An 8×8 CMOS microelectrode array for electrochemical dopamine detection

This work presents the design and characterization of an integrated CMOS (complementary metal oxide semiconductor) electrochemical sensor array for dopamine (DA) detection. The chip is intended to provide as a platform for high-throughput measurement of neurotransmitter release during exocytosis. Interdigitated gold microelectrodes with a 5-μm gap are fabricated on CMOS chips by a post-CMOS lithographic process. A buffer with a class-AB output stage is used for on-chip cell stimulation. The sensing circuits are placed beneath the microelectrodes and each sensor has a size of 160 × 150 μm². Both reduction and oxidation currents are successfully detected under a dopamine concentration of 10 μM.