Tile forming sequence

Fig. 14 Interacting triangular tiles, (a) Sequences are designed so to assemble in two different triangular tiles with complementary sticky ends, (b) Six connected triangles form hexagonal units, which (c) create a two-dimensional crystal, (d) AFM image (edge size is 133 nm) of two overlapped hexagonal tilings. Adapted with permission from [69]...

When a molecule is chiral, then it will have two isomeric forms called enantiomers, each of which is the nonsuperimposable mirror image of the other. Enantiomers are distinct stereoisomers because they are compounds that have die same molecular formula and sequence of bonded elements but which differ in tile spatial arrangement of groups in the molecule. If a molecule is chiral, and thus has two enantiomers, it usually (but not always) contains at least one chiral center. In organic compounds a chiral center usually corresponds to an asymmetric tetrahedral carbon atom. 

Fig. 16 (a) Three-point-star DNA motif with sticky ends, formed by seven sequences, (b) Two families of such motifs can bind and yield a two-dimensional array, (c) AFM imaging of the structure in (b) the inset shows the associated Fourier pattern. Adapted with permission from [72]. (d) DNA 4x4 tile structure (nine sequences) two different tiles can produce a square lattice (e). (f) AFM surface plot of the structure in (e), edge size is 150 nm. Adapted with permission from [73]... 

Fig. 23 Schematic illustration of the formation of a nanotube from a single sequence composed of four self-complementary segments (shown in different colors in (a)) the strand forms DX tiles (b) which then assemble into folded sheets (c, d). Adapted from [105]...

Self-assembly of arrays that could tile 3D space relied on pieces that were completely coated with lubricant (Fig. 4.20) [ref. 15]. The sequence of steps for self-assembly of these arrays is similar to that seen in molecular-scale crystallization a few blocks initially bond and form a nucleus these initial small... 

Figure 5.47 Design and modeling of DNA nanotubes. (I) Representation of two crossed-over double-strand DNAs forming the core of a tile, shown as a rectangle. (II) RE tile, which can bind only to itself (the colors of the terminal single stains show complementary sequences). (Ill) SE tile, which can bind to itself. Two cores form (IV) a diagonal lattice and (V) a perpendicular lattice. ...

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