Nanotechnology Now







Heifer International

Wikipedia Affiliate Button


DHgate

Home > Press > UConn chemists find secret to increasing luminescence efficiency of carbon nanotubes

Abstract:
Breakthrough procedure has potential applications in medical imaging, homeland security, biological sensors

UConn chemists find secret to increasing luminescence efficiency of carbon nanotubes

Storrs, CT | Posted on March 6th, 2009

Chemists at the University of Connecticut have found a way to greatly increase the luminescence efficiency of single-walled carbon nanotubes, a discovery that could have significant applications in medical imaging and other areas.

Increasing the luminescence efficiency of carbon nanotubes may someday make it possible for doctors to inject patients with microscopic nanotubes to detect tumors, arterial blockages and other internal problems. Rather than relying on potentially harmful x-rays or the use of radioactive dyes, physicians could simply scan patients with an infrared light that would capture a very sharp resolution of the luminescence of the nanotubes in problem areas.

UConn's process of increasing the luminescence efficiency of single-walled carbon nanotubes will be featured in Science magazine on Friday, March 6, 2009. The research was performed in the Nanomaterials Optoelectronics Laboratory at the Institute of Materials Science at the University of Connecticut, in Storrs, CT. A patent for the process is pending.

University of Connecticut Chemist Fotios Papadimitrakopoulos describes the discovery as a major breakthrough and one of the most significant discoveries in his 10 years of working with single-walled carbon nanotubes. Assisting Papadimitrakopoulos with the research were Polymer Program graduate student Sang-Yong Ju (now a researcher at Cornell University) and William P. Kopcha, a former Chemistry undergraduate assistant in the College of Liberal Arts and Sciences who is now a first-year graduate student at UConn.

Although carbon is used in many diverse applications, scientists have long been stymied by the element's limited ability to emit light. The best scientists have been able to do with solution-suspended carbon nanotubes was to raise their luminescence efficiency to about one-half of one percent, which is extremely low compared to other materials, such as quantum dots and quantum rods.

By tightly wrapping a chemical 'sleeve' around a single-walled carbon nanotube, Papadimitrakopoulos and his research team were able to reduce exterior defects caused by chemically absorbed oxygen molecules.

This process can best be explained by imagining sliding a small tube into a slightly larger diameter tube, Papadimitrakopoulos says. In order for this to happen, all deposits or protrusions on the smaller tube have to be removed before the tube is allowed to slip into the slightly larger diameter tube. What is most fascinating with carbon nanotubes however, Papadimitrakopoulos says, is the fact that in this case the larger tube is not as rigid as the first tube (i.e. carbon nanotube) but is rather formed by a chemical "sleeve" comprised of a synthetic derivative of flavin (an analog of vitamin B2) that adsorbs and self organizes onto a conformal tube.
Papadimitrakopoulos claims that this process of self-assembly is unique in that it not only forms a new structure but also actively "cleans" the surface of the underlying nanotube. It is that active cleaning of the nanotube surface that allows the nanotube to achieve luminescence efficiency to as high as 20 percent.

NOTE: To see a QuickTime animation of how a single-walled carbon nanotube is wrapped with the synthetic flavin derivative to increase its luminescence go to: www.ims.uconn.edu/~papadim/research.htm

"The nanotube is the smallest tube on earth and we have found a sleeve to put over it," Papadimitrakopoulos says. "This is the first time that a nanotube was found to emit with as much as 20 percent luminescence efficiency."

Papadimitrakopoulos has been working closely with the UConn Center for Science and Technology Commercialization (CSTC) in transferring his advances in research into the realm of patents, licenses and corporate partnerships. The CSTC was created several years ago as a way to help expand Connecticut's innovation-based economy and to help create new businesses and jobs around new ideas.

This is the second major nanotube discovery at UConn by Papadimitrakopoulos in the past two years. Last year, Papadimitrakopoulos and Sang-Young Ju, along with other UConn researchers, patented a way to isolate certain carbon nanotubes from others by seamlessly wrapping a form of vitamin B2 around the nanotubes. It was out of that research that Papadimitrakopoulos and Sang-Yong Ju began wrapping nanotubes with helical assemblies and probing their luminescence properties.

