|Institution:||University of Notre Dame|
|Keywords:||biosensor; pyoverdin; deferoxamine; self-assembly; xenosiderophore; dark field microscopy|
|Full text PDF:||http://etd.nd.edu/ETD-db/theses/available/etd-07112013-151604/|
Bacterial pathogens are constantly evolving resistance to the most common treatments, thus there is a critical public health need for more rapid methods, such as biosensors, to accurately detect and identify infections. Microorganisms including Pseudomonas aeruginosa secret microbial iron chelators (siderophores) to gather the vital nutrient iron. The research presented herein employed the exquisite selectivity of microbe- to- iron chelator interactions on gold detector surfaces to direct capture, identification, and characterization of bacteria. Dielectrophoresis used in conjunction with siderophore functionalized surfaces improved bacteria surface coverage by a factor of 30 for Pseudomonas aeruginosa strain PA01, and showed an 8 fold improvement compared to PA6. Detection of the capture bacteria was further quantified through surface plasmon resonance phase imaging, which demonstrated a signal response 5 times greater than the minimum measurable signal. Future work target additional optimization of the sensing platform to resolve bacteria signal below 20 minutes.