A central challenge in nanoscience is the organization of functional components into deliberately designed patterns, and the ability to modify these patterns at will. Because of its molecular recognition specificity and structural features, DNA presents a unique opportunity to address this problem. Our research group has been examining a new approach to build DNA nanostructures, in which synthetic molecules are used to control DNA self-assembly. This approach results in combining the diverse structural features of synthetic organic or inorganic molecules, as well as their multiple functionalities, with the programmable character of DNA. Specifically, we will describe (a) the modular, quantitative and simplified synthesis of 3D-DNA structures, such as DNA nanocages and nanotubes. These are created with deliberate variation of geometry, size, single- and double-stranded forms and persistence lengths. Their internal volume can be readily switched with added DNA strands. These architectures are important for encapsulation and delivery of biomolecules, as interconnects and as templates for materials growth; (b) the use of DNA to precisely position gold nanoparticles, as well as transition metals, into well-defined, discrete 2D- and 3D-structures. These materials are fundamentally important to nanoelectronic, nanooptics and catalysis; (c) the use of small molecules to effect profound changes in DNA nanostructures. Small molecules can correct ?errors? in DNA organization, and can also completely reprogram DNA self-assembly, thus expanding the DNA code into new unnatural forms; (d) the hierarchical assembly of dendritic DNA ?block copolymers? into well-defined one-dimensional structures. Thus, bringing the toolbox and concepts of supramolecular chemistry into DNA nanotechnology can enrich this field with new structures and new applications in biology and materials science.

References and Footnotes

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