Assembly of Two‐Dimensional DNA Arrays Could Influence the Formation of Their Component Tiles

Abstract

Tile-based DNA self-assembly is a powerful approach for nanoconstructions. In this approach, individual DNA single strands first assemble into well-defined structural tiles, which, then, further associate with each other into final nanostructures. It is a general assumption that the lower-level structures (tiles) determine the higher-level, final structures. In this study, we present concrete experimental data to show that higher-level structures could, at least in the current example, also impact on the formation of lower-level structures. This study prompts questions such as: how general is this phenomenon in programmed DNA self-assembly and can we turn it into a useful tool for fine tuning DNA self-assembly?[a] V.

Design of Orthogonal DNA Sticky-End Cohesion Based on Configuration-Specific Molecular Recognition

“…The designated bonding of sticky-end partners would lead to an inter-tile double crossover (DX) bridge with crossover-to-crossover (X–X) distance of two turns (21 bp) (Figure c). Under our surface-assisted assembly condition of optimized ionic strength (see Methods and Notes for more details), individual tiles in solution were encouraged to be incorporated into large lattices through desired DNA–mica interaction. , This stringent assembly condition presumably served to screen out loosely assembled lattices on the surface. Not surprisingly, such a design led to tessellated 2D lattices with a regular square tiling pattern as presented in atomic force microscopy (AFM) images (Figures d and S1).…”

DNA Hyperstructure

“…Pincus et al conducted a study on this topic, finding that using spermine (a tetravalent cation) leads to structures of approximately 100 nm or even micrometers in size . In the laboratory, the condensation process is achieved through DNA oligomerization; − the use of salts with mono-, di-, and tetravalent cations in varying concentrations has been studied; , cationic surfactants and ethanol are also required to precipitate the DNA and create the conditions necessary for its self-assembly . In 1991, DNA was first observed under a light microscope (patent application filed in 1991 with the Mexican Institute of Industrial Property, granted in 1996) − with the goal of finding an alternative method to replace electrophoresis.…”