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Good overview of the state of the art from Mirkins gorup. 

A nanoparticle-based analogue to the Periodic Table of the elements, where rather than arranging entries by electronic configuration, they are arranged by nanoscale architectural feature (e.g., composition, size, shape, and surface functionality). Using this table as a guide, the design considerations associated with using nucleic acids to assemble these nanoparticle-based programmable atom equivalents (PAEs) into superlattices is discussed.

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http://arxiv.org/pdf/1301.1098v1.pdf

"DNA-Programmed Mesoscopic Architecture"

We study the problem of self-assembly of nanoparticles (NPs) into nite mesoscopic structures with a programmed local morphology and  complex overall shape. Our proposal is to use NPs directionally-functionalized with DNA (dfNP), as building blocks. The combination of directionality and selectivity of interactions allows one to avoid any unwanted metastable con gurations that would commonly lead to slow self-assembly kinetics even in much simpler systems. With numerical
simulations, we show that a variety of target mesoscopic objects, can be designed and self-assembled in near perfect yield. They include cubes, pyramids, boxes and even an Empire State Building model. We quantitatively describe the observed kinetics with a simple model, and put forward a compact set of design principles for dfNP-based mesostructures

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http://www.nature.com/nnano/journal/v7/n12/full/nnano.2012.211.html

"A mechanical metamaterial made from a DNA hydrogel"

Metamaterials are artificial substances that are structurally engineered to have properties not typically found in nature. To date, almost all metamaterials have been made from inorganic materials such as silicon and copper1, 2, which have unusual electromagnetic or acoustic properties1, 2, 3, 4, 5 that allow them to be used, for example, as invisible cloaks6, 7, 8, 9, superlenses10, 11, 12 or super absorbers for sound13. Here, we show that metamaterials with unusual mechanical properties can be prepared using DNA as a building block. We used a polymerase enzyme to elongate DNA chains and weave them non-covalently into a hydrogel. The resulting material, which we term a meta-hydrogel, has liquid-like properties when taken out of water and solid-like properties when in water. Moreover, upon the addition of water, and after complete deformation, the hydrogel can be made to return to its original shape. The meta-hydrogel has a hierarchical internal structure and, as an example of its potential applications, we use it to create an electric circuit that uses water as a switch.

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