Department of Materials Science and Engineering, National University of Singapore, Singapore 117574.
Department of Electrical and Computer Engineering, National University of Singapore, Singapore 117574.
ACS Appl Mater Interfaces. 2022 Aug 31;14(34):39159-39171. doi: 10.1021/acsami.2c11921. Epub 2022 Aug 16.
Dry epidermal electrodes that can always form conformal contact with skin can be used for continuous long-term biopotential monitoring, which can provide vital information for disease diagnosis and rehabilitation. But, this application has been limited by the poor contact of dry electrodes on wet skin. Herein, we report a biocompatible fully organic dry electrode that can form conformal contact with both dry and wet skin even during physical movement. The dry electrodes are prepared by drop casting an aqueous solution consisting of poly(3,4-ethylenedioxythiophene):polystyrenesulfonate (PEDOT:PSS), poly(vinyl alcohol) (PVA), tannic acid (TA), and ethylene glycol (EG). The electrodes can exhibit a conductivity of 122 S cm and a mechanical stretchability of 54%. Moreover, they are self-adhesive to not only dry skin but also wet skin. As a result, they can exhibit a lower contact impedance to skin than commercial Ag/AgCl gel electrodes on both dry and sweat skins. They can be used as dry epidermal electrodes to accurately detect biopotential signals including electrocardiogram (ECG) and electromyogram (EMG) on both dry and wet skins for the users at rest or during physical movement. This is the first time to demonstrate dry epidermal electrodes self-adhesive to wet skin for accurate biopotential detection.
能够始终与皮肤形成贴合接触的干性表皮电极可用于连续的长期生物电位监测，这可为疾病诊断和康复提供重要信息。但是，这种应用受到干性电极在湿皮肤上接触不良的限制。在此，我们报告了一种具有生物相容性的全有机干性电极，即使在身体运动时，它也能与干燥和湿润的皮肤形成贴合接触。干性电极是通过滴铸由聚（3,4-亚乙基二氧噻吩）：聚苯乙烯磺酸（PEDOT：PSS）、聚乙烯醇（PVA）、鞣酸（TA）和乙二醇（EG）组成的水溶液制备而成。这些电极的电导率可达 122 S cm，机械拉伸率可达 54%。此外，它们不仅对干燥皮肤，而且对湿润皮肤都具有自粘性。因此，与商用 Ag/AgCl 凝胶电极相比，它们在干燥和出汗皮肤上的接触阻抗均较低。它们可用作干性表皮电极，可在静止或运动时准确检测包括心电图（ECG）和肌电图（EMG）在内的生物电位信号，适用于干性和湿性皮肤的使用者。这是首次证明对湿皮肤具有自粘性的干性表皮电极可用于准确的生物电位检测。
