A spectroscopically interrogated flow-through type toxicity biosensor

A simple immobilised cell biosensor is described which uses the MUVS (Metabolic Ultraviolet Spectroscopy) response as an assay for toxic compounds in water. Bacterial cells are immobilised in an agarose membrane in a flow cell. A sample of water is passed over the flow cell. The UV absorbence of the membrane, compared to a similar membrane lacking bacterial cells, is measured at 200 nm. When the cells are stressed so that their energy metabolism is reduced, their UV spectra change, and specifically their OD200 drops within 15 seconds of exposure to the toxin. The sensor has potential for use in rapid tests, and possibly continuous monitoring, of environmental samples for toxic contamination.