Platinum stimulating electrodes in physiological media.

The study reported here seeks to characterize behaviour of platinum electrodes of the 45-electrode spiral nerve cuff for selective electrical stimulation of different superficial regions of peripheral nerves in physiological solution (0.9% NaCl) and Eliott's buffered solution. Each electrode of the spiral cuff had a flat geometric surface of 2 mm2. To delineate an operational potential window between hydrogen and oxygen evolution during stimulation the electrochemical technique of cyclic voltammetry was used. In a typical cyclic voltammetry experiment, the potential of the tested electrode was cycled at an appropriate rate between two potential limits. The surfaces of the electrodes, obtained after injection of the biphasic charge as defined in a physiological solution (0.9% NaCl), thus simulating long-term electrical stimulation, were investigated using a high resolution Auger electron spectroscopy (AES) method.