PhD Thesis Proposal: Amogha Tadimety

Wednesday, April 17, 2019, 3:30–5:30pm

Rm. 105, Cummings Hall

"Nanoplasmonic Sensor Development for Circulating Tumor DNA Capture and Detection"

Abstract

Liquid biopsies, or the detection of biomarkers from a peripheral fluid sample rather than a tissue sample, offer promise for cancer screening, diagnosis, and monitoring. One biomarker of interest, circulating tumor DNA (ctDNA), can provide insight into tumor mutational profiles and epigenetics with a very short two-hour half- life. ctDNA poses a challenge for detection, however, due to its small size and low concentration, as well as the presence of point mutations that are difficult to differentiate from wild type sequences. Microfluidics combined with nanotechnology could combat these challenges through engineering high specificity and sensitivity to ctDNA.

This thesis proposes to use gold nanoparticles for plasmonic detection of sequence-specific ctDNA binding. The basic principle relies on the highly confined electric fields at the surface of gold nanoparticles, that have an ability to detect slight changes in dielectric environment. We can harness this property by functionalizing the nanoparticles to be selective to biomarkers of interest, and then can read out spectral shifts to transduce binding. This thesis will explore the development of plasmonic nanosensors for capture of ctDNA. Shape effects of particles will be studied through the use of gold nanorods and experimental and theoretical investigation of properties of gold-coated silica of multiple geometries. Particle arrangement is explored through studies of nanoparticles in solution and arrayed or randomly dispersed on chip. Finally, this platform will be applied to both ctDNA sensing applied to pancreatic ductal adenocarcinoma, and detection of the 16s RNA sequence relevant to bacterial detection. Together, this thesis will provide a framework for development of rapid, sample-to-answer nanoplasmonic sensors.

Thesis Committee

For more information, contact Daryl Laware at daryl.a.laware@dartmouth.edu.