Nanotechnology Now

Our NanoNews Digest Sponsors

Heifer International

Wikipedia Affiliate Button

Home > Press > 'Label-free' imaging tool tracks nanotubes in cells, blood for biomedical research

Researchers have demonstrated a new imaging tool for tracking structures called single-wall carbon nanotubes in living cells and the bloodstream, work that could aid efforts to perfect their use in laboratory or medical applications. Here, the imaging system detects both metallic and semiconducting nanotubes, false-colored in red and green, in live hamster cells. (Weldon School of Biomedical Engineering, Purdue University)
Researchers have demonstrated a new imaging tool for tracking structures called single-wall carbon nanotubes in living cells and the bloodstream, work that could aid efforts to perfect their use in laboratory or medical applications. Here, the imaging system detects both metallic and semiconducting nanotubes, false-colored in red and green, in live hamster cells.

(Weldon School of Biomedical Engineering, Purdue University)

Abstract:
Label-Free Imaging of Semiconducting and Metallic Carbon Nanotubes in Cells and Mice Using Transient Absorption Microscopy

Ling Tong1, Yuxiang Liu2, Bridget D. Dolash3, Yookyung Jung4, Mikhail N. Slipchenko2, Donald E. Bergstrom3,5 and Ji-Xin Cheng1,2,5*

1Department of Chemistry; 2Weldon School of Biomedical Engineering, 3Department of Medical Chemistry and Molecular Pharmacology; 4Department of Physics,5 Birck Nanotechnology Center, Purdue University

As interest in the potential biomedical applications of carbon nanotubes increases, there is a need for methods that can image nanotubes in live cells, tissues and animals. Although techniques such as Raman, photoacoustic and near-infrared photoluminescence imaging have been used to visualize nanotubes in biological environments, these techniques are limited because nanotubes provide only weak photoluminescence and low Raman scattering and it remains difficult to image both semiconducting and metallic nanotubes at the same time. Here, we show that transient absorption microscopy offers a label-free method to image both semiconducting and metallic single-walled carbon nanotubes in vitro and in vivo, in real time, with submicrometre resolution. By using appropriate near-infrared excitation wavelengths, we detect strong transient absorption signals with opposite phases from semiconducting and metallic nanotubes. Our method separates background signals generated by red blood cells and this allows us to follow the movement of both types of nanotubes inside cells and in the blood circulation and organs of mice without any significant damaging effects.

'Label-free' imaging tool tracks nanotubes in cells, blood for biomedical research

West Lafayette, IN | Posted on December 5th, 2011

Researchers have demonstrated a new imaging tool for tracking structures called carbon nanotubes in living cells and the bloodstream, which could aid efforts to perfect their use in biomedical research and clinical medicine.

The structures have potential applications in drug delivery to treat diseases and imaging for cancer research. Two types of nanotubes are created in the manufacturing process, metallic and semiconducting. Until now, however, there has been no technique to see both types in living cells and the bloodstream, said Ji-Xin Cheng, an associate professor of biomedical engineering and chemistry at Purdue University.

The imaging technique, called transient absorption, uses a pulsing near-infrared laser to deposit energy into the nanotubes, which then are probed by a second near-infrared laser.

The researchers have overcome key obstacles in using the imaging technology, detecting and monitoring the nanotubes in live cells and laboratory mice, Cheng said.

"Because we can do this at high speed, we can see what's happening in real time as the nanotubes are circulating in the bloodstream," he said.

Findings are detailed in a research paper posted online Sunday (Dec. 4) in the journal Nature Nanotechnology.

The imaging technique is "label free," meaning it does not require that the nanotubes be marked with dyes, making it potentially practical for research and medicine, Cheng said.

"It's a fundamental tool for research that will provide information for the scientific community to learn how to perfect the use of nanotubes for biomedical and clinical applications," he said.

The conventional imaging method uses luminescence, which is limited because it detects the semiconducting nanotubes but not the metallic ones.

The nanotubes have a diameter of about 1 nanometer, or roughly the length of 10 hydrogen atoms strung together, making them far too small to be seen with a conventional light microscope. One challenge in using the transient absorption imaging system for living cells was to eliminate the interference caused by the background glow of red blood cells, which is brighter than the nanotubes.

The researchers solved this problem by separating the signals from red blood cells and nanotubes in two separate "channels." Light from the red blood cells is slightly delayed compared to light emitted by the nanotubes. The two types of signals are "phase separated" by restricting them to different channels based on this delay.

Researchers used the technique to see nanotubes circulating in the blood vessels of mice earlobes.

"This is important for drug delivery because you want to know how long nanotubes remain in blood vessels after they are injected," Cheng said. "So you need to visualize them in real time circulating in the bloodstream."

The structures, called single-wall carbon nanotubes, are formed by rolling up a one-atom-thick layer of graphite called graphene. The nanotubes are inherently hydrophobic, so some of the nanotubes used in the study were coated with DNA to make them water-soluble, which is required for them to be transported in the bloodstream and into cells.

The researchers also have taken images of nanotubes in the liver and other organs to study their distribution in mice, and they are using the imaging technique to study other nanomaterials such as graphene.

The paper was written by doctoral student Ling Tong; postdoctoral research associate Yuxiang Liu; doctoral students Bridget D. Dolash and Yookyung Jung; biomedical engineering research scientist Mikhail N. Slipchenko; Donald E. Bergstrom, the Walther Professor of Medicinal Chemistry; and Cheng.

The research is funded by the National Science Foundation.

