Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Prions offer nanotech building tool

01.04.2003


The same characteristics that make misfolded proteins known as prions such a pernicious medical threat in neurodegenerative diseases may offer a construction toolkit for manufacturing nanoscale electrical circuits, researchers report this week in the online edition of the Proceedings of the National Academy of Sciences.


Scientists working at Whitehead Institute for Biomedical Research and the University of Chicago write that they have used the durable, self-assembling fibers formed by prions as a template on which to deposit electricity-bearing gold and silver, creating electrical wire much thinner than it is possible to make by current mechanical processes.

"Most of the people working on nanocircuits are trying to build them using ’top-down’ fabrication techniques" used in conventional electrical engineering, explained Whitehead Institute Director Susan Lindquist, a co-author of the study. "We thought we’d try a ’bottom-up’ approach, and let molecular self-assembly do the hard work for us."

Construction of nanoscale microcircuits and machines is one of the highly prized goals of nanotechnology. Manufacturing is very tricky at this scale – a nanometer is one-billionth of a meter; a nanometer is to a meter what a small grape would be to the entire Earth. Moreover, these devices depend on nanowires to conduct electricity. So far, the mass production of these tiny wires has stymied researchers. Making very small computers and optical switches, or even biomedical devices that could be inserted into the body, could open up whole new fields of computation and medicine.



Lindquist and her colleagues took a different approach. Rather than building the metal wire itself, they let prions build a very thin fibrous template and then coaxed gold and silver to bond to the protein fibers. By themselves, the fibers are insulators; they can’t conduct electricity. But when coated with gold and silver particles, they became remarkably effective electrical wires.

The choice of prions to build this template was a natural one for Lindquist and her colleagues at the University of Chicago, where she started work on this project before joining Whitehead Institute. Proteins are the cell’s workhorses, and they need to fold into complex and precise shapes to do their jobs. Prions are misfolded proteins – rather like an origami swan that comes out looking and acting instead like an ostrich.

Prions have another characteristic that makes them ideal for the mass-manufacturing jobs researchers have in mind: They recruit other, properly folded proteins into misforming along with them, a process Lindquist calls a "conformational cascade" that ends up producing more and more ostriches instead of swans.

In the test tube, conformational cascade generates strings and strings of tough, durable and heat-resistant protein fibers of a type known as "amyloid". In humans, amyloids are best known as the plaque that gunks up neurons in people with Alzheimer’s, mad cow disease and other neurodegenerative illnesses. This may be one reason why these diseases are so resistant to treatment. However, yeast prions used as the source of protein in these experiments are completely harmless, making them safe to work with in manufacturing.

Lindquist and colleagues used a special genetic variant of yeast they modified to produce fibers capable of bonding with gold particles. They then coated these fiber strings with enough metal to make a working electrical wire.

In all important respects, these nanowires possess the characteristics of conventional solid metal wire, Lindquist explained, such as low resistance to electrical current.

"With materials like these," she noted, "it should be possible to harness the extraordinary diversity and specificity of protein functions to nanoscale electrical circuitry."


The research was supported by the National Institutes of Health, the W.M. Keck Foundation, the University of Chicago Materials Research Science and Engineering Center (MRSEC program of the NSF), the Howard Hughes Medical Institute and a postdoctoral fellowship of the Deutsche Forschungsgemeinschaft (T.S.).




Rick Borchelt | EurekAlert!

More articles from Materials Sciences:

nachricht Epoxy compound gets a graphene bump
14.11.2018 | Rice University

nachricht Automated adhesive film placement and stringer integration for aircraft manufacture
15.11.2018 | Fraunhofer IFAM

All articles from Materials Sciences >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: A Chip with Blood Vessels

Biochips have been developed at TU Wien (Vienna), on which tissue can be produced and examined. This allows supplying the tissue with different substances in a very controlled way.

Cultivating human cells in the Petri dish is not a big challenge today. Producing artificial tissue, however, permeated by fine blood vessels, is a much more...

Im Focus: A Leap Into Quantum Technology

Faster and secure data communication: This is the goal of a new joint project involving physicists from the University of Würzburg. The German Federal Ministry of Education and Research funds the project with 14.8 million euro.

In our digital world data security and secure communication are becoming more and more important. Quantum communication is a promising approach to achieve...

Im Focus: Research icebreaker Polarstern begins the Antarctic season

What does it look like below the ice shelf of the calved massive iceberg A68?

On Saturday, 10 November 2018, the research icebreaker Polarstern will leave its homeport of Bremerhaven, bound for Cape Town, South Africa.

Im Focus: Penn engineers develop ultrathin, ultralight 'nanocardboard'

When choosing materials to make something, trade-offs need to be made between a host of properties, such as thickness, stiffness and weight. Depending on the application in question, finding just the right balance is the difference between success and failure

Now, a team of Penn Engineers has demonstrated a new material they call "nanocardboard," an ultrathin equivalent of corrugated paper cardboard. A square...

Im Focus: Coping with errors in the quantum age

Physicists at ETH Zurich demonstrate how errors that occur during the manipulation of quantum system can be monitored and corrected on the fly

The field of quantum computation has seen tremendous progress in recent years. Bit by bit, quantum devices start to challenge conventional computers, at least...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

VideoLinks
Industry & Economy
Event News

“3rd Conference on Laser Polishing – LaP 2018” Attracts International Experts and Users

09.11.2018 | Event News

On the brain’s ability to find the right direction

06.11.2018 | Event News

European Space Talks: Weltraumschrott – eine Gefahr für die Gesellschaft?

23.10.2018 | Event News

 
Latest News

Massive impact crater from a kilometer-wide iron meteorite discovered in Greenland

15.11.2018 | Earth Sciences

When electric fields make spins swirl

15.11.2018 | Physics and Astronomy

Discovery of a cool super-Earth

15.11.2018 | Physics and Astronomy

VideoLinks
Science & Research
Overview of more VideoLinks >>>