INVITRO AND INVIVO ANALYSIS OF ANODIZED TANTALUM CAPACITIVE ELECTRODES - CORROSION RESPONSE, PHYSIOLOGY, AND HISTOLOGY

Oxidation-reduction reactions which can destroy high current-density metal-stimulating electrodes [for neural prosthesis in man] are avoided when using capacitive electrodes. The results of in vitro and in vivo testing of anodized, high surface area, sintered Ta electrodes were presented. The electrode corrosion response was excellent; there was no evidence of electrode dissolution. A deposit formed on the electrode surface, but had little effect on the voltage response to contant current stimulation. The physiological and histopathological results indicated the capacitive Ta electrode to be the safest yet tested.