Skin stimulation and recording: Moving towards metal-free electrodes
Journal article, 2022
When one thinks about electrodes, especially ones meant for humans, one typically thinks of some kind of metal. Whether on the skin or in the brain, metal electrodes are characteristically expensive, stiff, non-efficient in electron-ion transduction, and prone to toxic metal ion by-products during stimulation. In order to circumvent these disadvantages, electrically-conductive laser-induced graphene (LIG) and mixed electron-ion conducting polymer (poly(3, 4‐ethylenedioxythiophene) polystyrene sulfonate – PEDOT:PSS) was leveraged to create a metal-free electrode combination that allows for an economical, soft, and organic electrode for applications on human skin. Compared to clinical-standard silver – silver chloride (Ag/AgCl) skin electrodes, the metal-free hydrogel electrodes show notable improvement in electrochemical stability and prolonged stable potentials during long-term DC stimulation (0.5–24 h). Recording and stimulation performance on human participants rivals that of Ag/AgCl, thus fortifying the notion that they are an appropriate progression to their noble metal counterparts.
Direct current stimulation
Bioelectronics
Conducting hydrogels
Skin electrodes
Author
Sebastian W. Shaner
University of Freiburg
Monsur Islam
Karlsruhe Institute of Technology (KIT)
Morten B. Kristoffersen
Center for Bionics and Pain Research
Sahlgrenska University Hospital
Raheleh Azmi
Karlsruhe Institute of Technology (KIT)
Stefan Heissler
Karlsruhe Institute of Technology (KIT)
Max Jair Ortiz Catalan
Center for Bionics and Pain Research
Sahlgrenska University Hospital
Chalmers, Electrical Engineering, Systems and control
Jan G. Korvink
Karlsruhe Institute of Technology (KIT)
Maria Asplund
University of Freiburg
Luleå University of Technology
Biosensors and Bioelectronics: X
25901370 (eISSN)
Vol. 11 100143Subject Categories (SSIF 2011)
Inorganic Chemistry
Analytical Chemistry
Materials Chemistry
DOI
10.1016/j.biosx.2022.100143