The objective of this research is the development of a low-cost, disposable electrically-readable DNA sensor for use in field-deployed epidemiology and disease screening. The approach is the development of a novel DNA hybridization sensor architecture using the organic thin film transistors as the active sensing element. Initial results indicate that DNA molecules may be directly immobilized by physical adsorption on the exposed channels of bottom-gated organic transistors and may be used to implement a DNA microarray in conjunction with integrated microfluidics. The immobilized DNA molecules have been found to dope organic semiconductors, causing a threshold voltage shift. Importantly, single- and double-strand DNA show substantial difference in the resultant VT shift, enabling the direct electrical detection of hybridization. By combining these sensors with integrated polymer microfluidics, the investigators will develop a low-cost, field-deployable DNA microarray technology. Broader Impacts: This proposal is technically important since it will contribute to the development of a disposable, electrically-read, field-deployable disease-screening tool suitable for DNA sequencing at low-cost, directly performed in the field. This will be invaluable in epidemiological studies for tracing disease in poverty-afflicted parts of the world. Broader impacts of this proposal include mentorship of undergraduates in research, outreach to high-school students to facilitate their retention in science and engineering, and outreach to underrepresented minority groups through recruiting activities at historically black colleges and universities, with the goal of attracting underrepresented minority students into engineering research.
