2023-11-06 13:43:16
Los quasicrystals They are ordered but non-repetitive crystal structures, with patterns similar to mosaic structures, that have long baffled the scientific community. The existence of quasicrystals has been an enigma for decades and their discovery was worthy of the Nobel Prize.
Now, a team of researchers from the Center for Cooperative Research in Biomaterials CIC biomaGUNE (Basque Country), the International Institute of Nanotechnology at Northwestern University and the University of Michigan (both in the USA) has revealed a novel methodology to design colloidal quasicrystals using DNA. This pioneering study in the field of nanotechnology is published in the journal Nature Materials.
Study shows that the programmable nature of DNA can be harnessed to deliberately design and assemble quasicrystals
“It is very difficult to prepare particles with this geometry in sizes of about 100 nm and with a size uniformity good enough to make it possible to generate these quasicrystalline structures,” explains one of the authors, Professor Ikerbasque from CIC biomaGUNE. Luis Liz Marzan.
“While several examples are now known, discovered in nature or by serendipitous (chance) routes, our research demystifies their formation and, more importantly, shows how we can harness the programmable nature of DNA to deliberately design and assemble quasicrystals,” points out the co-author Chad Mirkinfrom Northwestern University.
The research started from a proposal from the group of Bionanoplasmonics of the Basque center, a pioneer in the development of manufacturing methods and modification of the surface of nanoparticles to improve their application possibilities: “We had found precisely the way to synthesize nanoparticles with decahedral geometry – particles with ten sides – and with sufficient quality to address this study,” says Liz Marzán.
Importance of geometry
“The decahedral geometry It is essential in this case because of the pentagonal symmetry it implies –he adds–. “Pentagons are essential geometric elements in quasicrystals and this is what has allowed us to achieve such special materials.”
For its part, the group led by the teacher Sharon Glotzer from the University of Michigan had already predicted the first quasicrystal of layered nanoparticles in 2009: “In our original simulation of the quasicrystal, the arrangement of the decahedra left very small spaces between them. Here, those gaps would be filled by DNA.”
An innovative approach opens new avenues for design at the nanoscale, according to its creators
The study has focused on the assembly of decahedral nanoparticles using DNA as a guiding structure, in a colloidal medium: “That is, in a non-homogeneous medium in which the particles are suspended in a fluid,” explains Liz Marzán.
Through a combination of computer simulations y experimentsthe team has discovered something extraordinary: these decahedral nanoparticles can organize to form quasicrystalline structures with fascinating pentagonal and hexagonal motifs (penta and hexacoordinated), culminating in the creation of a dodecagonal quasicrystal.
A robust quasicrystalline structure
“Decahedral nanoparticles have a fivefold symmetry “a feature that challenges the conventional norms of periodic mosaics,” explains Professor Mirkin. “By taking advantage of the programmable capabilities of DNA, we have been able to direct the assembly of these nanoparticles into a robust quasicrystalline structure.”
The research team has functionalized gold nanoparticles decahedral with short double-stranded DNA and has applied a precisely controlled cooling process to facilitate assembly. “We have attached DNA chains to the nanoparticles, to direct their arrangement, even reversibly because it is sensitive to temperature,” says Liz Marzán.
Decahedral gold nanoparticles have been functionalized with short DNA and a precisely controlled cooling process has been applied to facilitate assembly
The resulting quasicrystalline superlattices have shown a mid-range quasiperiodic order, with rigorous structural analyzes confirming the presence of a twelve-fold symmetry and a triangular-square mosaic pattern, distinctive features of a cuasicristal dodecagonal.
“By engineering colloidal quasicrystals, we have achieved an important milestone in the field of nanoscience. Our work not only sheds light on the design and creating intricate nanoscale structuresbut also opens a world of possibilities for advanced materials and innovative nanotechnological applications,” declared the CIC biomaGUNE professor.
“The implications of this advance are far-reaching, as it offers a possible model for the controlled synthesis of other complex structures that were previously considered unattainable,” the researchers note. As the scientific community explores the limitless prospects of programmable matter, this research paves the way for breakthroughs and transformative applications in various scientific fields.
Fuente: CIC biomaGUNE
Rights: Creative Commons.
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