Fig. 2.

Schematic display of formation processes of DNA origami and DNA nanocages (DNA tetrahedron and DNA bipyramid). Colored lines represent different oligonucleotides. (A) A long-circulated plasmid DNA could be folded by many short oligonucleotides (staple strands) to form DNA origami nanocomposites with specific patterns, such as rectangles, stars, smiling faces, and triangles. Adapted with permission from [48]. (B) Four oligonucleotides could hybridize with each other to form 3-dimensional DNA tetrahedron-shaped nanocages. Adapted with permission from [52]. (C) Formulation of 3-dimensional DNA nanostructures with multivalent DNA bricks. Adapted with permission from [56].