Electrocardiogram Patch to Monitor Full-Day Activities for Multiple Days

The heart regularly makes electrical signals, and these signals drive the heartbeat. Heartbeat abnormalities (ex. arrhythmias) can be diagnosed through Electrocardiogram (ECG) measurement. Existing ECG devices including Halter-type devices have some problems with electrode properties for stable and long-term measurement. Recently, many patch-type stretchable electrodes have been developed to solve this problem. Electrolyte gel, a representative ECG electrode, causes problems such as skin rashes when used for a long period of time and is difficult to use in a humid environment. Therefore, we propose a full-day wearable ECG sensor that can be used to measure ECG during various daily activities such as exercising, showering and sleeping. A porous stretchable material substrate is produced by electrospinning a biocompatible polymer, and it can be easily fabricated as a sensor through simple Au sputtering. In addition, the simple surface treatment and the porous double layer structure induces quick evaporation of sweat along with water proofing to prevent skin rashes. The fabricated sensor showed constant resistance change under biaxial strain of 1000 cycles. Also, when it was attached to a human for 3 days, it was possible to measure the ECG stably even in the state of sleeping, exercising, and showering.