Nanotechnology Now

Our NanoNews Digest Sponsors

Heifer International

Wikipedia Affiliate Button

Home > Press > Livermore researchers use carbon nanotubes for molecular transport

FAST FLOW THROUGH CARBON NANOTUBES: The animation starts with the depiction of the water flow through a regular "rough" pipe. The molecules near the wall stick to it and move much slower than the molecules in the middle of the pipe. Colors indicate the speed of the molecules -- green are fast, yellow are slower, red are the slowest.
The rough pipe fades and the carbon nanotube appears. All the molecules in the carbon nanotube move fast (green). They do not stick to the surface of the nanotube because that surface is very slippery. The water molecules travel in chains because they interact with each other strongly via hydrogen bonds. These two effects (the slippery nanotube surface and formation of water molecule chains inside the nanotube) combine to produce this phenomenon of ultra-fast flow through carbon nanotubes.
Animation by Kwei-Yu Chu/LLNL - https://publicaffairs.llnl.gov/news/news_releases/2008/NR-08-06-03.html
FAST FLOW THROUGH CARBON NANOTUBES: The animation starts with the depiction of the water flow through a regular "rough" pipe. The molecules near the wall stick to it and move much slower than the molecules in the middle of the pipe. Colors indicate the speed of the molecules -- green are fast, yellow are slower, red are the slowest. The rough pipe fades and the carbon nanotube appears. All the molecules in the carbon nanotube move fast (green). They do not stick to the surface of the nanotube because that surface is very slippery. The water molecules travel in chains because they interact with each other strongly via hydrogen bonds. These two effects (the slippery nanotube surface and formation of water molecule chains inside the nanotube) combine to produce this phenomenon of ultra-fast flow through carbon nanotubes.
Animation by Kwei-Yu Chu/LLNL - https://publicaffairs.llnl.gov/news/news_releases/2008/NR-08-06-03.html

Abstract:
Molecular transport across cellular membranes is essential to many of life's processes, for example electrical signaling in nerves, muscles and synapses.

In biological systems, the membranes often contain a slippery inner surface with selective filter regions made up of specialized protein channels of sub-nanometer size. These pores regulate cellular traffic, allowing some of the smallest molecules in the world to traverse the membrane extremely quickly, while at the same time rejecting other small molecules and ions.

Livermore researchers use carbon nanotubes for molecular transport

LIVERMORE, CA | Posted on June 9th, 2008

Researchers at Lawrence Livermore National Laboratory are mimicking that process with manmade carbon nanotube membranes, which have pores that are 100,000 times smaller than a human hair, and were able to determine the rejection mechanism within the pores.

"Hydrophobic, narrow diameter carbon nanotubes can provide a simplified model of membrane channels by reproducing these critical features in a simpler and more robust platform," said Olgica Bakajin, who led the LLNL team whose study appeared in the June 6 online edition of the journal Proceedings of the National Academy of Sciences.

In the initial discovery, reported in the May 19, 2006 issue of the journal Science, the LLNL team found that water molecules in a carbon nanotube move fast and do not stick to the nanotube's super smooth surface, much like water moves through biological channels. The water molecules travel in chains - because they interact with each other strongly via hydrogen bonds.

"You can visualize it as mini-freight trains of chain-bonded water molecules flying at high speed through a narrow nanotube tunnel," said Hyung Gyu Park, an LLNL postdoctoral researcher and a team member.

One of the most promising applications for carbon nanotube membranes is sea water desalination. These membranes will some day be able to replace conventional membranes and greatly reduce energy use for desalination.

In the recent study, the researchers wanted to find out if the membranes with 1.6 nanometer (nm) pores reject ions that make up common salts. In fact, the pores did reject the ions and the team was able to understand the rejection mechanism.

"Our study showed that pores with a diameter of 1.6nm on the average, the salts get rejected due to the charge at the ends of the carbon nanotubes," said Francesco Fornasiero, an LLNL postdoctoral researcher, team member and the study's first author

Fast flow through carbon nanotube pores makes nanotube membranes more permeable than other membranes with the same pore sizes. Yet, just like conventional membranes, nanotube membranes exclude ions and other particles due to a combination of small pore size and pore charge effects.

"While carbon nanotube membranes can achieve similar rejection as membranes with similarly sized pores, they will provide considerably higher permeability, which makes them potentially much more efficient than the current generation of membranes," said Aleksandr Noy, a senior member of the LLNL team.

Researchers will be able to build better membranes when they can independently change pore diameter, charge and material that fills gaps between carbon nanotubes.

