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A 8\,\times\,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\,\times\,3.1 mm prototype fabricated in a 0.35 \mu m 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. [ABSTRACT FROM PUBLISHER]

A hybrid CMOS-microfluidic microsystem for chemiluminescence and electrochemiluminescence-based biochemical sensing is presented. The microsystem integrates a two-layer soft polymer microfluidic network and a CMOS imager fabricated in a standard 0.35-\mum technology. The CMOS imager consists of a 64\,\times\,128-pixel array interdigitated with a 32\,\times\,64 electrolessly plated nickel–gold microelectrode array. A two-transistor reset path technique attenuates the subthreshold leakage current of the reset transistor which constitutes a significant portion of the dark current. An active reset technique, in-pixel flicker noise cancellation, and pixel binning contribute to noise reduction. The imager achieves a low dark current of 3.6 nA/cm^2 for photodiode reset voltages as high as 2.3 V, noise of 110 \muVrms with maximum time of photon integration of 90 s, and a dynamic range of 67.8 dB. The CMOS-microfluidic microsystem is validated in on-chip chemiluminescence and electrochemiluminescence detection of luminol. [ABSTRACT FROM PUBLISHER]