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Surface-assisted, tile-based DNA self-assembly is a powerful method to construct large, two-dimensional (2D) nanoarrays. To further increase the structural complexity, one idea is to incorporate different types of tiles into one assembly system. However, different tiles have different adsorption strengths to the solid surface. The differential adsorptions make it difficult to control the effective molar ratio between different DNA tile concentrations on the solid surface, leading to assembly failure. Herein, we propose a solution to this problem by engineering the tiles with comparable molecular weights while maintaining their architectures. As a demonstration, we have applied this strategy to successfully assemble binary DNA 2D arrays out of very different tiles. We expect that this strategy would facilitate assembly of other complicated nanostructures as well.
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DNA conformational equilibrium enables continuous changing of curvatures
Assembly of complex structures from a small set of tiles is a common theme in biology. For example, many copies of identical proteins make up polyhedron-shaped, viral capsids and tubulin can make long microtubules. This inspired the development of tile-based DNA self-assembly for nanoconstruction, particularly for structures with high symmetries. In the final structure, each type of motif will adopt the same conformation, either rigid or with defined flexibility. For structures that have no symmetry, their assembly remains a challenge from a small set of tiles. To meet this challenge, algorithmic self-assembly has been explored driven by computational science, but it is not clear how to implement this approach to one-dimensional (1D) structures. Here, we have demonstrated that a constant shift of a conformational equilibrium could allow 1D structures to evolve. As shown by atomic force microscopy imaging, one type of DNA tile successfully assembled into DNA spirals and concentric circles, which became less and less curved from the structure's center outward. This work points to a new direction for tile-based DNA assembly.
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- Award ID(s):
- 2107393
- PAR ID:
- 10409783
- Date Published:
- Journal Name:
- Nanoscale
- Volume:
- 15
- Issue:
- 2
- ISSN:
- 2040-3364
- Page Range / eLocation ID:
- 470 to 475
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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Abstract Tile‐based DNA self‐assembly is a powerful approach for nano‐constructions. 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?more » « less
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.1039/D2NR05404C
