Abstract

Antibiotic resistant infections are a growing health care concern, with many cases reported annually. Infections can cause irreversible bodily damage or death if they are not diagnosed in a timely matter. To rapidly diagnose antibiotic resistance in infections, it is important to be able to capture and isolate the DNA coding for the resistance genes. This is challenging because bacteria are present in blood in minute concentrations. To enrich the DNA to detectable levels, I modified magnetic microbeads with ssDNA sequences complementary to the target DNA to capture the DNA via hybridization. I compared DNA capture efficiency in three different methods: Co-flow, packed bead bed, and pre-hybridization. The pre-hybridized method worked better than the other two. Since pre-hybridization involved mixing, I chose to study mixing in a microfluidic device. The mixing chamber was a well carved out of PMMA placed between two electromagnets. To test the mixing well, beads and capture DNA were placed in it, and the electromagnets were subjected to different frequencies, including symmetric or asymmetric magnetic fields. For each condition the capture efficiency was determined by measuring the relative fluorescence units (RFU). A 100 Hz asymmetric magnetic field had the best capture efficiency out of all conditions. These results demonstrate a path for enriching low concentrations of DNA to detectable levels, and future work should be done to develop electromagnetic mixing in microfluidic devices.

Degree

MS

College and Department

Physical and Mathematical Sciences; Chemistry and Biochemistry

Rights

http://lib.byu.edu/about/copyright/

Date Submitted

2019-07-01

Document Type

Thesis

Handle

http://hdl.lib.byu.edu/1877/etd11379

Keywords

microfluidics, magnetic microbeads, antibiotic resistance, sepsis

Language

English

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