An electrochemical sensor concept for the detection of bacterial virulence factors from Staphylococcus aureus and Pseudomonas aeruginosa

•Redox probes containing lipid vesicles for the detection of bacterial virulence factors and supernatants•Bacterial toxins open the vesicles and trigger the release of redox couples to be detected by screen printed electrodes.•Pathogenic S. aureus and P. aeruginosa are discriminated from non-pathogenic E. coli by redox current response•Detection limit of toxins by vesicles is one order of magnitude lower than cytotoxic dose of similar toxins to T lymphocytes

This work presents an electrochemical sensor concept for bacterial toxin detection using biomimetic lipid vesicles containing potassium ferricyanide. The toxin mediated release of redox couples from the vesicles was quantified by measuring the redox current on screen printed electrodes, and the detection limits to rhamnolipid, delta toxin and bacterial supernatants from clinical wound pathogens were examined. Overall detection limits of both redox and carboxyfluorescein containing vesicles were one order of magnitude lower than the cytotoxic dose of studied toxins to T lymphocytes.

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