Highly precise nanofiber web-based dry electrodes for vital signal monitoring†
A great variety of dry electrodes have been developed over many decades in order to overcome the drawbacks of conventional Ag/AgCl gel electrodes, but their applications are still restricted due to the low accuracy of the dry electrodes. To improve their accuracy, highly elastic thermoplastic polyurethane (TPU) and poly(styrene-b-butadiene-b-styrene) (SBS) were electrospun into nanofiber webs containing Ag nanoparticles. Then, these webs were silver plated using electroless plating to prepare silver plated nanofiber web (AgNFw)-based dry electrodes that allowed for the detection of high fidelity biopotential signals. The electrode properties of AgNFw dry electrodes were investigated thoroughly using agar phantom systems. Human subject tests were also carried out to determine the real performance of AgNFw dry electrodes on a human body in terms of biopotential recording and electrical impedance tomography (EIT) measurements. The experimental results revealed that AgNFw dry electrodes can exhibit performances comparable to Ag/AgCl gel electrodes, indicating the newly designed AgNFw dry electrodes have superior accuracy to most existing dry electrodes.