Travis A. Meyer

Ph.D. Proposal Presentation

Date: Friday, January 20th

Time: 1:00 PM

Location: HSRB E-182, Emory University

Committee Members:

Yonggang Ke, Ph.D. (Advisor)

Gang Bao, Ph.D. (Advisor)

Hui Mao, Ph.D.

M.G. Finn, Ph.D.

Gabe Kwong, Ph.D.

Younan Xia, Ph.D.

Precise control over spatial organization and MRI contrast generation of superparamagnetic iron oxide nanoparticles using DNA origami

Superparamagnetic iron oxide nanoparticles (SPIOs) have received considerable interest as magnetic resonance imaging (MRI) contrast agents. One technique for improving the efficiency of SPIO contrast agents is to induce the self-assembly of individual nanoparticles into larger clusters. This change in contrast has also been utilized as a sensing mechanism for diagnostic assays, in which a target induces aggregation of stimuli-responsive SPIOs. However, the techniques used to induce SPIO clustering are relatively crude, limited to spherical geometries and resulting in polydisperse superstructures. In contrast, DNA origami has emerged as a promising technique for the precise organization of matter into arbitrarily prescribed shapes at the nanoscale. The goal of this work is to utilize DNA origami nanostructures to scaffold the arrangement of SPIOs into complex and well-defined superstructures. We hypothesize that these nanodevices will facilitate detailed mechanistic studies into the effect of three-dimensional SPIO organization on MRI contrast generation. In addition, triggered hierarchical assembly of DNA origami tiles bearing SPIOs will be used to construct monodisperse magnetic resonance switches, facilitating the reliable detection of a wide variety of clinically relevant targets.