CHIP-ARRAY ELECTRODES FOR SIMULTANEOUS STRIPPING ANALYSIS OF TRACE-METALS

An effective anodic-stripping method for the simultaneous detection of trace metals is described. For this purpose a sensor array consisting of three thin-film noble-metal microelectrode arrays made in silicon technology is designed. The use of a home-made multipotentiostat allow s parallel control of different potential-time regimes for each electr ode array. The trace metals are preconcentrated on the amalgamized ele ctrodes by applying the optimal potential for the respective metal. Af ter the deposition period, for every electrode a small potential windo w, specifically selected for the deposited metal, is scanned using dif ferential pulse voltammetry (dpv). Thus only one metal is detected on each electrode. This stripping regime ensures a short measuring time a nd simplifies the evaluation of the results. Furthermore, errors resul ting from intermetallic interactions in the amalgam layer are reduced.