Point of Care, Clinical and Forensic Assays via DNA-Bead Aggregation

The work presented here focuses on the development of point of care medical device for CD4+ T-cells enumeration, and a filter paper based DNA quantitation assay, both assays are based on the DNA-silica beads aggregation, the “pinwheel effect”
Chapter 1 introduces the concept of microfluidics, and the materials used to fabricate microfluidics devices, devices for blood analysis, the status quo of the Point of Care Testing (POCT), and a brief overview of nanoparticles synthesis and their properties. Chapter 2 explores the pinwheel assay and its application on CD4+ T cells enumeration in tube, chapter 3 details the integrated CD4+ T-cell counting chip with 3 domains: extraction, metering and DNA-bead aggregation. Chapter 4 and 5 discuss the filter paper based DNA quantitation system, this simple and cost-effective assay was developed to quickly quantitate DNA and guide forensic tests like Short Tandem Repeat (STR). Silica coated magnetic nanoparticles were synthesized to study the mechanism of pinwheel effect, and the results have shown that the sensitivity of the ‘pinwheel assay' depends on the particle size. Finally the chapter 6 outlines future directions.