| In the last few decades, the onset rate of cancer and infectious disease are continuously growing. Therefore, better molecular diagnostics are much desired for more efficient healthcare in modern medicine practice. Molecular diagnostics are based on the measurement of genetic and proteomic parameters in clinical samples. They provide the healthcare personnel with crucial information on patients' health conditions that are essential for making clinical decisions. They also offer important surveillance data for implementing public health interventions and strategies. Current molecular diagnostics are usually limited to centralized facilities with long turnaround time that significantly hinders the timely clinical decisions and outcomes. Furthermore, many molecular diagnostic assays are complicated by low sensitivity and low quantification accuracy which greatly affect the reliability of the assays.;My thesis seeks to address these issues in current molecular diagnostics from two major aspects including the development of novel instrument platforms and molecular assays using advanced micro- and nano- technologies. The instrument platform I developed heavily relies on droplet microfluidics, and my ultimate goal is to construct a droplet microfluidics based lab-on-a-chip system for point-of-care molecular diagnostics with sample-to-answer capability. My novel molecular diagnostic assays utilize functional nanomaterials, such as quantum dots, magnetic nanoparticles, and nanomembrane, to improve the detection sensitivity and quantification accuracy for analyzing biomarkers such as DNA methylation and gene copy number variation.;The two aforementioned two aspects are addressed in Chapter 2 and Chapter 3, respectively.;In Chapter 2, I will first start by introducing a droplet PCR platform capable of high throughput methylation specific KR. Then I will demonstrate two droplet based sample-to-answer micro total analysis system. In the end of chapter, I will present some latest advancement in liquid handling in droplet microfluidics, including a micro magnetic gyromixer designed to speed up mixing in droplets, and surface energy traps for full range droplet operations.;In Chapter 3, I will focus on functional nanomaterials enabled molecular diagnostic assays. I will put the emphasis on the new phenomenon I discovered named quantum dot electrophoretic transformation as well as its applications in a number of molecular nanoassays. Meanwhile, I will also briefly discuss a nanoparticles enabled streamlined process for DNA methylation detection, and a new silica nanomembrane used to isolate DNA with better quality. |
