Progress on Fabric Electrodes Used in Biological Signal Acquisition

Due to its convenience, wear ability, affinity, continuously monitoring biological signal, etc., fabric electrodes used in biological signal acquisition attracted more and more interest from researchers around the world. Fabric electrode is a kind of intelligent textiles, and its application is very prominent in biological signal acquisition, supercapacitors and ECG (electric signal) monitoring. There are many methods that can be used to prepare fabric electrodes. They are mainly metal plating, conductive polymer coating, magnetron sputtering, and gas phase deposition and impregnation. Besides, they select the appropriate substrate, conductive medium and composite way to get light fabric electrodes which have high conductivity and good conformability. Since the conductive properties of conductive polymers are weaker than those of metal, conductive polymer must undergo protonic acid doping. They can be polythiophene, polypyrrole, polyaniline, etc. However, at present, researchers commit more studies to metal or carbon-based electrodes. For example, a layer of silver film is platted on the fabric by magnetron sputtering to increase its conductivity. In this paper, the development of fabric electrodes was studied from several aspects, namely, the generation of biological signals, the overall design of the wearable monitoring systems, its classification, conductive principles, preparation of fabric electrode and application.