Switching binary states of nanoparticle superlattices and dimer clusters by DNA strands

Abstract

Nanoscale components can be self-assembled into static three-dimensional structures, arrays and clusters using biomolecular motifs. The structural plasticity of biomolecules and the reversibility of their interactions can also be used to make nanostructures that are dynamic, reconfigurable and responsive. DNA has emerged as an ideal biomolecular motif for making such nanostructures, partly because its versatile morphology permits in situ conformational changes using molecular stimuli. This has allowed DNA nanostructures to exhibit reconfigurable topologies and mechanical movement. Recently, researchers have begun to translate this approach to nanoparticle interfaces, where, for example, the distances between nanoparticles can be modulated, resulting in a distance-dependent plasmonic response. Here, we report the assembly of nanoparticles into three-dimensional superlattices and dimer clusters, using a reconfigurable DNA device that acts as an interparticle linkage. The interparticle distances in the superlattices and clusters can be modified, while preserving structural integrity, by adding molecular stimuli (simple DNA strands) after the self-assembly processes has been completed. Both systems were found to switch between two distinct rigid states, but a transition to a flexible device configuration within a superlattice showed a significant hysteresis.

The surface plasmon modes of self-assembled gold nanocrystals

“…DNA-based assembly 14 has already generated considerable insight into one-dimensional 15 and 2D structures [16][17][18][19] , including the trimer, 18 tetramer 17 and pentamer 16 . 3D mesoscale tetrahedral and octahedral 20 systems have also been assembled using DNA as well as 2D 21,22 and 3D 23,24 lattices. However, although there have been reports of DNA-assembled 3D particle structures, they have invariably collapsed upon deposition onto a substrate, and no direct images of the structures could be obtained nor have optical studies been possible.…”

Direct measurements of DNA-mediated colloidal interactions and their quantitative modeling

“…Moreover, the temperature-dependent stability of such DNA bridges allows the resulting attraction to be modulated (1, 2) from negligibly weak to effectively irreversible over a convenient range of temperatures. Several groups have recently used such interactions to drive the assembly of three-dimensional (3D), crystalline structures from nanoscopic (4)(5)(6)(7)(8) and microscopic (9,10) particles. Ultimately, we envision a highly versatile nanomaterial design protocol in which a user-designed matrix of specific interactions among multiple particle species leads to sequential or even hierarchical assembly of complex particle structures, controlled by a user-designed thermal program.…”

Driving diffusionless transformations in colloidal crystals using DNA handshaking

“…NA has emerged as a versatile and effective means of directing the self-assembly of microscopic [1][2][3] and nanoscopic [4][5][6][7][8][9] particles into a variety of crystalline structures. Such crystals are stabilized by DNA handshaking 10 the formation of transient DNA bridges between particles bearing complementary DNA sequences-that induces a force drawing the particles together 1,[11][12][13][14] .…”