Microbial bioelectronic sensors for environmental monitoring

In a world confronting pollution across diverse environments, fast, sensitive and cost-efficient methods are required to monitor complex chemicals. In particular, microbial bioelectronic sensors can report on the presence of chemicals through electrical signals enabled by biological processes. For example, microbial bioelectronic sensors have been developed for the rapid detection of riverine toxins within minutes of contact, for selective sensing of redox-active pharmaceuticals, and for monitoring of pesticide degradation. However, transferring these laboratory-tested technologies into field-deployable products poses several challenges: sensor sensitivity, specificity, longevity and robustness need to be improved. In this Review, we discuss the design of field-deployable microbial bioelectronic sensors, including chassis selection, approaches for rewiring electron transfer, strategies to establish the cell–electrode interface and fabrication methods. Importantly, we outline key challenges and possible solutions for the application of such sensors in the real world.