Charge storage: stability measures in implantable electrodes.
Here we report on long-term (300 to 600 hours) stability measures for implantable stimulating electrodes. We have considered several measures of stability as they refer to reliability of charge carrying capacity in implantable electrodes. We have designed and manufactured coatings for large area (1 to 2mm(2)) stainless steel substrates. Materials tested were electrodeposited iridium oxide films, multi-walled carbon nanotube mesh, and PEDOT:PSS. Traditional characterization techniques such as cyclic voltammetry and electrochemical impedance spectroscopy cover a small fraction of the characterization framework needed for ensuring the safety and performance of electrodes designed for long-term implants. The stability measures suggested here rely on continuous low frequency cycling and evaluation of cathodic charge storage capacity during cycling. We experimentally show, in this paper, that the stability may be measured and is relevant for long-term applications of such coatings.
Peixoto
Nathalia
N
Electrical and Computer Engineering Department of George Mason University; 4400 University Drive, MS1G5, Fairfax VA 22030 USA. npeixoto@gmu.edu
Jackson
Kassandra
K
Samiyi
Raamin
R
Minnikanti
Saugandhika
S
D000818:Animals; D004553:Electric Conductivity; D004567:Electrodes, Implanted; D004867:Equipment Design; D019544:Equipment Failure Analysis; D051381:Rats; D017207:Rats, Sprague-Dawley; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D055672:Static Electricity