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ABSTRACT Wearable electroencephalography (EEG) devices offer a promising solution for continuous brain monitoring outside laboratory settings. However, maintaining stable signal quality over extended periods remains challenging, as skin‐mounted EEG systems are prone to contact‐induced noise caused by skin deformation and body motion. Here, we present a wrinkle‐adaptive kirigami structure and a soft, wearable EEG patch engineered to match subject‐specific forehead wrinkle patterns, thereby stabilizing the electrode‐skin interface. Our two‐step kirigami architecture integrates global conformability with localized strain accommodation, delivering anisotropic deformability and maintaining mechanical stability during facial motion. Leveraging an automated image‐based workflow, we enable scalable, individualized generation of kirigami patterns. When integrated into a soft, wireless wearable system, the personalized patch delivers consistently enhanced signal‐to‐noise ratios across multiple EEG frequency bands, even under diverse motion conditions in at‐home sleep settings. This technology demonstrates broad applicability for sleep EEG monitoring and underscores the potential of morphology‐aware structural design for next‐generation wearable EEG devices.
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This content will become publicly available on June 23, 2027
Self‐Maintaining Electrode–Skin Interface for Motion‐Robust Biosignal Monitoring
ABSTRACT The electrode–skin interface presents a fundamental challenge in bioelectronics: maintaining stable electrical contact with tissue that undergoes constant physiological changes. Here we demonstrate a paradigm shift by engineering a self‐sustaining microenvironment at the skin–electrode interface through the integration of Au‐coated fabric electrodes with a humidity‐regulating cooling patch. Our smart electrode‐integrated cooling (SEIC) patch uses evaporative cooling to create a humid microenvironment where water condensation continuously regenerates ionic pathways between skin and electrode. This transforms the interface from a static contact point to a dynamic, self‐renewing electrochemical junction. The SEIC patch exhibits 200‐fold and 10‐fold lower impedances than Au‐coated fabric electrodes and conventional electrodes, respectively; maintains performance through 2000 attachment cycles; enables stable biosignal acquisition for eight days; and preserves signal fidelity under motion. Moreover, the SEIC demonstrates applications in continuous cardiac monitoring during daily life, and real‐time 3D facial animation reconstruction in virtual reality via high‐fidelity capture of facial muscle activity. This work opens new frontiers in preventive medicine and human–computer interaction.
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- Award ID(s):
- 2403528
- PAR ID:
- 10700533
- Editor(s):
- Goebel, Uta; Bandyopadhyay, Debarati; Gannon, Alanna
- Publisher / Repository:
- Wiley Advances
- Date Published:
- Journal Name:
- Advanced Healthcare Materials
- ISSN:
- 2192-2640
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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