Structurally Stable Bilayer Hydrogel Interfaces Enabling High-Fidelity Electrophysiological Signal Monitoring under...

Area of Science:

• Biomedical Engineering
• Materials Science
• Electrophysiology

Background:

• Epidermal electrodes are crucial for long-term, high-fidelity electrophysiological monitoring.
• Current electrodes often lack structural integrity under mechanical stress, limiting their use.
• Need for robust electrodes that maintain performance during daily activities and extreme conditions.

Purpose of the Study:

• To engineer a mechanically resilient and conductive bilayer hydrogel (BLH) electrode.
• To achieve robust integration with a bacterial cellulose (BC) stress carrier for enhanced durability.
• To enable reliable long-term electrophysiological signal acquisition in complex motion scenarios.

Main Methods:

• Rapid in situ gelation (94 s) for BLH electrode fabrication.
• Utilizing liquid metal droplets to catalyze polymerization and ensure interfacial coupling.
• Integrating the BLH electrode with a rigid bacterial cellulose stress carrier.
• Finite element analysis to validate stress dispersion and mechanical resilience.

Main Results:

• The BLH electrode demonstrated robust mechanical properties and sustained durability.
• Stable performance was maintained after 50,000 bending cycles and 3000 impacts.
• Achieved reliable long-term signal acquisition with a signal-to-noise ratio (SNR) of approximately 16.1 dB.
• The architecture effectively mitigated structural degradation and performance deterioration under stress.

Conclusions:

• The developed BLH electrode offers a mechanically stable and highly integrated solution for electrophysiological monitoring.
• The stress-prioritized architecture enhances durability and performance under mechanical stress.
• This strategy provides a transformative approach for advanced hydrogel electrode development in demanding applications.