The aim of this research is to develop new dielectrophoretic (DEP) chips comprising three-dimensional insulating structures and passivated electrodes for low-cost, high-throughput, and selective isolation and enrichment of different pathogens in water.
Intellectual Merits: We will combine advanced 3D silicon micromachining technologies, soft lithography, and DEP techniques to develop three-dimensional passivated-electrode insulator-based dielectrophoresis (3D-£kDEP) chips for pathogen enrichment. The 3D-£kDEP chip, which consists of several zones with arrays of three-dimensional microstructures on a PDMS-glass platform, alleviates the shortcomings of the current electrode-based DEP and insulator-based DEP mechanisms by utilizing 3D insulator structures for generating strong electric field gradients and using passivated electrodes to apply the required AC voltage for selective isolation/trapping of bioparticles including pathogens. The 3D-£kDEP chips can be used to characterize the DEP properties and selectively trap Methicillin-resistant Staphylococcus aureus (MRSA) and Escherichia coli (SMS-3-5) as model Gram positive and negative bacteria. 3D-£kDEP devices will be validated by benchmarking the results obtained against quantitative polymerase chain reaction (qPCR) which works by quantifying a target gene copy known to be specific to the pathogen of interest.
Broader Impacts: This research leads into the development of a new DEP method with high flexibility in design and operation while providing scalable throughput for separation and enrichment of particles in biological fluids. The research also promotes teaching and learning at the high school, undergraduate, and graduate levels. This includes: 1) REU opportunities for undergraduates, 2) recruiting of graduate students into a highly interdisciplinary research program, 3) lab tours and lecture presentation for high school students participating in VT Pre-College Initiative and College outreach activities, 4) incorporation of the project results in the courses taught by the PIs in different departments, and 5) joint seminars by the PIs. Additionally, the outcome of this research will be widely disseminated to the engineering and scientific communities in peer-reviewed journals and in presentation at multidisciplinary conferences.
