Multiplexing of Microelectrode Arrays in Voltammetric Measurements

Multipotentiostats are the equipment commonly used for voltammetric measurements with multichannel electrode arrays, because the conditioning of the working electrodes does not allow fast multiplexing for measuring current responses. In this article, multiplexing and serial read-out of electrode arrays using a simple potentiostat and integrated circuits are shown. Several specially constructed switches, which were integrated in an application specific integrated circuit (ASIC) in complementary metal oxide semiconductor (CMOS) technology, allow electrode potentials to be applied as if by a potentiostat during the read-out time as well as continuously applying a bias voltage during stand-by. The application of multiplexing and serial read-out is demonstrated by redox recycling of p-aminophenol in an interdigitated microelectrode array made in silicon technology. Here, a bipotentiostat generates two different potentials that are addressed by the ASIC to the anodes and cathodes for redox recycling. The results show the same quality as those using a multipotentiostat.