Breathable and sweat tolerance PPy-leather dry electrode for long-term electroencephalogram monitoring

The commonly employed wet and semi-dry electroencephalogram (EEG) electrodes require the use of conductive media, resulting in issues such as reduced comfort, detached conductive coatings, and limitations in long-term wearing. In this study, we present a user-friendly dry EEG electrode made from conductive leather for long-term EEG monitoring. The conductive leather was obtained by in-situ synthesis of polypyrrole inside the goat leather, which could be further used as an EEG electrode. When positioned on the forehead, the interface impedance between the leather electrode and human skin complied with the international standard for EEG electrodes. The material's exceptional breathability enabled prolonged electrode wear. These leather electrodes facilitated precise monitoring of eye movement signals and α-wave activities in a relaxed state, laying the groundwork for extending their application to other brain regions. Furthermore, leather electrodes exhibited excellent performance even in the presence of sweat interference, thus confirming their advantages for long-term EEG monitoring. The leather dry electrode featuring superior wearability, portability, and long-term stability is expected to bring significant implications for future wearable technologies and monitoring devices.