self-healable, and reusable PEDOT:PSS/PVA hydrogel patch electrode for epidermal electronics

Show Author's information Yang Li1,2,§( ), Yuzhe Gu1,§, Sheng Qian2, Shuwen Zheng1, Yuncong Pang2, Lele Wang1, Baoguang Liu1, Shujuan Liu2( ), Qiang Zhao1,2( )
College of Electronic and Optical Engineering and College of Flexible Electronics (Future Technology), Nanjing University of Posts and Telecommunications (NJUPT), Nanjing 210023, China
State Key Laboratory of Organic Electronics and Information Displays and Jiangsu Key Laboratory for Biosensors, Institute of Advanced Materials (IAM), Nanjing University of Posts and Telecommunications (NJUPT), Nanjing 210023, China

§ Yang Li and Yuzhe Gu contributed equally to this work.

Abstract

Injectability empowers conductive hydrogels to transcend traditional limitations, unlocking a realm of possibilities for innovative medical, wearable, and therapeutic applications that can significantly enhance patient care and quality of life. Here, we report an injectable, self-healable, and reusable hydrogel obtained by mixing the concentrated poly(3,4-ethylenedioxythiophene) doped with polystyrene sulfonate (PEDOT:PSS) suspension (~ 2 wt.% solid content), polyvinyl alcohol (PVA), and borax. Leveraging the presence of reversible borax/hydroxyl bonds and multiple hydrogen bonds, this PEDOT:PSS/PVA hydrogel exhibits notable shear-thinning behavior and self-healing capabilities, enabling it to be injected as a gel fiber from a syringe. As-prepared injectable hydrogel also demonstrates an ultra-low modulus (~ 2.5 MPa), reduced on-skin impedance (~ 45% of commercial electrodes), and high signal-to-noise ratio (SNR) (~ 15–22 dB) in recording of electrocardiography (ECG), electromyography (EMG), and electroencephalogram (EEG) signals. Furthermore, the injectable hydrogels can be remolded and reinjected as the reusable electrodes, maintaining nearly identical electrophysiological recording capabilities and brain–computer interface (BCI) performance compared to commercial wet electrodes. With their straightforward fabrication, excellent material properties and electronic performance, ease of cleaning, and remarkable reusability, our injectable PEDOT:PSS/PVA hydrogels hold promise for advancements in BCI based electronics and wearable bioelectronics.

Keywords: self-healing, injectability, brain–computer interface, electrophysiological recording, epidermal hydrogel electrodes, reusability

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Publication history
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Acknowledgements

Publication history

Received: 14 December 2023
Revised: 25 January 2024
Accepted: 25 January 2024
Published: 22 March 2024

Copyright

© Tsinghua University Press 2024

Acknowledgements

Acknowledgements

This work was financially supported by the National Natural Science Foundation of China (Nos. 62304112 and 62288102), Natural Science Foundation of Jiangsu Province of China (No. BK20230359), Natural Science Foundation of the Higher Education Institutions of Jiangsu Province (No. 22KJB430038), and Natural Science Research Start-up Foundation of Recruiting Talents of Nanjing University of Posts and Telecommunications (No. NY221111).

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