ASSEMBLY AND ACTUATION OF MULTI-BLOCK TETHERED DNA ORIGAMI

DNA origami is an emerging technique that creates complex nanostructures and devices through molecular self-assembly by folding a large scaffold strand into a short staple strands. Recent efforts have sought to integrate these devices into higher order assemblies, but these have largely focused on static assemblies. Here we take a unique approach of making material building blocks with multiple sub-units tethered together to self assemble soft networks with tunable properties. We designed dynamic nanodevices that can undergo large configurations.Our design achieves this by having two double-stranded DNA (dsDNA) bundle structures, each approximately 40 nm long and 5-10 nm in cross-section dimensions, which are tethered together by a strand that can convert between single-stranded DNA (ssDNA), which coils up on itself, and relatively stiff dsDNA. Gel electrophoresis images confirmed that the structures were folded well, and transmission electron microscopy (TEM) imaging revealed that the ssDNA tether results in the blocks being close together, separated by distances of ~10 nm, while the dsDNA tether results in large separation of ~89 nm. Dynamic actuation can be achieved by converting the tether from ssDNA to dsDNA or vice-versa through DNA strand binding or strand displacement. Next steps will focus on reversible actuation and building higher order network assemblies. This work provides the guiding principles of DNA origami for larger reconfiguration which is useful for robotic or sensing materials.