21.1 Nanowatt circuit interface to whole-cell bacterial sensors

Genetically engineered, re-programmable bacterial cells are fast emerging as a platform for small molecule detection in challenging environments [1]. A key barrier to widespread deployment of autonomous bacterial sensors is the detection of low-level bioluminescence, which is typically quantified with power-hungry (watt-level) detection hardware such as Photo Multiplier Tubes (PMT). Prior work has reported successful integrated mW-level detection of bioluminescence by using PN / PIN photodiodes with OTA-based [2] and active-pixel-sensor circuits [3,4]. Our goal was to develop an even lower power readout to enable harvesting as a viable source of energy for a future batteryless autonomous biological sensor node, with applications in distributed remote environmental sensing, or in vivo biochemical sensing.