Engineering a multi-functional DNA origami nanorod for the control of nanoscale processes

Abstract

Processes that occur at the nanoscale are the foundational building blocks of our world. As such, there is considerable interest in ways to study and manipulate matter at this scale, with applications in biomedicine and other fields. DNA origami has emerged over the past decade as a promising technology for nanofabrication, offering the capacity for precise and tunable nanoscale synthesis while maintaining the ease and scale of bottom-up self-assembly. The goal of this work is to develop novel ways in which DNA origami can be used to manipulate nanoscale processes. To this end, I developed a single DNA origami nanorod which is used in two distinct studies, highlighting the multifunctionality of this structure. I first investigated the effect of iron oxide nanoparticle clustering on MRI contrast generation by organizing particles in precise patterns on the nanorod. I found that small changes in the number of attached iron oxide nanoparticles lead to significant enhancement in T2 relaxivity, while inter-particle spacing has a minimal effect. In the second part of thesis, I developed the first DNA origami molecular motor, which converts chemical energy into mechanical activity and demonstrates autonomous directed motion over micron distances. By leveraging the unique addressability of DNA origami, I found that these motors predominately exhibit a rolling motion and that this behavior can be tuned via small alterations to the nanorod. Combined, this work demonstrates two novel applications for DNA origami nanostructures. We expect this work will serve as an initial platform for further studies and open up a range of new possibilities for the use of DNA origami as MRI contrast agents and molecular motors.