Integrated Circuit Architecture for Real-Time Sensing with Embedded Microbial Whole-Cell Sensors

Abstract

Bacteria sense a diverse range of environmental analytes with high sensitivity and temporal resolution. Engineering and synthetic biology approaches enabled harnessing this capability through development of whole-cell biosensors that respond to specific molecules of interest. However, converting these responses into electrical signals in real time, across different environmental conditions, in miniaturized, field-deployable microelectronic devices, remains challenging. Here we present a bioelectronic platform that directly couples engineered bacteria to an integrated circuit (IC) chip through custom on-chip microelectrodes, enabling real-time, electronic readout of analyte sensing through bacterial flagellar motor dynamics. Using non-Faradaic electrochemical impedance measurements the device resolves both the direction and speed of motor rotation with a signal-to-noise ratio (SNR) of 15 dB. The IC is further integrated with a microfluidic system that enables controlled delivery and removal of analytes, nutrients and bacteria. When combined with whole-cell biosensors engineered to detect specific analytes, this work provides a miniature, portable platform for continuous monitoring in a range of liquid environments.