LEGO construction of nanoparticle assemblies

(Nanowerk News) Scientists developed a new method of selectively attaching DNA strands to specific regions of nanoparticles. The DNA strands then dictate how the nanoparticles assemble into more complex architectures. The team used this approach to demonstrate 24 different nanoarchitectures (Nature Materials, "Regioselective surface encoding of nanoparticles for programmable self-assembly").
Scientists have demonstrated a new way to modify the surfaces of nanomaterials. This allows them to program and create complex nano-sized assemblies. The method's versatility will help scientists study how particles of different sizes, shapes, and composition interact in these assemblies. This will enable researchers to design and create self-assembled nanoarchitectures with new capabilities. The method produced viewable 3D images of the resulting nanocube.
Electron tomographic reconstruction (right) of programmed assembly of a nanoarchitecture built by attaching spherical particles to the six flat faces of a gold nanocube
Electron tomographic reconstruction of programmed assembly of a nanoarchitecture built by attaching spherical particles to the six flat faces of a gold nanocube. (© Nature Materials)
Starting in the 1990s, scientists developed techniques that use DNA to program how nanomaterials self-assemble into larger structures. The challenge is programming how nanoparticles self-assemble and the direction of their self-assembly interactions.
Researchers achieve this control by selectively encoding specific locations on the surface of nanoparticles with DNA. This DNA controls how the nanoparticle components self-assemble into a specific complex structure that scientists have designed for a particular nanoarchitecture.
This new research demonstrates a new, two-step method to use colloidal nanoparticles with DNA strands to control the direction those particles tend to bond. This allows scientists to control how the molecules in nanoparticles interact so that they can in turn produce nanoparticles that self-assemble in specific ways to result in specific nanoparticle architectures.
The team used tomographic reconstructions in a transmission electron microscope (TEM) for 3D structural characterizations of nanoassemblies with particles of different sizes, shapes, and compositions. The TEM images can be used to view a 3D rotation of the resulting nanocube. The observed selective and directional binding modes lead to the formation of the resulting nanoparticle architectures.
These complex architectures are difficult to accomplish using other approaches. The research was conducted at the Center for Functional Nanomaterials a DOE scientific user facility.
Source: U.S. Department of Energy, Office of Science
Subscribe to a free copy of one of our daily
Nanowerk Newsletter Email Digests
with a compilation of all of the day's news.
 
These articles might interest you as well: