(413e) The Use of Phage-Selected Peptides On Microcantilevers for Rapid Detection of Salmonella

We report the use of a microcantilever sensor designed to measure the specific binding of Salmonella to immobilized phage selected peptide. An anti-Salmonella antibody is compared for specificity and selectivity against four peptides obtained from a phage display library. Particularly, the specificity of this sensor was investigated by distinguishing Salmonella from other bacteria (Listeria monocytogenes and Escherichia coli). We are also able to distinguish among eight Salmonella variants. A Langmuir isotherm model was applied to describe the molecular interactions on sensor surface and to assess the binding affinity constants of peptides. Both experimental and modeling results illustrate a peptide (MSal 020417) with better performance than commercially available antibody. In addition, various functionalization of different cantilevers on the same sensor chip allows simultaneous testing of multiple binding peptides and synchronous detection of multiple pathogens, which highly improves the efficiency of the detection. In summary, the microcantilever based technique provides a way to rapidly and accurately detect pathogens, as well as a high potential to be further developed as a screening method to identify pathogen specific binding candidates.