Microdevices and Nanomaterials for Sensing and Diagnostics of Non-Communicable Diseases and Metabolic Parameters

Abstract

With increasing life expectancy, leading causes of death continue to shift away from infectious diseases and toward noncommunicable diseases (NCDs). Regular screening and monitoring are the best methods of early detection and treatment. Microdevices and nanomaterials have the potential to reduce the logistical impact of screening on patients, making them more likely to receive regular monitoring, and putting them in a better position for early detection of NCDs. Electrocardiogram (ECG) information and blood cell mechanical properties are two promising sources of diagnosis for CVD and cancer, respectively. The following dissertation describes the development, characterization and testing of various microdevices and nanomaterials for monitoring of biological parameters relevant to the presence of NCDs. An in-depth characterization of various Graphene-oxide (GO) composite materials has been performed on graphene-based materials, and their suitability for health monitoring systems. Next, a Nylon-GO composite fabric was produced, and fashioned into ECG electrodes, which demonstrated superior signal quality compared to clinically used gel-type Ag/AgCl electrodes. Then, the composite electrodes were implemented into a wearable, wireless monitoring system to measure the vital signs and parameters related to CVD. In the second part of the dissertation, two studies were performed to measure cell mechanical properties in microfabricated environments. Human fibroblasts were plated on patterned Si mazes and imaged over time to measure cell to substrate geometry interaction. Separately, a microelectronic DEP device was designed and fabricated to test the mechanical properties of white blood cells where THP-1 and Jurkat cell lines were electrically deformed, and their elastic moduli calculated. These experiments were repeated with the addition of gold nanoparticles with optional presence of PEG and citrate, to measure the effect on the electrical response of the cells. Results from deformation experiments show the potential for devices to be expanded into high throughput microfluidic screening and diagnostic tools.

Date of Award	Dec 2018
Original language	American English