Nanotechnology Now





Heifer International

Wikipedia Affiliate Button


DHgate

Home > Press > Multifunctional nanoparticle enables new type of biological imaging

The 30-nanometer particle combines a magnetic core with a thin gold shell, analogous to an eggshell, that surrounds but does not touch the core. Credit: Xiaohu Gao, University of Washington
The 30-nanometer particle combines a magnetic core with a thin gold shell, analogous to an eggshell, that surrounds but does not touch the core. Credit: Xiaohu Gao, University of Washington

Abstract:
Spotting a single cancerous cell that has broken free from a tumor and is traveling through the bloodstream to colonize a new organ might seem like finding a needle in a haystack. But a new imaging technique from the University of Washington is a first step toward making this possible.

By Hannah Hickey

Multifunctional nanoparticle enables new type of biological imaging

Seattle, WA | Posted on July 28th, 2010

UW researchers have developed a multifunctional nanoparticle that eliminates the background noise, enabling a more precise form of medical imaging -- essentially erasing the haystack, so the needle shines through. A successful demonstration with photoacoustic imaging was reported today (July 27) in the journal Nature Communications.

Nanoparticles are promising contrast agents for ultrasensitive medical imaging. But in all techniques that do not use radioactive tracers, the surrounding tissues tend to overwhelm weak signals, preventing researchers from detecting just one or a few cells.

"Although the tissues are not nearly as effective at generating a signal as the contrast agent, the quantity of the tissue is much greater than the quantity of the contrast agent and so the background signal is very high," said lead author Xiaohu Gao, a UW assistant professor of bioengineering.

The newly presented nanoparticle solves this problem by for the first time combining two properties to create an image that is different from what any existing technique could have produced.

The new particle combines magnetic properties and photoacoustic imaging to erase the background noise. Researchers used a pulsing magnetic field to shake the nanoparticles by their magnetic cores. Then they took a photoacoustic image and used image processing techniques to remove everything except the vibrating pixels.

Gao compares the new technique to "Tourist Remover" photo editing software that allows a photographer to delete other people by combining several photos of the same scene and keeping only the parts of the image that aren't moving.

"We are using a very similar strategy," Gao said. "Instead of keeping the stationary parts, we only keep the moving part.

"We use an external magnetic field to shake the particles," he explained. "Then there's only one type of particle that will shake at the frequency of our magnetic field, which is our own particle."

Experiments with synthetic tissue showed the technique can almost completely suppress a strong background signal. Future work will try to duplicate the results in lab animals, Gao said.

The 30-nanometer particle consists of an iron-oxide magnetic core with a thin gold shell that surrounds but does not touch the center. The gold shell is used to absorb infrared light, and could also be used for optical imaging, delivering heat therapy, or attaching a biomolecule that would grab on to specific cells.

Earlier work by Gao's group combined functions in a single nanoparticle, something that is difficult because of the small size.

"In nanoparticles, one plus one is often less than two," Gao said. "Our previous work showed that one plus one can be equal to two. This paper shows that one plus one is, finally, greater than two."

The first biological imaging, in the 1950s, was used to identify anatomy inside the body, detecting tumors or fetuses. The second generation has been used to monitor function -- fMRI, or functional magnetic resonance imaging, for example, detects oxygen use in the brain to produce a picture of brain activity. The next generation of imaging will be molecular imaging, said co-author Matthew O'Donnell, a UW professor of bioengineering and engineering dean.

This will mean that medical assays and cell counts can be done inside the body. In other words, instead of taking a biopsy and inspecting tissue under a microscope, imaging could detect specific proteins or abnormal activity at the source.

But making this happen means improving the confidence limits of the imaging.

"Today, we can use biomarkers to see where there's a large collection of diseased cells," O'Donnell said. "This new technique could get you down to a very precise level, potentially of a single cell."

Researchers tested the method for photoacoustic imaging, a low-cost method now being developed that is sensitive to slight variations in tissues' properties and can penetrate several centimeters in soft tissue. It works by using a pulse of laser light to heat a cell very slightly. This heat causes the cell to vibrate and produce ultrasound waves that travel through the tissue to the body's surface. The new technique should also apply to other types of imaging, the authors said.

