VOLTAMMETRIC MULTICHANNEL MEASUREMENTS USING SILICON FABRICATED MICROELECTRODE ARRAYS

A modular voltammetric multichannel detection system has been develope d for use in flow analysis. Two different types of multichannel potent iostats, an adjustable and a ground-fixed potentiostat, are realized. Both types work with up to sixteen independent working electrodes at o ne chip electrode array and are controlled through a personal computer and a microcontroller. Simultaneous difference pulse and cyclic volta mmetric procedures are realized. Platinum thin-film array electrodes h ave been arranged on silicon wafers as pairs of interdigitated microba nd electrodes (interdigitated array electrodes; IDA) with an interelec trode gap in the submicrometer range. Furthermore the multichannel ele ctrodes in a how system were used to characterize the highly sensitive flow profiles and flow rate measurements using redox mediators. A bri ef description of applying the multichannel device for 'window' stripp ing of heavy metals is given.