####

About Lawrence Livermore National Laboratory
Founded in 1952, Lawrence Livermore National Laboratory is a national security laboratory, with a mission to ensure national security and apply science and technology to the important issues of our time. Lawrence Livermore National Laboratory is managed by Lawrence Livermore National Security, LLC for the U.S. Department of Energy's National Nuclear Security Administration.

For more information, please click here

Contacts:
Anne M. Stark
(925) 422-9799

Copyright © Lawrence Livermore National Laboratory

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

Thanks for the memory: NIST takes a deep look at memristors January 20th, 2018

New Method Uses DNA, Nanoparticles and Top-Down Lithography to Make Optically Active Structures: Technique could lead to new classes of materials that can bend light, such as for those used in cloaking devices January 18th, 2018

Arrowhead Pharmaceuticals Announces Pricing of Underwritten Public Offering of Common Stock January 18th, 2018

Leti to Demo New Curving Technology at Photonics West that Improves Performance of Optical Components January 18th, 2018

Videos/Movies

Nanotube fibers in a jiffy: Rice University lab makes short nanotube samples by hand to dramatically cut production time January 11th, 2018

Development of a nanowire device to detect cancer with a urine test December 26th, 2017

Nanotubes go with the flow to penetrate brain tissue: Rice University scientists, engineers develop microfluidic devices, microelectrodes for gentle implantation December 19th, 2017

Quantum memory with record-breaking capacity based on laser-cooled atoms December 15th, 2017

Nanotubes/Buckyballs/Fullerenes/Nanorods

Nanotube fibers in a jiffy: Rice University lab makes short nanotube samples by hand to dramatically cut production time January 11th, 2018

Touchy nanotubes work better when clean: Rice, Swansea scientists show that decontaminating nanotubes can simplify nanoscale devices January 4th, 2018

Paving the way for a non-electric battery to store solar energy: UMass Amherst scientists say a polymer chain organized like a string of Christmas lights assists energy storage December 22nd, 2017

Nanotubes go with the flow to penetrate brain tissue: Rice University scientists, engineers develop microfluidic devices, microelectrodes for gentle implantation December 19th, 2017

Discoveries

Thanks for the memory: NIST takes a deep look at memristors January 20th, 2018

New Method Uses DNA, Nanoparticles and Top-Down Lithography to Make Optically Active Structures: Technique could lead to new classes of materials that can bend light, such as for those used in cloaking devices January 18th, 2018

Nanowrinkles could save billions in shipping and aquaculture Surfaces inspired by carnivorous plants delay degradation by marine fouling January 17th, 2018

Ultrathin black phosphorus for solar-driven hydrogen economy: Osaka University researchers use sunlight to make hydrogen with a new nanostructured catalyst based on nanosheets of black phosphorus and bismuth vanadate January 17th, 2018

Announcements

Thanks for the memory: NIST takes a deep look at memristors January 20th, 2018

New Method Uses DNA, Nanoparticles and Top-Down Lithography to Make Optically Active Structures: Technique could lead to new classes of materials that can bend light, such as for those used in cloaking devices January 18th, 2018

Arrowhead Pharmaceuticals Announces Pricing of Underwritten Public Offering of Common Stock January 18th, 2018

Leti to Demo New Curving Technology at Photonics West that Improves Performance of Optical Components January 18th, 2018

Water

Rice U.'s one-step catalyst turns nitrates into water and air: NSF-funded NEWT Center aims for catalytic converter for nitrate-polluted water January 5th, 2018

A new way to mix oil and water: Condensation-based method developed at MIT could create stable nanoscale emulsions November 8th, 2017

Magnetized viruses attack harmful bacteria: Rice, China team uses phage-enhanced nanoparticles to kill bacteria that foul water treatment systems August 2nd, 2017

Bacteria-coated nanofiber electrodes clean pollutants in wastewater July 1st, 2017

Nanobiotechnology

New Method Uses DNA, Nanoparticles and Top-Down Lithography to Make Optically Active Structures: Technique could lead to new classes of materials that can bend light, such as for those used in cloaking devices January 18th, 2018

Arrowhead Pharmaceuticals Announces Pricing of Underwritten Public Offering of Common Stock January 18th, 2018

Ultra-thin optical fibers offer new way to 3-D print microstructures: Novel approach lays groundwork for using 3-D printing to repair tissue in the body January 17th, 2018

Arrowhead Pharmaceuticals Announces Proposed Underwritten Offering of Common Stock January 17th, 2018

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