Co-authors are UW postdoctoral researchers Yongdong Jin and Sheng-Wen Huang and University of Michigan doctoral student Congxian Jia.

Research was funded by the National Institutes of Health, the National Science Foundation and the UW Department of Bioengineering.

####

For more information, please click here

Contacts:
Xiaohu Gao
206-543-6562


Matthew O'Donnell
206-543-1829


Hannah Hickey

Copyright © University of Washington

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

Nanospiked bacteria are the brightest hard X-ray emitters July 2nd, 2015

Engineering the world’s smallest nanocrystal July 2nd, 2015

Producing spin-entangled electrons July 2nd, 2015

NIST Group Maps Distribution of Carbon Nanotubes in Composite Materials July 2nd, 2015

Govt.-Legislation/Regulation/Funding/Policy

New technology using silver may hold key to electronics advances July 2nd, 2015

NIST Group Maps Distribution of Carbon Nanotubes in Composite Materials July 2nd, 2015

Influential Interfaces Lead to Advances in Organic Spintronics July 1st, 2015

NIST ‘How-To’ Website Documents Procedures for Nano-EHS Research and Testing July 1st, 2015

Possible Futures

Harris & Harris Group Portfolio Company D-Wave Systems Announces 1,000 Qubit Processor and is Discussed in the Economist June 23rd, 2015

Global Nanoclays Market Analysis, Size, Growth, Trends And Segment Forecasts, 2015 To 2022: Grand View Research, Inc June 15th, 2015

Healthcare Nanotechnology (Nanomedicine) Market Size To 2020 June 5th, 2015

Environmental Issues to Hamper Growth of Global Nanocomposites Market June 4th, 2015

Academic/Education

Oxford Instruments’ TritonXL Cryofree dilution refrigerator selected for the Oxford NQIT Quantum Technology Hub project June 30th, 2015

Rice University boots up powerful microscopes: New electron microscopes will capture images at subnanometer resolution June 29th, 2015

Six top Catalan research centres constitute ‘The Barcelona Institute of Science and Technology’ to pursue a joint scientific endeavour June 27th, 2015

Lancaster University revolutionary quantum technology research receives funding boost June 22nd, 2015

Nanomedicine

Iranian Scientists Find Simple, Economic Method to Synthesize Antibacterial Nanoparticles July 2nd, 2015

Leti Announces Launch of First European Nanomedicine Characterisation Laboratory: Project Combines Expertise of 9 Partners in 8 Countries to Foster Nanomedicine Innovation and Facilitate Regulatory Approval July 1st, 2015

Carnegie Mellon chemists characterize 3-D macroporous hydrogels: Methods will allow researchers to develop new 'smart' materials June 30th, 2015

Chitosan coated, chemotherapy packed nanoparticles may target cancer stem cells June 30th, 2015

Announcements

Nanospiked bacteria are the brightest hard X-ray emitters July 2nd, 2015

Engineering the world’s smallest nanocrystal July 2nd, 2015

Producing spin-entangled electrons July 2nd, 2015

NIST Group Maps Distribution of Carbon Nanotubes in Composite Materials July 2nd, 2015

Tools

NIST ‘How-To’ Website Documents Procedures for Nano-EHS Research and Testing July 1st, 2015

Ultra-stable JILA microscopy technique tracks tiny objects for hours July 1st, 2015

Bruker Introduces Second-Generation Inspire Nanochemical Imaging Solution: Featuring Unique PeakForce IR and IR EasyAlign Technology July 1st, 2015

Carnegie Mellon chemists characterize 3-D macroporous hydrogels: Methods will allow researchers to develop new 'smart' materials June 30th, 2015

Research partnerships

Producing spin-entangled electrons July 2nd, 2015

Harris & Harris Group Portfolio Company, AgBiome, Announces Partnership to Accelerate the Discovery of Next Generation Insect-Resistant Crops July 1st, 2015

Leti Announces Launch of First European Nanomedicine Characterisation Laboratory: Project Combines Expertise of 9 Partners in 8 Countries to Foster Nanomedicine Innovation and Facilitate Regulatory Approval July 1st, 2015

Carnegie Mellon chemists characterize 3-D macroporous hydrogels: Methods will allow researchers to develop new 'smart' materials June 30th, 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