Adsorptive stripping analysis of trace nickel at iridium-based ultramicroelectrode arrays

Lithographically fabricated iridium-based mercury microelectrode arrays are shown to be very suitable for adsorptive stripping measurements of trace n ickel in the presence of the dimethylgloxime complexing agent. Variables af fecting the response have been assessed and optimized. The sensor optimizat ion has resulted in a favorable and highly stable response, with good linea rity and precision (RSD = 1.7 %), and a low detection limit (0.5 mu g/L wit h 30s adsorption). Such adsorptive shipping performance makes the iridium-b ased microelectrode array very attractive for on-site measurements of trace metals that cannot be plated electrolytically.