ABSTRACT
Some of the useful motif types found in DNA nanostructures are stem loop, Holliday junction, and sticky ends. Sticky end is an unhybridized single-stranded DNA that protrudes from the end of a double helix and is often used to combine two DNA nanostructures via hybridization. Inspired by the DX motif, several other motifs were engineered, such as triple-crossover (TX) motif, paranemic crossover tiles (PX), three-, five-, and six-point star motifs, and T-junctions, to provide more options to fabricate DNA nanostructures. Another breakthrough in the design of the DNA nanostructure was achieved when Rothemund developed the concept of DNA origami. With the development of rigid and unique 3D motifs as well the assembling strategies, a variety of 3D DNA nanostructures are fabricated and reported in the literature. In addition to being useful as a practical lithography process, ways to fabricate a large-scale DNA nanostructure and its deterministic positioning on the substrate need to be developed.
