Rapid, Selective, and Ultra-Sensitive Field Effect Transistor-Based Detection of .

() was among the first organisms to have its complete genome published (Genome Sequence of 1997 Science). It is used as a model system in microbiology research. can cause life-threatening illnesses, particularly in children and the elderly. Possible contamination by the bacteria also results in product recalls, which, alongside the potential danger posed to individuals, can have significant financial consequences. We report the detection of live () in liquid samples using a biosensor based on a field-effect transistor (FET) biosensor with B/N co-coped reduced graphene oxide (rGO) gel (BN-rGO) as the transducer material. The FET was functionalized with antibodies to detect K12 O-antigens in phosphate-buffered saline (PBS). The biosensor detected the presence of planktonic bacterial cells within a mere 2 min. The biosensor exhibited a limit of detection (LOD) of 10 cells per sample, which can be extrapolated to a limit of detection at the level of a single cell per sample and a detection range of at least 10-10 CFU/mL. The selectivity of the biosensor for was demonstrated using () as a sample contaminant. We also present a comparison of our functionalized BN-rGO FET biosensor with established detection methods of k12 bacteria, as well as with state-of-the-art detection mechanisms.