A Novel Wearable Flexible Dry Electrode Based on Cowhide for ECG Measurement.

Yiping Huang,Yuanwen Zou,Li Gou,Yatong Song

doi:10.3390/bios11040101

Abstract

The electrocardiogram (ECG) electrode, as a sensor, is an important part of the wearable ECG monitoring device. Natural leather is rarely used as the electrode substrate. In this paper, wearable flexible silver electrodes based on cowhide were prepared by sputtering and brush-painting. A signal generator, oscilloscope, impedance test instrument, and ECG monitor were used to build the test platform evaluating the performance of electrodes with six subjects. The lossless waveform transmission can be achieved with our electrodes. Therefore, the Pearson’s correlation coefficient calculated with input waveform and output waveform of the electrodes based on the top grain layer (GLE) and the split layer (SLE) of cowhide were 0.997 and 0.998 at 0.1 Hz respectively. The skin electrode impedance (Z) was tested, and the parameters of the equivalent circuit model of the skin electrode interface were calculated by a fitting method, indicating that the Z of the prepared electrodes was comparable with the standard gel electrode when the skin is moist enough. The signal-to-noise ratio of the ECG of the GLE and the SLE were 1.148 and 1.205 times that of the standard electrode in the standing posture, which meant the ECG measured by our electrodes was basically consistent with that measured by the standard electrode.

Highlights

Cardiovascular diseases (CVDs) are currently the leading cause of death globally [1]
Unlike the standard Ag/AgCl electrode, the physiological signal detection part is separated from the signal transmission part, which can reduce the impact of the transmission part on the contact between the detection part and the human body
TThhee EECCGG ooff ((aa))tthheessttaannddaarrddAAgg//AAggCCll eelleeccttrrooddee aanndd ((bb,cc)) tthhee eelleeccttrrooddeess bbaasseedd oonn tthhee ttoopp ggrraaiinn llaayyeerr aanndd sspplliitt lleaalyeyceetrrr..o((ddd)e) S(Sfiig)gntnhaaell--tetoole--ncntoorioissdeeerrabattaiiosoe(d(SSNoNnRR)t)hddeiiataoggprraagmmra..iTTnhhleaeyppeoorwwaenerrdss(ppgee)ccttthrrueummeleoocfftrtthohedeesstbtaaannsddeidinngognppotohsstetuusrpreeloitoffl(ae(ye)e)trht.heesstatannddaarrddAAgg//AAggCCll electrode (f) the electrode based on the top grain layer and (g) the electrode based on the split layer

Summary

Introduction

Cardiovascular diseases (CVDs) are currently the leading cause of death globally [1]. The ECG electrode is an important part of wearable ECG monitoring device, which can be divided into the standard Ag/AgCl electrode, micro-needle electrode, non-contact electrode and flexible dry electrode. The standard Ag/AgCl electrode with conductive gel is the most commonly used electrode for ECG measurement in clinic, which has some problems, such as limited shelf life, sensitization, and cumbersome skin treatment in use [9]. The polymeric micro-needle electrode made by Conor O’Mahony et al belongs to this category [10] He Zhang et al prepared a flexible micro-needle electrode based on PDMS to record ECG in daily life. It did not cause human discomfort, it still needed to puncture the skin surface [11]. The flexible capacitive ECG measurement electrode based on MEMS prepared by Long-Fei Wang et al [13] is such an electrode

Methods

Results

Conclusion