Effects of Geometry on Performances of Optically Unobtrusive Zeolite-Based Electrodes

Long-term monitoring of vital signs is a paramount aspect of evaluating sporadic cardiac dysfunctions, which are difficult to assess in short clinical sessions. Electrocardiogram (ECG) monitoring during daily activities (walking or exercising) is desirable from the clinical point of view to detect anomalies. Optically unobtrusive electrodes facilitate the ubiquitous acquisition of health data. A zeolite-based dry electrode was investigated as a long-term sensor with high transparency. Electrodes fabricated with two different zeolites (4A degrees and 13X), different thicknesses, and surfaces were analyzed to evaluate electrical characteristics and the Signal-to-Noise (SNR) on ECG acquisitions. Zeolite 4A degrees evidenced a higher SNR, up to 37.5 dB, compared to Zeolite 13X electrodes with an SNR of 35.2 dB, having a concentration of 4 w/w%. Increasing the diameter from 20 to 30 mm results in an enhancement of 7.8% of SNR. A 12% improvement in SNR is reported when the thickness of the electrode is decreased by 50%, showing that a decrease in thickness of the electrode contributes to the advancement of SNR.

Automated summary

Long-term monitoring of vital signs is crucial for evaluating sporadic cardiac dysfunctions, and optically unobtrusive electrodes offer advantages of high transparency and ubiquitous health data acquisition. The study found that electrodes fabricated with zeolite 4A degrees exhibited a higher Signal-to-Noise Ratio (SNR), and increasing the diameter and decreasing the thickness of the electrode contributed to the improvement of SNR.