Self-assembly of DNA origami nanoparticles into 2D tiling patterns

Self-assembly is a promising strategy for building functional nanoscale structures. Recent developments in molecular engineering, especially DNA nanotechnology, allow us to create complex nanoscale building blocks, opening up possibilities to create diverse patterns and geometries through self-assembly. However, as the assembly complexity increases, the number of unique sets of specific interactions quickly diverges, often hindering the exploration of the full breadth of accessible structures. In this talk, I will show how orthogonal local interactions lead to rich geometrical patterns, and that such patterns can be assembled in experiment using DNA origami nanoparticles. By enumerating all deterministic patterns accessible using up to four species of triangular building blocks that interact edge to edge, we find a zoo of 2D patterns, including fully addressable structures, linear tilings, and planar tilings. To characterize the assembly of these patterns in experiment, we design triangular subunits from DNA origami, which are each 50 nm in size, and encode specific interactions between their edges using sticky ends. We find that by tuning the interaction strength between edges, thousands of particles can crystallize into a single triangular sheet spanning microns in size. We also succeed in assembling noncanonical tiling patterns using multiple species of triangles, which enables us to control the relative location and orientation of triangles in a micron-scale object.