Magnetic Manipulation of Locomotive Liquid Electrodes for Wireless Active Cardiac Monitoring

Abstract

For electrocardiogram (ECG) detection, the position ofconventionalpatch-type electrodes based on solid-state metals are difficult tomanipulate after attachment and also can lead to poor interface withstretchable, rough skin surfaces. Herein, we present a liquid formof ECG electrodes that can be magnetically reconfigured on human skinby providing its conformal interfacing. These electrodes consist ofbiocompatible liquid-metal droplets where magnetic particles are homogeneouslydispersed, and their conformal contact with skin can yield significantlylow impedance as well as high signal-to-noise ratio of ECG peaks.These electrodes are also capable of complex motions such as linearmovements, splitting, and merging under external magnetic fields.Furthermore, magnetic manipulation of each electrode position on humanskin enables precise monitoring of ECG signals with the change inECG vectors. The integration of liquid-state electrodes with electroniccircuitry demonstrates wireless and continuous ECG monitoring whilemagnetically moving this entire system on human skin.