Flexible and robust dry electrodes based on electroconductive polymer spray-coated 3D porous graphene for long-term electrocardiogram signal monitoring system

This study developed highly flexible and conductive dry electrodes using a biocompatible polymer (PEDOT:PSS) loaded on mechanically robust laser-induced graphene (LIG). These electrodes are designed for long-term, comfortable electrocardiogram (ECG) signal monitoring with fewer motion artifacts compared to conventional wet electrodes.

• Development of flexible, robust, and highly conductive dry electrodes.
• Use of PEDOT:PSS spray-coated on laser-induced graphene (LIG).
• Achieved low skin-contact impedance and high signal-to-noise ratio (SNR) comparable to wet Ag/AgCl electrodes.
• Demonstrated successful long-term ECG monitoring with reduced motion artifacts.

Circular LIG electrodes were patterned using a CO₂ laser and then spray-coated with PEDOT:PSS to enhance conductivity and robustness. The electrodes were characterized using FESEM, XPS, XRD, and Raman Spectra. Skin-contact impedance was measured, and ECG signal quality was compared to standard Ag/AgCl electrodes during rest and movement.

The electrodes showed low surface resistivity (17.4 Ω/sq) and skin contact impedance (385 kΩ at 10 Hz). The ECG signal's SNR (12.9 dB) was comparable to Ag/AgCl electrodes (13.3 dB). The electrodes demonstrated stable, long-term monitoring with fewer motion artifacts, and the data was successfully transmitted to a mobile app.