Poster abstracts

Poster number 2 submitted by Ariel Robbins

Cooperative control of a DNA origami force probe

Ariel Robbins (Biophysics - Ohio State University), Peter Beshay (Mechanical and Aerospace Engineering - Ohio State University), Hazen Hildebolt (Physics - Ohio State University), Michael Neuhoff (Physics - Ohio State University), Ralf Bundschuh (Physics - Ohio State University), Carlos Castro (Mechanical and Aerospace Engineering - Ohio State University)

Abstract:
DNA origami (DO) nanotechnology has tremendous promise in developing nanodevices for complex functions including mechanically aided drug delivery, molecular sensing, force sensing, and probing single molecule dynamics. Complex and dynamic 3-dimensional DO nanodevices can perform prescribed functions through controlled actuation making their use precise and reproducible. In this study, we focused on the NanoDyn, a previously reported force sensor. This device consists of two origami bundles linked by six parallel 116 base single strand connections that can exist in either an open or closed configuration using a single DNA oligonucleotide zipper strand. By adjusting the number, length, and sequence of the zipper strand, the NanoDyn can be programed to open at a prescribed force. We employ single molecule force spectroscopy to characterize the mechanical behavior of this device. We show that the opening force can be easily adjusted between 6-12pN by changing the zipper strand length, with the potential to achieve higher force openings by incorporating multiple zipper strands in parallel. We also show that the zippers can be incorporated post-folding, allowing for rapid tuning of the device, and eschewing the need to fold and purify a separate structure for different force applications, which can take hours to days. Furthermore, we demonstrate that multi-zipper interactions significantly increase the efficacy of returning devices to their starting, closed, state. This work demonstrates a modular and versatile force probe that can ultimately be used in biological systems where traditional force spectroscopy techniques are more challenging to implement.

Keywords: DNA Origami, Force Spectroscopy, Nanotechnology