PEDOT: PSS Hydrogel based Flexible Electrodes for Wearable ECG Monitoring

Abstract

Wearable devices for health monitoring like electrocardiography(ECG) use commercial Ag/AgCl electrodes to detect signals, but they can cause skin irrtation and lead unreliable data during prolonged usage. This work shows alternative ECG electrodes, we obtained these electrodes using Poly(3,4-ethylenedioxythiophene):poly(styrenesulfonate) (PE-DOT:PSS) hydrogel and commercially flexible materials. 4-dodecylbenzenesulfonic acid (DBSA) could increase the conductivity of PEDOT:PSS and make the formation of hydrogel in commerically flexible materials at a short time. We validated the impedance and ECG signlas of these flexible electrodes, and found the optimized one(wound dressing) compared to commercial electrode and got the equivalent circuit model of it. Furthermore, we designed the ECG flexible printed circuit matching the optimized electrode to form a patch, and used the patch as wearable device to detect the ECG signals of volunteer in static condition and got the variation of heart rate value in dynamic condition. The interface impedance of our ECG electrode was small compared to commercial electrodes and the ECG signals were similar with them. The results of on-body testing shown our electrode with FPC could work as wearable devices for health monitoring in both static and dynamic conditions. These results suggest that our electrode could be alternated commercial electrode due to its high conductivity, biocompatibility, flexibility, recyclability and low price.