*** 96-60054 Twardoch Iridium oxide is becoming the material of choice for electrodes in functional electrical stimulation (FES) because of its corrosion resistance, low impedance, and high charge injection capacity. Use of Ir metal electrodes which can be anodized, however, is not always possible. Alternative deposition methods of Ir oxide films such as sputtering or thermal decomposition of Ir precursors are unacceptable for many of the complex and thermally sensitive devices such as cochlear implants and neural cuffs. The objective of this research is to develop a process for electrodepositing Ir oxide at temperatures below 100 C to produce conformal coatings. Manufactured electrodes for a variety of FES applications can be "retrofitted" with the coatings, or the coating procedure can be integrated into the production process. The Phase I project will investigate both electroplating of thin, nonporous Ir followed by anodic "activation" and direct deposition of Ir oxide. Advanced tools for optimizing electrodeposition protocols will be employed, including computer-controlled potentiostatic waveforms and the electrochemical quartz crystal nanobalance. The physical properties of the coatings will be evaluated as well as their suitability as stimulating electrodes. The methods producing the best quality films will be used in the next phase to coat electrodes currently used in FES research and commercial products. The proferred significant improvement in the technology of electroactive prosthetic devices will be used in commercial medical electrodes for treatment of neural functional impairment such as hearing loss, incontinence, sexual dysfunction, limb paralysis, and spasticity and in equipment for coating electrodes. ***
