A 8 × 12 array of integrated potentiostats for on-CMOS neurotransmitter imaging is presented. Each potentiostat channel measures bidirectional redox currents proportional to the concentration of a neurochemical. By combining the current-to-frequency and the single-slope analog-to-digital converter (ADC) architectures a total linear dynamic range of 95 dB is achieved. A 3.8 mm × 3.1 mm prototype fabricated in a 0.35 μm standard CMOS technology was integrated with flat and 3D on-die gold microelectrodes and an on-chip microfluidic network. It is experimentally validated in in-situ recording of neurotransmitter dopamine.