A comparison of fabrication methods for Iridium Oxide reference electrodes

Several methods for the manufacturing of Iridium Oxide (IrOx) electrodes have been discussed in the literature. Two commonly used fabrication methods are Sputtered Iridium Oxide Films (SIROF) and Activated Iridium Oxide Films (AIROF). Most of the studies for in vivo electrodes have reported optimizations to these methods in the context of stimulation of and recording from neural tissue. In this work we characterize three fabrication methods of IrOx films for use as reference electrodes during in vivo neurochemical recordings, and we conclude that AIROF electrodes are preferable as reference electrodes due to their superior open circuit potential (OCP) stability.