A| Different Seeman tiles with diverse strand polarities34. B| Principles of
ssDNA brick assembly: each brick is a DNA single strand with four domains. When
each domain is 8 nucleotides long, its hybridization with an adjacent brick
produces a dihedral angle of 90 °. Each brick could be thought as a LEGO
binding to four other complementary LEGOs to form a cube61. C| The design
workflow starts with removing 3D pixels (voxels) from a 3D canvas followed by
generation of the corresponding strand diagram and sequences64. D| Transmission
electron microscopy (TEM) characterization of designed arbitrary shapes and
geometries (scale bars 100 nm)64. Panels A-C were adapted from REFs. 61, 64, 64, respectively, with permissions from AAAS and Springer
Nature. DX, double-crossover; JX, juxtaposed crossover; PX, paranemic crossover;
TX, triple-crossover,