Nanotechnology Now

Our NanoNews Digest Sponsors





Heifer International

Wikipedia Affiliate Button


android tablet pc

Home > Press > Team Develops New Method for Creating Self-Assembling, Nanoscale Materials

The new material created by the Scripps Research team used phage nanotubes (electron microscope image in the background) to make a novel polymer (cube shown here), which displayed remarkable flexibility. Interestingly, theoretical calculations had predicted how the material would pack together using the least amount of energy, as modeled by the colored helix.
The new material created by the Scripps Research team used phage nanotubes (electron microscope image in the background) to make a novel polymer (cube shown here), which displayed remarkable flexibility. Interestingly, theoretical calculations had predicted how the material would pack together using the least amount of energy, as modeled by the colored helix.

Abstract:
While biomedical, electronics, and other branches of research are marching steadily into the realm of the smaller-than-small nanometer scale, building needed materials at this scale has been problematic.

Team Develops New Method for Creating Self-Assembling, Nanoscale Materials

La Jolla, CA | Posted on January 30th, 2008

This week, however, a team from The Scripps Research Institute unveiled a novel approach to the problem that yields a material with novel properties, which some might find reminiscent of Flubber. The material is produced using naturally occurring proteins as templates for uniform, self-assembled, nano-scale construction.

The material, an organic polymer described in the January 23 online, early edition of the Proceedings of the National Academy of Sciences (PNAS), could one day find application in everything from screening for disease to microelectronics.
Using Nature's Tricks

Nature is replete with examples of molecules such as DNA that self-assemble with uniform patterns on the nanoscale, but until now researchers have had limited success duplicating such processes. The new study, however, provides one synthetic method that has effectively mimicked the templating strategy used in nature for nanoscale construction in the lab.

To create the new material, the Scripps Research team, led by Scripps Research President Richard Lerner and Assistant Professor Tobin Dickerson, began with a natural nanoscale product, a bacterial virus or phage. A nanometer is one billionth of a meter, or the width of a few average atoms.

Specifically, the product the team worked with was a phage known as M13. If scaled up, the phage is proportionally equivalent to a 4-foot-long pencil, with the tip and eraser roughly representing the active parts of the phage that infect bacteria. Other proteins that are biologically inert and analogous to the wood body of the pencil provide the filamentous phage's structure.

Having worked with phage extensively in other applications, the team decided to explore the possibility of using those structural proteins as a potential template for nanoscale construction. To do so, the team chemically modified molecular protrusions on the proteins so they would attract and bind with the components needed to form strands of polyacrylamide, a common polymer used to make laboratory gels.

The resulting polymer-phage combination, which twists into helices like DNA and RNA molecules, takes on the shape of a comb with the polymers as the teeth. These teeth in turn interlock to form a strangely resilient, rubbery solid.
Shocking Flexibility

Once the new material, known as a protein-polymer bioconjugate, was created, the group was shocked to find that it was almost impossible to break a sample apart. It could be sliced, but no matter how hard researchers compressed or squeezed it, it always bounced back to its original state, because the stable phage proteins act like rebar in concrete to provide strength.

Further analyses uncovered additional important characteristics. The combs do not grow completely uniformly—some combs grow more teeth than others, for instance, before interlocking with a nearby comb. But the combs can only be a prescribed distance apart for the chemical interlocking to occur, which leads to uniform size for the pores between the comb teeth. The pores proved to be about 4 nanometers wide and greater than 1 micrometer (one millionth of a meter) in length.

This uniformity is in stark contrast with experiments which showed that simply mixing the phages with polymers without the templating procedure produces a chaotic hodge podge at the molecular level.

Interestingly, after creating the material, the group discovered that a British scientist had done theoretical calculations about how flexible rods—like the phages—would pack together using the least amount of energy.

