Featured Research

from universities, journals, and other organizations

Chemists Report The Most Sophisticated Artificial Nanomachine Yet

Date:
March 24, 2004
Source:
University Of California, Los Angeles
Summary:
UCLA supramolecular chemists report in the journal Science an artificial molecular machine that functions like a nanoelevator.

UCLA supramolecular chemists report in the journal Science an artificial molecular machine that functions like a nanoelevator.

"Such nanoscale robotic devices could find use in slow-release drug delivery systems and in the control of chemical reactions within nanofluidic systems conducted in laboratories on a chip," said Jovica Badjic, the lead author of the March 19 Science article and postdoctoral researcher in the laboratory of Fraser Stoddart, holder of the Fred Kavli Chair in nanosystems sciences and director of the California NanoSystems Institute at UCLA.

In Badjic's incrementally staged design of the nanoelevator — a rig-like construct with three legs embracing an interlocked deck-like component — can be made to move between two levels, he had to get the matching components to fit together just perfectly.

The challenge is similar to one that nature has already solved in creating the multivalent interactions that exist between cells for the purpose of communicating information throughout the body.

"The first step in the synthesis can be likened to learning how to put a glove on one's hand blindfolded. You will make countless mistakes but eventually you find out by trial and error how to get the match just right. That's how the multivalency gets expressed during my template-directed synthesis," Badjic said.

In order to demonstrate the operation of the elevator, the UCLA chemists entered into collaboration with an Italian team at the University of Bologna: professor Vincenzo Balzani, assistant professor Alberto Credi and graduate student Serena Silvi.

The elevator is about 3.5 nanometers in diameter and 2.5 nanometers in height. Each leg of the rig has two stations — one, a strong one, which relies on hydrogen bonds, and another much weaker one. The strong hydrogen bonds between the rig and the deck can be destroyed by taking a proton away from each leg one at a time with base. The result is a stepwise movement of the deck down to the now preferred stations lower down the rig. By taking steps one at a time, the elevator is more reminiscent of a legged animal than it is of a passenger elevator. The deck can be returned to the top level by the addition of acid. The elevator has been made to go up and down 10 times by the consecutive addition of acid and base, respectively.

Although it has been commented in the article that distance traveled by the deck is just a little less than one nanometer — 1,000 times smaller than the thickness of a human hair — and that the force generated could be as much as 200 picoNewtons, Stoddart urged caution with respect to this claim, based on calculations carried out in Bologna, until it is backed up by experiments, and also by an all-encompassing theory.

A common theme of Stoddart's research is the quest for a better fundamental understanding of self-assembly and molecular recognition processes in chemical systems. He has been working for more than a quarter of a century on using this growing understanding to develop template-directed protocols that rely upon such processes to create molecular switches and motor-molecules. Underlying his bottom-up approach to the construction of functioning nanosystems is Stoddart's philosophy of transferring concepts from biology into chemistry.

Despite the rarefied scientific atmosphere, Stoddart's highly specialized world might be more akin to that of an engineer or an artist than a scientist. In fact, in his quest to create mechanoelectrochemical systems, Stoddart likens himself to the painter who creates abstracts, rather than one who produces landscapes and portraits.

"Constructing artificial molecular machines is a pursuit that allows the chemist to enter the world of the engineer," Stoddart said. It is not an area of research for the faint-hearted. Many chemists and engineers have their misgivings about where all the effort is going to lead to in the fullness of time. Stoddart's answer to the skeptics is to draw a comparison between natural and unnatural systems using the action of flight.

Birds, bees and bats have been flying around for a long time. It is only in the past 100 years that humankind has learned how to fly. Prior to the first demonstration of manned flight, there were many great scientists and engineers who said it was impossible.

"Building artificial molecular machines and getting them to operate is where airplanes were a century ago," Stoddart said. "We have come a long way in the last decade, but we have a very, very long way to go yet to realize the full potential of artificial molecular machines."

