Rice University scientists in Houston have cooked up a modular two-bacterium sensor that converts hard-to-spot chemicals into a readable electrical current. The platform, called e‑COSENS, divides the job between an engineered "sender" microbe and a natural "receiver" microbe, which the team says makes the setup surprisingly adaptable to messy real-world samples. In early lab runs, the group wired the microbes to compact electronics meant for use outside traditional labs and saw clear responses in everything from bayou water to grocery-store milk and artificial saliva.
How e‑COSENS splits sensing and power
In the e‑COSENS design, the sender bacterium only produces a quinone mediator when it detects a target analyte. Once that quinone shows up, the receiver bacterium grabs it and shuttles electrons to an electrode, creating an electrical current that functions as the readout. This plug-and-play split lets researchers swap in different sensing modules without forcing a single microbe to handle every task, according to results published in Nature Biotechnology.
Bench tests covered milk, saliva, fecal samples and bayou water
To show the idea was not just a clever circuit on paper, the Rice team ran four analyte-detection systems in four different environments. One setup used an E. coli sender to spot heavy-metal ions and inflammation markers in bayou water and artificial saliva. Two others used L. lactis senders that detected antimicrobial peptides in fecal-derived samples and an antibiotic spiked into store-bought milk. "The strength of e‑COSENS is the flexibility derived from sharing the work across multiple cells," said corresponding author Caroline Ajo‑Franklin, as reported by Rice University.
Quick electrical readouts, from minutes to hours
When the team hooked their microbe-filled reactors to current meters, all four systems generated a measurable electrical charge within a few hours, and some configurations responded in roughly 20 minutes. The authors also describe a centimeter-scale readout that can be paired with an off-the-shelf household digital multimeter. In the paper, published in Nature Biotechnology, that low-cost hardware pairing is pitched as a step toward field-ready diagnostics that do not require a full laboratory bench.
Patents, funding and steps toward commercialization
The Rice group has filed provisional patents on both the e‑COSENS design criteria and a microbial fuel cell device tailored to work with a standard multimeter. According to Rice University, the project received support from the Army Research Office and the Cancer Prevention and Research Institute of Texas. The filings are meant to protect the technology as the team pushes toward portable prototypes and wider testing outside the lab.
What comes next
The authors present e‑COSENS as a flexible platform for both environmental and health monitoring, but they also stress that the work is still at the proof-of-concept stage. The controlled-sample runs and focus on low-cost hardware are early steps. It will take broader field trials and careful biosafety review before city agencies or clinics could realistically lean on this type of microbial sensor, an inference supported by the published manuscript and supplemental material archived at PubMed Central.