"It was extremely gratifying to see that the mathematics had exactly predicted what we were observing," says Dickerson.
Putting It to Use

Although the work was intended mainly as a proof of concept for using the phages as templates, the researchers have a number of potential applications in mind. The phage can be produced easily and cheaply in very large quantities, and the polymer components are readily available and simple to combine to create the final material. These characteristics would make commercial application possible.

"In essence, bacteriophage-derived materials are a renewable resource," says Dickerson.

The defined channels established by the pores in the material might be adapted as pathways for electrons for use in microelectronics. Or, the pores might be used as a filter for certain molecules, for example to test blood samples for proteins whose presence is tied to particular diseases. More complex potential uses might include altering the biologically active portions of the phage to attract specific molecules, forcing them into the polymers' pores, or to block others.

"These tools can be visualized like Tinkertoys ® or Legos ®," says Dickerson of the possibilities. "You can think about this really in engineering terms using macroscopic analogs such as baskets, or lids, or holes."

To add to the list of potential applications, the team has already begun exploring additional materials that might be created using the basic phage construction scheme.

In addition to Dickerson and Lerner, authors on the paper, entitled "Biologically templated organic polymers with nanoscale order," were Bert Willis, Lisa Eubanks, Malcolm Wood, and Kim Janda, all of Scripps Research. See http://www.pnas.org/cgi/content/abstract/0711308105v1.

The work was supported by the Skaggs Institute for Chemical Biology, Worm Institute for Research and Medicine, and a National Institutes of Health Kirschstein National Research Service Award.



Send comments to:

####

About The Scripps Research Institute
The Scripps Research Institute, one of the country's largest, private, non-profit research organizations, has always stood at the forefront of basic biomedical science, a vital segment of medical research that seeks to comprehend the most fundamental processes of life. In just three decades the Institute has established a lengthy track record of major contributions to the betterment of health and the human condition.

The Institute has become internationally recognized for its basic research into immunology, molecular and cellular biology, chemistry, neurosciences, autoimmune diseases, cardiovascular diseases, virology and synthetic vaccine development. Particularly significant is the Institute's study of the basic structure and design of biological molecules; in this arena TSRI is among a handful of the world's leading centers.

For more information, please click here

Copyright © The Scripps Research Institute

If you have a comment, please Contact us.

Issuers of news releases, not 7th Wave, Inc. or Nanotechnology Now, are solely responsible for the accuracy of the content.

Bookmark:
Delicious Digg Newsvine Google Yahoo Reddit Magnoliacom Furl Facebook

Related News Press

Self Assembly

NYU Researchers Break Nano Barrier to Engineer the First Protein Microfiber October 23rd, 2014

NIST offers electronics industry 2 ways to snoop on self-organizing molecules October 22nd, 2014

‘Designer’ nanodevice could improve treatment options for cancer sufferers October 22nd, 2014

Crystallizing the DNA nanotechnology dream: Scientists have designed the first large DNA crystals with precisely prescribed depths and complex 3D features, which could create revolutionary nanodevices October 20th, 2014

Nanobiotechnology

Tiny carbon nanotube pores make big impact October 29th, 2014

Molecular beacons shine light on how cells 'crawl' October 27th, 2014

Breakthrough in molecular electronics paves the way for DNA-based computer circuits in the future: DNA-based programmable circuits could be more sophisticated, cheaper and simpler to make October 27th, 2014

NYU Researchers Break Nano Barrier to Engineer the First Protein Microfiber October 23rd, 2014

NanoNews-Digest
The latest news from around the world, FREE





  Premium Products
NanoNews-Custom
Only the news you want to read!
 Learn More
NanoTech-Transfer
University Technology Transfer & Patents
 Learn More
NanoStrategies
Full-service, expert consulting
 Learn More














ASP
Nanotechnology Now Featured Books




NNN

The Hunger Project







© Copyright 1999-2014 7th Wave, Inc. All Rights Reserved PRIVACY POLICY :: CONTACT US :: STATS :: SITE MAP :: ADVERTISE