journal article·2025-12-31Open access

Flexible Conductive Paper-Based Sensors for On-Skin Electrophysiological Monitoring and Wearable Applications

George Al Boustani, Lukas Bichlmaier, Tetsuhiko F. Teshima, Oleksandr Berezin, Lennart JK Weiß, Koji Sakai, Kenji Kondo, Lukas Hiendlmeier, Defne Tüzün, Beatrice De Chiara, Marta Nikić, Gil G Westmeyer, Shigeyoshi Inoue, Markus Becherer, Bernhard Wolfrum

Abstract

Flexible, skin-conformable electrodes require materials that combine mechanical robustness, environmental stability, high electrical performance, and biocompatibility. Here, we present a flexible conductive composite film composed of poly(3,4-ethylenedioxythiophene):polystyrenesulfonate (PEDOT:PSS), cellulose nanofibers (CNF), and the ionic liquid 1-ethyl-3-methylimidazolium ethyl sulfate (EMIM ES). The composite is fabricated via a simple aqueous blending and filtration process, yielding a free-standing film with a robust fibrous microstructure. ATR-FTIR analysis confirms the successful integration of all components, while SEM imaging reveals a percolated nanofibrillar architecture that enhances interfacial adhesion and structural integrity. Mechanical testing reveals a tensile strength of up to 335 MPa, accompanied by a strain of 21%, attributed to the increasing CNF content. Composite films with low CNF content exhibit excellent electrical stability across humidity levels between 10% and 90% and temperatures of 15-55 °C, and maintain electrochemical performance after 100,000 cycles of mechanical fatigue testing. On-skin electrophysiological recordings from a rodent model demonstrate stable signal acquisition without skin irritation, establishing the hybrid films as a promising platform for soft, wearable bioelectronic interfaces.
Source: openalex_inverted_index · Quality: baseline

Research context

OpenAlex topics: Advanced Sensor and Energy Harvesting Materials · Nanomaterials and Printing Technologies · Conducting polymers and applications

SciVX discovery tags are terminology-based. OpenAlex topics are source-provided classifications.

Affiliations

Neuroelectronics, Munich Institute of Biomedical Engineering, Department of Electrical Engineering, TUM School of Computation, Information and Technology

Technical University of Munich

Medical & Health Informatics Laboratories

NTT Research Incorporated

Chair of Silicon Chemistry, Department of Chemistry, Institute of Silicon Chemistry and Catalysis Research Center, TUM School of Natural Sciences

Faculty of Science and Technology, Keio University, Yokohama, 108-0073 Kanagawa 223−8522, Japan

Munich Institute of Biomedical Engineering, TUM School of Natural Sciences & TUM School of Medicine and Health

Neurobiological Engineering

NTT Basic Research Laboratories and Bio-Medical Informatics Research Center, NTT Corporation, 3-1, Morinosato Wakamiya, Atsugi, Kanagawa 243-0198, Japan

New Materials Development Team, Wet-Jet Mill Technical Department, Plant Equipment Division, Sugino Machine Limited, 2880 Kuriyama, Namerikawa, Toyama 936-8577, Japan

Chip-Based Magnetic Sensor Technology, ZEITlab TUM School of Computation, Information and Technology

Funding

Federal Ministry of Research, Technology and Space · Free State of Bavaria · Länder

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