Nanotechnology Now

Our NanoNews Digest Sponsors





Heifer International

Wikipedia Affiliate Button


android tablet pc

Home > Press > Fluorescent Nanotubes Illuminate the Inner Workings of Laboratory Mice

Abstract:
Developing drugs to combat or cure human disease often involves a phase of testing with mice, so being able to peer clearly into a living mouse's innards has real value. But with the fluorescent dyes currently used to image the interior of laboratory mice, the view becomes murky a few millimeters under the skin. Now, however, a team of investigators from Stanford University has developed an improved imaging method using fluorescent carbon nanotubes that create color images centimeters beneath the skin with far more clarity than conventional dyes provide. For a creature the size of a mouse, a few centimeters makes a great difference.

Fluorescent Nanotubes Illuminate the Inner Workings of Laboratory Mice

Bethesda, MD | Posted on June 27th, 2011

"We have already used similar carbon nanotubes to deliver drugs to treat cancer in laboratory testing in mice, but you would like to know where your delivery went, right?" said Stanford University's Hongjie Dai, a member of the National Cancer Institute's Alliance for Nanotechnology in Cancer. "With the fluorescent nanotubes, we can do drug delivery and imaging simultaneously - in real time - to evaluate the accuracy of a drug in hitting its target." Dr. Dai and his collaborators published their findings in the Proceedings of the National Academy of Sciences.

Dr. Dai's team injects the single-walled carbon nanotubes into a mouse and then watches as the tubes are delivered to internal organs by the bloodstream. The nanotubes fluoresce brightly in response to the light of a laser directed at the mouse, while a camera attuned to the nanotubes' near-infrared wavelengths records the images. By attaching the nanotubes to an anticancer agent, researchers can see how the drug is progressing through the mouse's body.

The key to the nanotubes' usefulness is that they shine in a different portion of the near-infrared spectrum than most dyes. Biological tissues - whether mouse or human - naturally fluoresce at wavelengths below 900 nanometers, which is in the same range as the available biocompatible organic fluorescent dyes. That results in undesirable background fluorescence, which muddles the images when dyes are used. But the nanotubes used by Dai's group fluoresce at wavelengths between 1,000 and 1,400 nanometers.¬ There is barely any natural tissue fluorescence at those wavelengths, so background "noise" is minimal.

The nanotubes' usefulness is further boosted because tissue scatters less light in the longer wavelength region of the near-infrared, reducing image smearing as light moves or travels through the body. "The nanotubes fluoresce naturally, but they emit in a very oddball region," Dr. Dai said. "There are not many things - living or inert - that emit in this region, which is why it has not been explored very much for biological imaging." By selecting single-walled carbon nanotubes with different diameters and other properties, Dr. Dai and his team can fine-tune the wavelength at which the nanotubes fluoresce.

The nanotubes can be seen immediately upon injection into the bloodstream of mice. In fact, the Stanford team was able to see the fluorescent nanotubes passing through the lungs and kidneys within seconds of injection.¬ The spleen and liver lit up a few seconds later. "You can really see things that are deep inside or blocked by other organs such as the pancreas," Dr. Dai said.

There are other imaging methods that can produce deep tissue images, such as magnetic resonance imaging (MRI) and computer tomography (CT) scans, but fluorescence imaging is widely used in research and requires simpler machinery. Dr. Dai said that the fluorescent nanotubes are not capable of reaching the depth of CT or MRI scans, but represent a step forward in broadening the potential uses of fluorescence as an imaging system beyond the surface and near-surface. "I did not imagine [carbon nanotubes] could really be used in animals to get deep images like these," he said. "When you look at images like this, you get a sense that the body almost has some transparency to it."

####

About The National Cancer Institute (NCI)
To help meet the goal of reducing the burden of cancer, the National Cancer Institute (NCI), part of the National Institutes of Health, is engaged in efforts to harness the power of nanotechnology to radically change the way we diagnose, treat and prevent cancer.

The NCI Alliance for Nanotechnology in Cancer is a comprehensive, systematized initiative encompassing the public and private sectors, designed to accelerate the application of the best capabilities of nanotechnology to cancer.

Currently, scientists are limited in their ability to turn promising molecular discoveries into benefits for cancer patients. Nanotechnology can provide the technical power and tools that will enable those developing new diagnostics, therapeutics, and preventives to keep pace with todayís explosion in knowledge.

For more information, please click here

Contacts:
National Cancer Institute
Office of Technology & Industrial Relations
ATTN: NCI Alliance for Nanotechnology in Cancer
Building 31, Room 10A49
31 Center Drive , MSC 2580
Bethesda , MD 20892-2580

Copyright © The National Cancer Institute (NCI)

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 Links

View abstract - "Deep-tissue anatomical imaging of mice using carbon nanotube fluorophores in the second near-infrared window."

Related News Press

News and information

Iran to Hold 3rd Int'l Engineering Materials, Metallurgy Conference October 25th, 2014

Haydale Secures Exclusive Development and Supply Agreement with Tantec A/S: New reactors to be built and commissioned by Tantec A/S represent another step forward towards the commercialisation of graphene October 24th, 2014

QuantumWise guides the semiconductor industry towards the atomic scale October 24th, 2014

SUNY Polytechnic Institute Invites the Public to Attend its Popular Statewide 'NANOvember' Series of Outreach and Educational Events October 23rd, 2014

Strengthening thin-film bonds with ultrafast data collection October 23rd, 2014

Imaging

National Synchrotron Light Source II Achieves 'First Light' October 23rd, 2014

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

Govt.-Legislation/Regulation/Funding/Policy

Novel Rocket Design Flight Tested: New Rocket Propellant and Motor Design Offers High Performance and Safety October 23rd, 2014

Strengthening thin-film bonds with ultrafast data collection October 23rd, 2014

Brookhaven Lab Launches Computational Science Initiative:Leveraging computational science expertise and investments across the Laboratory to tackle "big data" challenges October 22nd, 2014

Bipolar Disorder Discovery at the Nano Level: Tiny structures found in brain synapses help scientists better understand disorder October 22nd, 2014

Nanomedicine

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

Iranian Scientists Apply Nanotechnology to Produce Surgery Suture October 23rd, 2014

RF Heating of Magnetic Nanoparticles Improves the Thawing of Cryopreserved Biomaterials October 23rd, 2014

Sopping up proteins with thermosponges: Researchers develop novel nanoparticle platform that proves effective in delivering protein-based drugs October 22nd, 2014

Discoveries

QuantumWise guides the semiconductor industry towards the atomic scale October 24th, 2014

Iranian, Malaysian Scientists Study Nanophotocatalysts for Water Purification October 23rd, 2014

Nanoparticle technology triples the production of biogas October 23rd, 2014

Strengthening thin-film bonds with ultrafast data collection October 23rd, 2014

Announcements

Iran to Hold 3rd Int'l Engineering Materials, Metallurgy Conference October 25th, 2014

Haydale Secures Exclusive Development and Supply Agreement with Tantec A/S: New reactors to be built and commissioned by Tantec A/S represent another step forward towards the commercialisation of graphene October 24th, 2014

QuantumWise guides the semiconductor industry towards the atomic scale October 24th, 2014

Strengthening thin-film bonds with ultrafast data collection 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