Sensing by Smell: Nanoparticle–Enzyme Sensors for Rapid and Sensitive Detection of Bacteria with Olfactory Output

We present here a highly efficient sensor for bacteria that provides an olfactory output, allowing detection without the use of instrumentation, and with a modality that does not require visual identification. The sensor platform uses nanoparticles to reversibly complex and inhibits lipase. These complexes are disrupted in the presence of bacteria, restoring enzyme activity and generating scent from odorless pro-fragrance substrate molecules. This system provides rapid (15 min) sensing and very high sensitivity (102 cfu/mL) detection of bacteria using the human sense of smell as an output.