"The main reason for doing this kind of nanoscience is that it is intellectually and technically challenging," said Badjic, who was one of five recipients March 17 of a UCLA Chancellor's Award for Postdoctoral Research.


Story Source:

The above story is based on materials provided by University Of California, Los Angeles. Note: Materials may be edited for content and length.


Cite This Page:

University Of California, Los Angeles. "Chemists Report The Most Sophisticated Artificial Nanomachine Yet." ScienceDaily. ScienceDaily, 24 March 2004. <www.sciencedaily.com/releases/2004/03/040323074844.htm>.
University Of California, Los Angeles. (2004, March 24). Chemists Report The Most Sophisticated Artificial Nanomachine Yet. ScienceDaily. Retrieved October 21, 2014 from www.sciencedaily.com/releases/2004/03/040323074844.htm
University Of California, Los Angeles. "Chemists Report The Most Sophisticated Artificial Nanomachine Yet." ScienceDaily. www.sciencedaily.com/releases/2004/03/040323074844.htm (accessed October 21, 2014).

Share This



More Matter & Energy News

Tuesday, October 21, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Graphene Paint Offers Rust-Free Future

Graphene Paint Offers Rust-Free Future

Reuters - Innovations Video Online (Oct. 21, 2014) British scientists have developed a prototype graphene paint that can make coatings which are resistant to liquids, gases, and chemicals. The team says the paint could have a variety of uses, from stopping ships rusting to keeping food fresher for longer. Jim Drury reports. Video provided by Reuters
Powered by NewsLook.com
Gulfstream G500, G600 Unveiling

Gulfstream G500, G600 Unveiling

Flying (Oct. 20, 2014) Watch Gulfstream's public launch of the G500 and G600 at their headquarters in Savannah, Ga., along with a surprise unveiling of the G500, which taxied up under its own power. Video provided by Flying
Powered by NewsLook.com
Japanese Scientists Unveil Floating 3D Projection

Japanese Scientists Unveil Floating 3D Projection

Reuters - Innovations Video Online (Oct. 20, 2014) Scientists in Tokyo have demonstrated what they say is the world's first 3D projection that floats in mid air. A laser that fires a pulse up to a thousand times a second superheats molecules in the air, creating a spark which can be guided to certain points in the air to shape what the human eye perceives as an image. Matthew Stock reports. Video provided by Reuters
Powered by NewsLook.com
Hey, Doc! Sewage, Beer and Food Scraps Can Power Chevrolet’s Bi-Fuel Impala

Hey, Doc! Sewage, Beer and Food Scraps Can Power Chevrolet’s Bi-Fuel Impala

3BL Media (Oct. 20, 2014) Hey, Doc! Sewage, Beer and Food Scraps Can Power Chevrolet’s Bi-fuel Impala Video provided by 3BL
Powered by NewsLook.com

Search ScienceDaily

Number of stories in archives: 140,361

Find with keyword(s):
Enter a keyword or phrase to search ScienceDaily for related topics and research stories.

Save/Print:
Share:

Breaking News:

Strange & Offbeat Stories


Space & Time

Matter & Energy

Computers & Math

In Other News

... from NewsDaily.com

Science News

Health News

Environment News

Technology News



Save/Print:
Share:

Free Subscriptions


Get the latest science news with ScienceDaily's free email newsletters, updated daily and weekly. Or view hourly updated newsfeeds in your RSS reader:

Get Social & Mobile


Keep up to date with the latest news from ScienceDaily via social networks and mobile apps:

Have Feedback?


Tell us what you think of ScienceDaily -- we welcome both positive and negative comments. Have any problems using the site? Questions?
Mobile: iPhone Android Web
Follow: Facebook Twitter Google+
Subscribe: RSS Feeds Email Newsletters
Latest Headlines Health & Medicine Mind & Brain Space & Time Matter & Energy Computers & Math Plants & Animals Earth & Climate Fossils & Ruins