The more luminescent the nanotube, the brighter it appears under infrared irradiation or by electrical excitation (such as that provided by a light-emitting diode or LED). A number of important applications may be possible as a result of this research, Papadimitrakopoulos says. Carbon nanotube emissions are not only extremely sharp, but they also appear in a spectral region where minimal absorption or scattering takes place by soft tissue. Moreover, carbon nanotubes display superb photo bleaching stability and are ideally suited for near-infrared emitters, making them appropriate for applications in medicine and homeland security as bio-reporting agents and nano-sized beacons. Carbon nanotube luminescence also has important applications in nano-scaled LEDs and photo detectors, which can readily integrate with silicon-based technology. This provides an enormous repertoire for nanotube use in advanced fiber optics components, infrared light modulators, and biological sensors, where multiple applications are possible due to the nanotube's flavin-based (vitamin B2) helical wrapping.

A complete copy of the research article that will appear in Science magazine on Friday, March 6, will be available after 2 p.m. on Thursday, March 5 at: www.sciencemag.org/sciencexpress/recent.dtl

More information about the University of Connecticut's Nanomaterials Optoelectronics Laboratory can be found at: chemistry.uconn.edu/papadim/index.htm

####

For more information, please click here

Contacts:
Colin Poitras

860-486-4656

Additional Contact Information:
Fotios Papadimitrakopoulos
Professor of Chemistry
Associate Director
Institute of Materials Science
University of Connecticut
Tel: (860)-486-3447
Fax: (860)-486-4745

Copyright © University of Connecticut

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

Nanoscale worms provide new route to nano-necklace structures March 29th, 2015

Solving molybdenum disulfide's 'thin' problem: Research team increases material's light emission by twelve times March 29th, 2015

A first glimpse inside a macroscopic quantum state March 28th, 2015

DFG to Establish One Clinical Research Unit and Five Research Units: New Projects to Investigate Complications in Pregnancy, Particle Physics, Nanoparticles, Implants and Transport Planning / Approximately 13 Million Euros in Funding for an Initial Three-Year Period March 28th, 2015

State-of-the-art online system unveiled to pinpoint metrology software accuracy March 27th, 2015

Chemistry

Chemists make new silicon-based nanomaterials March 27th, 2015

Imaging

FEI Technology Award of the German Neuroscience Society Goes to Benjamin Judkewitz of the University of Berlin: Bi-annual award honors excellence in brain research during the German Neuroscience Society’s Annual Meeting, held 18-21 March 2015 March 26th, 2015

Square ice filling for a graphene sandwich March 26th, 2015

Renishaw reports on the use of Raman spectroscopy at CNRS Orléans to study materials under extreme conditions March 25th, 2015

Nanorobotic agents open the blood-brain barrier, offering hope for new brain treatments March 25th, 2015

Nanotubes/Buckyballs

Carbon nanotube fibers make superior links to brain: Rice University invention provides two-way communication with neurons March 25th, 2015

Iranian Scientists Eliminate Expensive Materials from Diabetes Diagnosis Sensors March 25th, 2015

Effect of Carbon Nanotubes on Properties of Cement Composites Studied in Iran March 23rd, 2015

First proof of isolated attosecond pulse generation at the carbon K-edge March 20th, 2015

Sensors

UW scientists build a nanolaser using a single atomic sheet March 24th, 2015

Iranian Researchers Present Model to Determine Dynamic Behavior of Nanostructures March 24th, 2015

Nanodevice Invented in Iran to Detect Hydrogen Sulfide in Oil, Gas Industry March 20th, 2015

LamdaGen Corporation Launches Taiwan Diagnostic Subsidiary March 19th, 2015

Discoveries

Nanoscale worms provide new route to nano-necklace structures March 29th, 2015

Solving molybdenum disulfide's 'thin' problem: Research team increases material's light emission by twelve times March 29th, 2015

A first glimpse inside a macroscopic quantum state March 28th, 2015

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

Announcements

Nanoscale worms provide new route to nano-necklace structures March 29th, 2015

Solving molybdenum disulfide's 'thin' problem: Research team increases material's light emission by twelve times March 29th, 2015

A first glimpse inside a macroscopic quantum state March 28th, 2015

DFG to Establish One Clinical Research Unit and Five Research Units: New Projects to Investigate Complications in Pregnancy, Particle Physics, Nanoparticles, Implants and Transport Planning / Approximately 13 Million Euros in Funding for an Initial Three-Year Period March 28th, 2015

Homeland Security

The Universitat Politècnica de València is coordinating a European project to develop a device for the quick and early diagnosis of cancer March 7th, 2015

Detecting chemical weapons with a color-changing film January 28th, 2015

Detection of Heavy Metals in Samples with Naked Eye January 26th, 2015

Detecting gases wirelessly and cheaply: New sensor can transmit information on hazardous chemicals or food spoilage to a smartphone December 8th, 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 1999-2015 7th Wave, Inc. All Rights Reserved PRIVACY POLICY :: CONTACT US :: STATS :: SITE MAP :: ADVERTISE