A self-assembled DNA bipyramid

Nanometer-scale DNA polyhedra, consisting of 3- or 4-arm branch junctions connected by rigid double-helical edges, can be created by self-assembly protocols that exploit the specificity of base-pairing interactions. The DNA tetrahedron was the first such structure to be made rapidly and in high yield from multiple strands in a single assembly step. Facile and efficient synthesis is a necessary enabling step toward the application of these controllable three-dimensional scaffolds as building blocks for nanofabrication or as functional molecular cages. Herein we demonstrate the single-step assembly of a DNA trigonal bipyramid, demonstrating that more complex, less symmetric polyhedra can also be created by one-step assembly.