192-channel CMOS neurochemical microarray

A 16×12-channel neurochemical microarray is presented. Each channel acquires bidirectional currents down to pico-amperes proportional to the concentration of a neurochemical. By combining the current-to-frequency and the single-slope analog-to-digital converter (ADC) 110dB of dynamic range is achieved. The ADC in each channel generates a 16-bit output in less than a millisecond. The microarray with flat and 3D gold electrodes and an on-chip microfluidic network is experimentally validated in in-situ recording of neurotransmitter dopamine.