####

For more information, please click here

Contacts:
Writer:
Emil Venere
765-494-4709


Source:
Ji-Xin Cheng
765-494-4335

Copyright © Purdue 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 Links

Purdue Weldon School of Biomedical Engineering

Purdue Department of Chemistry

Chen Yang

Related News Press

News and information

A nanoscale wireless communication system via plasmonic antennas: Greater control affords 'in-plane' transmission of waves at or near visible light August 27th, 2016

Forces of nature: Interview with microscopy innovators Gerd Binnig and Christoph Gerber August 26th, 2016

A promising route to the scalable production of highly crystalline graphene films August 26th, 2016

Graphene under pressure August 26th, 2016

Imaging

Forces of nature: Interview with microscopy innovators Gerd Binnig and Christoph Gerber August 26th, 2016

Graphene/ Graphite

A promising route to the scalable production of highly crystalline graphene films August 26th, 2016

Graphene under pressure August 26th, 2016

Govt.-Legislation/Regulation/Funding/Policy

Analog DNA circuit does math in a test tube: DNA computers could one day be programmed to diagnose and treat disease August 25th, 2016

New approach to determining how atoms are arranged in materials August 25th, 2016

Johns Hopkins scientists track metabolic pathways to find drug combination for pancreatic cancer August 25th, 2016

New electrical energy storage material shows its power: Nanomaterial combines attributes of both batteries and supercapacitors August 25th, 2016

Chip Technology

A nanoscale wireless communication system via plasmonic antennas: Greater control affords 'in-plane' transmission of waves at or near visible light August 27th, 2016

A promising route to the scalable production of highly crystalline graphene films August 26th, 2016

Analog DNA circuit does math in a test tube: DNA computers could one day be programmed to diagnose and treat disease August 25th, 2016

Silicon nanoparticles trained to juggle light: Research findings prove the capabilities of silicon nanoparticles for flexible data processing in optical communication systems August 25th, 2016

Nanotubes/Buckyballs/Fullerenes

Tunneling nanotubes between neurons enable the spread of Parkinson's disease via lysosomes August 24th, 2016

McMaster researchers resolve a problem that has been holding back a technological revolution August 18th, 2016

'Second skin' protects soldiers from biological and chemical agents August 5th, 2016

Carbon nanotube 'stitches' make stronger, lighter composites: Method to reinforce these materials could help make airplane frames lighter, more damage-resistant August 4th, 2016

Nanomedicine

Nanofiber scaffolds demonstrate new features in the behavior of stem and cancer cells August 25th, 2016

Johns Hopkins scientists track metabolic pathways to find drug combination for pancreatic cancer August 25th, 2016

50 years after the release of the film 'Fantastic Voyage,' science upstages fiction: Science upstages fiction with nanorobotic agents designed to travel in the human body to treat cancer August 25th, 2016

Tunneling nanotubes between neurons enable the spread of Parkinson's disease via lysosomes August 24th, 2016

Discoveries

A promising route to the scalable production of highly crystalline graphene films August 26th, 2016

Graphene under pressure August 26th, 2016

Nanofur for oil spill cleanup: Materials researchers learn from aquatic ferns: Hairy plant leaves are highly oil-absorbing / publication in bioinspiration & biomimetics / video on absorption capacity August 25th, 2016

Unraveling the crystal structure of a -70 Celsius superconductor, a world first: Significant advancement in the realization of room-temperature superconductors August 25th, 2016

Announcements

A nanoscale wireless communication system via plasmonic antennas: Greater control affords 'in-plane' transmission of waves at or near visible light August 27th, 2016

Forces of nature: Interview with microscopy innovators Gerd Binnig and Christoph Gerber August 26th, 2016

A promising route to the scalable production of highly crystalline graphene films August 26th, 2016

Graphene under pressure August 26th, 2016

Tools

Nanofiber scaffolds demonstrate new features in the behavior of stem and cancer cells August 25th, 2016

50 years after the release of the film 'Fantastic Voyage,' science upstages fiction: Science upstages fiction with nanorobotic agents designed to travel in the human body to treat cancer August 25th, 2016

University of Puerto Rico and NASA back in the news XEI reports August 23rd, 2016

Spider silk: Mother Nature's bio-superlens August 22nd, 2016

Safety-Nanoparticles/Risk management

UK NANOSAFETY GROUP publishes 2nd Edition of guidance to support safe working with nanomaterials May 30th, 2016

PETA science group publishes a review on pulmonary effects of nanomaterials: Archives of Toxicology publishes a review of scientific studies on fibrotic potential of nanomaterials May 26th, 2016

Common nanoparticle has subtle effects on oxidative stress genes May 11th, 2016

Non-animal approach to predict impact of nanomaterials on human lung published Archives of Toxicology publishes workshop recommendations May 2nd, 2016

Photonics/Optics/Lasers

Silicon nanoparticles trained to juggle light: Research findings prove the capabilities of silicon nanoparticles for flexible data processing in optical communication systems August 25th, 2016

AIM Photonics Announces Release of Process Design Kit (PDK) for Integrated Silicon Photonics Design August 25th, 2016

New theory could lead to new generation of energy friendly optoelectronics: Researchers at Queen's University Belfast and ETH Zurich, Switzerland, have created a new theoretical framework which could help physicists and device engineers design better optoelectronics August 23rd, 2016

Hexagonal boron nitride semiconductors enable cost-effective detection of neutron signals: Texas Tech University researchers demonstrate hexagonal boron nitride semiconductors as a cost-effective alternative for inspecting overseas cargo containers entering US ports August 17th, 2016

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







Car Brands
Buy website traffic