Natural Polymers for Conductive Hydrogel in Electrocardiogram Applications

Abstract

This study investigates the development of conductive hydrogels from natural polymers, chitosan and sodium alginate, as sustainable alternatives to commercial ECG electrode gels. Designed to improve biocompatibility, adhesion, conductivity, and moisture retention, the hydrogels were characterized through pH measurement, conductivity testing, impedance analysis, and viscosity evaluation. Comparative results show that sodium alginate formulations, particularly SA Form 6, achieved pH levels close to commercial gels, exhibited high permittivity, and demonstrated stable capacitive behavior, while chitosan-based gels had lower pH and conductivity outside the optimal ECG range. Several formulations approached commercial standards in viscosity and dielectric properties, though conductivity requires further optimization for accurate signal transmission. These findings highlight sodium alginate as a promising, eco-friendly candidate for biomedical and wearable applications, with targeted improvements needed to maximize performance.