DNA origami bends into metamaterial fold

Researchers led by Yonggang Ke of Emory University and Georgia Institute of Technology have developed nanoscopic DNA “tiles” that could help scientists create materials and devices capable of doing unusual things with light (J. Am. Chem. Soc. 2016, DOI: 10.1021/jacs.6b03966). Ke and his colleagues turned to DNA origami to bend the nucleic acids into hexagonal tiles about 100 nm across. The DNA forms the sides of a hexagon, leaving a gap in a tile’s interior. These tiles can then self-assemble into larger honeycomb structures, including sheets and tubes, depending on the precise geometry and flexibility of individual tiles and the DNA strands linking them together. The gaps within the tiled framework of a sheet or tube also provide ideal places for gold nanoparticles to nest, the team found. This allowed the researchers to position these nanostructures with extreme precision and thereby create a metamaterial, a synthetic material with unnatural properties. In this case, the metamaterial interacts with light in strange ways. For instance, shining light on gold-decorated DNA tiles magnetized the structures, demonstrating that DNA origami provides a precision tool for researchers developing novel metamaterials, which could even include cloaking materials, the team reports.