Navigation Links
Emulating -- and surpassing -- nature
Date:10/13/2011

Nature is a master builder. Using a bottom-up approach, nature takes tiny atoms and, through chemical bonding, makes crystalline materials, like diamonds, silicon and even table salt. In all of them, the properties of the crystals depend upon the type and arrangement of atoms within the crystalline lattice.

Now, a team of Northwestern University scientists has learned how to top nature by building crystalline materials from nanoparticles and DNA, the same material that defines the genetic code for all living organisms.

Using nanoparticles as "atoms" and DNA as "bonds," the scientists have learned how to create crystals with the particles arranged in the same types of atomic lattice configurations as some found in nature, but they also have built completely new structures that have no naturally occurring mineral counterpart.

The basic design rules the Northwestern scientists have established for this approach to nanoparticle assembly promise the possibility of creating a variety of new materials that could be useful in catalysis, electronics, optics, biomedicine and energy generation, storage and conversion technologies.

The new method and design rules for making crystalline materials from nanostructures and DNA will be published Oct. 14 by the journal Science.

"We are building a new periodic table of sorts," said Professor Chad A. Mirkin, who led the research. "Using these new design rules and nanoparticles as 'artificial atoms,' we have developed modes of controlled crystallization that are, in many respects, more powerful than the way nature and chemists make crystalline materials from atoms. By controlling the size, shape, type and location of nanoparticles within a given lattice, we can make completely new materials and arrangements of particles, not just what nature dictates."

Mirkin is the George B. Rathmann Professor of Chemistry in the Weinberg College of Arts and Sciences and professor of medicine, chemical and biological engineering, biomedical engineering and materials science and engineering and director of Northwestern's International Institute for Nanotechnology (IIN).

"Once we have a certain type of lattice," Mirkin said, "the particles can be moved closer together or farther apart by changing the length of the interconnecting DNA, thereby providing near-infinite tunability."

"This work resulted from an interdisciplinary collaboration that coupled synthetic chemistry with theoretical model building," said coauthor George C. Schatz, a world-renowned theoretician and the Charles E. and Emma H. Morrison Professor of Chemistry at Northwestern. "It was the back and forth between synthesis and theory that was crucial to the development of the design rules. Collaboration is a special aspect of research at Northwestern, and it worked very effectively for this project."

In the study, the researchers start with two solutions of nanoparticles coated with single-stranded DNA. They then add DNA strands that bind to these DNA-functionalized particles, which then present a large number of DNA "sticky ends" at a controlled distance from the particle surface; these sticky ends then bind to the sticky ends of adjacent particles, forming a macroscopic arrangement of nanoparticles.

Different crystal structures are achieved by using different combinations of nanoparticles (with varying sizes) and DNA linker strands (with controllable lengths). After a process of mixing and heating, the assembled particles transition from an initially disordered state to one where every particle is precisely located according to a crystal lattice structure. The process is analogous to how ordered atomic crystals are formed.

The researchers report six design rules that can be used to predict the relative stability of different structures for a given set of nanoparticle sizes and DNA lengths. In the paper, they use these rules to prepare 41 different crystal structures with nine distinct crystal symmetries. However, the design rules outline a strategy to independently adjust each of the relevant crystallographic parameters, including particle size (varied from 5 to 60 nanometers), crystal symmetry and lattice parameters (which can range from 20 to 150 nanometers). This means that these 41 crystals are just a small example of the near infinite number of lattices that could be created using different nanoparticles and DNA strands.

Mirkin and his team used gold nanoparticles in their work but note that their method also can be applied to nanoparticles of other chemical compositions. Both the type of nanoparticle assembled and the symmetry of the assembled structure contribute to the properties of a lattice, making this method an ideal means to create materials with predictable and controllable physical properties.

Mirkin believes that, one day soon, software will be created that allows scientists to pick the particle and DNA pairs required to make almost any structure on demand.


'/>"/>
Contact: Megan Fellman
fellman@northwestern.edu
847-491-3115
Northwestern University
Source:Eurekalert

Related biology news :

1. Borrowing from brightly-colored birds: Physicists develop lasers inspired by nature
2. Gene signature predicts oral cancer recurrence
3. Pragues 88 nature reserves threatened by invasive plant species
4. Child abuse in birds: Study documents cycle of violence in nature
5. Mother Natures oral antibiotics research gets $2.25 million help from NIH
6. Nature shows the way
7. MU researchers unveil new method for detecting lung cancer in Nature article
8. Mapping a model: International research on plant species appears in journal Nature
9. Nature reaches for the high-hanging fruit
10. Epigenetic memory key to nature versus nurture
11. New book on the meaning of nature connects vacations, corn, baseball
Post Your Comments:
*Name:
*Comment:
*Email:
(Date:11/15/2016)... Research and Markets has announced the addition of the ... offering. ... The global bioinformatics market is ... Billion in 2016, growing at a CAGR of 21.1% during the ... driven by the growing demand for nucleic acid and protein sequencing, ...
(Date:6/22/2016)... , June 22, 2016  The American College of ... Trade Show Executive Magazine as one of the fastest-growing ... May 25-27 at the Bellagio in Las Vegas ... the highest percentage of growth in each of the following ... exhibiting companies and number of attendees. The 2015 ACMG Annual ...
(Date:6/20/2016)... 2016 Securus Technologies, a leading provider ... public safety, investigation, corrections and monitoring announced that ... has secured the final acceptance by all three ... Access Systems (MAS) installed. Furthermore, Securus will have ... installed by October, 2016. MAS distinguishes between legitimate ...
Breaking Biology News(10 mins):
(Date:12/6/2016)... (PRWEB) , ... December 06, ... ... of the Almac Group, the world’s largest privately-held contract pharmaceutical development and ... inVentiv Health, a leading biopharma outsourcing company combining a leading CRO and ...
(Date:12/6/2016)... ... December 06, 2016 , ... Symbios Technologies, ... that the company has engaged in a collaborative research partnership with Colorado State ... CSU Office of the Vice President for Research. This agreement is designed to ...
(Date:12/6/2016)... , Dec. 6, 2016 Zimmer Biomet Holdings, ... announced the pricing terms of its previously-announced cash ... aggregate purchase price (excluding accrued and unpaid interest ... and excluding fees and expenses related to the ... securities identified in the table below (collectively, the ...
(Date:12/6/2016)... ... December 06, 2016 , ... RoviSys, a ... headquartered in Aurora, Ohio, announced the opening of their new office building today. ... constructed facility is home to 200 employees focused on providing sales, engineering, and ...
Breaking Biology Technology: