Characterizing Longitudinal Changes in the Impedance Spectra of In-Vivo Peripheral Nerve Electrodes.

ABSTRACT: Characterizing the aging processes of electrodes in vivo is essential in order to elucidate the changes of the electrode⁻tissue interface and the device. However, commonly used impedance measurements at 1 kHz are insufficient for determining electrode viability, with measurements being prone to false positives. We implanted cohorts of five iridium oxide (IrOx) and six platinum (Pt) Utah arrays into the sciatic nerve of rats, and collected the electrochemical impedance spectroscopy (EIS) up to 12 weeks or until array failure. We developed a method to classify the shapes of the magnitude and phase spectra, and correlated the classifications to circuit models and electrochemical processes at the interface likely responsible. We found categories of EIS characteristic of iridium oxide tip metal

SUBMITTER: Straka MM 

PROVIDER: S-EPMC6266965 | biostudies-literature | 2018 Nov

REPOSITORIES: biostudies-literature