(98c) Weak Interactions on an Oscillating Micro-Electrode Array

Johnson, K. C., University of Minnesota

The electrodissolution of nickel electrodes with resistance in sulfuric acid provides a model for studying oscillations in chemical and biological systems. A nickel microelectrode array was used to look for interactions between current oscillations. These interactions had not previously been observed in nickel systems. Interactions were observed on electrode pairs and were further studied for dependence on acid concentration, separation distance, and applied potential. The interaction effects, which were not strong enough to cause synchronization, were asymmetric; one electrode exhibited periodic variations in amplitude and waveform that the other electrode did not. Acid concentration and electrode distance were not shown to have an effect on either phase difference or waveform effects. The applied potential did influence the interactions, with smaller phase differences and more-defined waveform disturbances occurring at higher potentials. Future experiments with larger numbers of electrodes will look for more complex interactions and pattern formation. It is hoped this research will provide insight into biological systems such as epilepsy and circadian rhythms.