New Sensing Modalities for Bacterial and Environmental Phenomena

dc.contributor.advisorRubloff, Gary Wen_US
dc.contributor.authorBetz, Jordanen_US
dc.contributor.publisherDigital Repository at the University of Marylanden_US
dc.contributor.publisherUniversity of Maryland (College Park, Md.)en_US
dc.description.abstractIntercellular communication is a ubiquitous phenomenon across all domains of life, ranging from archaea to bacteria to eukarya. In bacteria, this is often achieved using small molecules that allow bacteria to sense and respond to environmental cues about the presence, identity, and number of neighboring bacteria. This confers survival and competitive advantages to bacteria by providing a coordinated, population-scale response to a given stimulus in the environment. This dissertation describes the development of a microfluidic system for immobilizing and culturing of cells that also enables control over the genetic composition of the bacteria and their subsequent response to environmental stimuli via a new nonviral nucleic acid delivery mechanism. This nonviral nucleic acid delivery occurs outside the parameter space of traditional nonviral nucleic acid delivery methods such as electroporation and chemical transformation. The bacteria are immobilized in an optically clear alginate hydrogel which simulates the physical and chemical environment normally experienced by bacteria in a biofilm. Complementing the microfluidic cell culture work, surface enhanced Raman spectroscopy (SERS), a label-free vibrational spectroscopic technique that lends itself well to use in aqueous systems, was used to detect bacterial signaling molecules. SERS was performed with three different examples of bacterial communication molecules: the universal quorum sensing molecule autoinducer-2 (AI-2), the species-specific Pseudomonas Quinolone Signal (PQS), and the stationary phase indicator molecule indole. SERS substrates were formed by galvanic displacement, a substrate fabrication method that can be adapted to many SERS applications. Taken together, these new sensing modalities represent a step toward developing systems that allow researchers to investigate, understand, and ultimately control a cell's response to its environment.en_US
dc.subject.pqcontrolledBiomedical engineeringen_US
dc.subject.pquncontrolledquorum sensingen_US
dc.subject.pquncontrolledsurface enhanced Raman spectroscopyen_US
dc.titleNew Sensing Modalities for Bacterial and Environmental Phenomenaen_US


Original bundle
Now showing 1 - 1 of 1
Thumbnail Image
8.98 MB
Adobe Portable Document Format