Nanotechnology Now







Heifer International

Wikipedia Affiliate Button


DHgate

Home > Press > Great expectations: When will artificial molecular machines start working for us?

Abstract:
Physicist Richard Feynman in his famous 1959 talk, "Plenty of Room at the Bottom," described the precise control at the atomic level promised by molecular machines of the future. More than 50 years later, synthetic molecular switches are a dime a dozen, but synthetically designed molecular machines are few and far between.

Great expectations: When will artificial molecular machines start working for us?

Chicago, IL | Posted on November 26th, 2011

Northwestern University chemists recently teamed up with a University of Maine physicist to explore the question, "Can artificial molecular machines deliver on their promise?" Their provocative analysis provides a roadmap outlining future challenges that must be met before full realization of the extraordinary promise of synthetic molecular machines can be achieved.

The tutorial review will be published Nov. 25 by the journal Chemical Society Reviews.

The senior authors are Sir Fraser Stoddart, Board of Trustees Professor of Chemistry, and Bartosz A. Grzybowski, the K. Burgess Professor of Physical Chemistry, both in Northwestern's Weinberg College of Arts and Sciences, and Dean Astumian, professor of physics at the University of Maine. (Grzybowski is also professor of chemical and biological engineering in the McCormick School of Engineering and Applied Science.)

One might ask, what is the difference between a switch and a machine at the level of a molecule? It all comes down to the molecule doing work.

"A simplistic analogy of an artificial molecular switch is the piston in a car engine while idling," explains Ali Coskun, lead author of the paper and a postdoctoral fellow in Stoddart's laboratory. "The piston continually switches between up and down, but the car doesn't go anywhere. Until the pistons are connected to a crankshaft that, in turn, makes the car's wheels turn, the switching of the pistons only wastes energy without doing useful work."

Astumian points out that this analogy only takes us part of the way to understanding molecular machines. "All nanometer-scale machines are subject to continual bombardment by the molecules in their environment giving rise to what is called 'thermal noise,'" he cautions. "Attempts to mimic macroscopic approaches to achieve precisely controlled machines by minimizing the effects of thermal noise have not been notably successful."

Scientists currently are focused on a chemical approach where thermal noise is exploited for constructive purposes. Thermal "activation" is almost certainly at the heart of the mechanisms by which biomolecular machines in our cells carry out the essential tasks of metabolism. "At the nanometer scale of single molecules, harnessing energy is as much about preventing unwanted, backward motion as it is about causing forward motion," Astumian says.

In order to fulfill their great promise, artificial molecular machines need to operate at all scales. A single molecular switch interfaced to its environment can do useful work only on its own tiny scale, perhaps by assembling small molecules into chemical products of great complexity. But what about performing tasks in the macroscopic world?

To achieve this goal, "there is a need to organize the molecular switches spatially and temporally, just as in nature," Stoddart explains. He suggests that "metal-organic frameworks may hold the key to this particular challenge on account of their robust yet highly integrated architectures."

What is really encouraging is the remarkable energy-conversion efficiency of artificial molecular machines to perform useful work that can be greater than 75 percent. This efficiency is quite spectacular when compared to the efficiency of typical car engines, which convert only 20 to 30 percent of the chemical energy of gasoline into mechanical work, or even of the most efficient diesel engines with efficiencies of 50 percent.

"The reason for this high efficiency is that chemical energy can be converted directly into mechanical work, without having to be first converted into heat," Grzybowski says. "The possible uses of artificial molecular machines raise expectations expressed in the fact that the first person to create a nanoscale robotic arm, which shows precise positional control of matter at the nanoscale, can claim Feynman's Grand Prize of $250,000."

The title of the paper is "Great Expectations: Can Artificial Molecular Machines Deliver on Their Promise?" In addition to Stoddart, Grzybowski, Coskun and Astumian, the other co-author of the paper is Michal Banaszak from Adam Mickiewicz University, Poland.

####

For more information, please click here

Contacts:
Megan Fellman

847-491-3115

Copyright © Northwestern University

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

News and information

SEFCU, SUNY Poly CNSE Announce Winning Student-Led Teams in the 6th Annual $500,000 New York Business Plan Competition April 25th, 2015

Northwestern scientists develop first liquid nanolaser: Technology could lead to new way of doing 'lab on a chip' medical diagnostics April 25th, 2015

Nanotech-enabled moisturizer speeds healing of diabetic skin wounds: Spherical nucleic acids silence gene that interferes with wound healing April 24th, 2015

Fast and accurate 3-D imaging technique to track optically trapped particles April 24th, 2015

Chemistry

Scientists Use Nanoscale Building Blocks and DNA 'Glue' to Shape 3D Superlattices: New approach to designing ordered composite materials for possible energy applications April 23rd, 2015

New class of 3D-printed aerogels improve energy storage April 22nd, 2015

Expanding the reach of metallic glass April 22nd, 2015

Protein Building Blocks for Nanosystems: Scientists develop method for producing bio-based materials with new properties April 17th, 2015

Possible Futures

Printing Silicon on Paper, with Lasers April 21st, 2015

A glass fiber that brings light to a standstill: By coupling photons to atoms, light in a glass fiber can be slowed down to the speed of an express train; for a short while it can even be brought to a complete stop April 9th, 2015

Nanotechnology in Medical Devices Market is expected to reach $8.5 Billion by 2019 March 25th, 2015

Nanotechnology Enabled Drug Delivery to Influence Future Diagnosis and Treatments of Diseases March 21st, 2015

Molecular Machines

UCLA nanoscientists are first to model atomic structures of three bacterial nanomachines: Cryo electron microscope enables scientists to explore the frontiers of targeted antibiotics April 21st, 2015

Advances in molecular electronics: Lights on -- molecule on: Researchers from Dresden and Konstanz succeed in light-controlled molecule switching April 20th, 2015

Designer's toolkit for dynamic DNA nanomachines: Arm-waving nanorobot signals new flexibility in DNA origami March 27th, 2015

Tiny bio-robot is a germ suited-up with graphene quantum dots March 24th, 2015

Announcements

SEFCU, SUNY Poly CNSE Announce Winning Student-Led Teams in the 6th Annual $500,000 New York Business Plan Competition April 25th, 2015

Northwestern scientists develop first liquid nanolaser: Technology could lead to new way of doing 'lab on a chip' medical diagnostics April 25th, 2015

Nanotech-enabled moisturizer speeds healing of diabetic skin wounds: Spherical nucleic acids silence gene that interferes with wound healing April 24th, 2015

Fast and accurate 3-D imaging technique to track optically trapped particles April 24th, 2015

Grants/Awards/Scholarships/Gifts/Contests/Honors/Records

SEFCU, SUNY Poly CNSE Announce Winning Student-Led Teams in the 6th Annual $500,000 New York Business Plan Competition April 25th, 2015

Richards-Kortum elected to American Academy of Arts and Sciences: April 22nd, 2015

‘Oxford Instruments Young Nanoscientist India Award 2015’ to Prof. Arindam Ghosh April 20th, 2015

Iranian Female Professor Awarded UNESCO Medal in Nanoscience April 20th, 2015

Research partnerships

Pseudoparticles travel through photoactive material: KIT scientists measure important process in the conversion of light energy -- publication in Nature Communications April 24th, 2015

Electron spin brings order to high entropy alloys April 23rd, 2015

Surface matters: Huge reduction of heat conduction observed in flat silicon channels April 23rd, 2015

Drexel materials scientists putting a new spin on computing memory April 22nd, 2015

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