Nanotechnology Now

Our NanoNews Digest Sponsors
Heifer International



Home > Press > Twinkling Nanostars Improve Optical Imaging of Tumors

Abstract:
Researchers at Purdue University have created magnetically responsive gold nanostars that may offer a new approach to biomedical imaging. The nanostars gyrate when exposed to a rotating magnetic field and can scatter light to produce a pulsating or "twinkling" effect. This twinkling allows them to stand out more clearly from noisy backgrounds such as those found in biological tissue. Alexander Wei, Ph.D., and Kenneth Ritchie, Ph.D., M.Sc., led the team that created the new gyromagnetic imaging method. The work appears in a paper published in the Journal of the American Chemical Society.

Twinkling Nanostars Improve Optical Imaging of Tumors

Bethesda , MD | Posted on September 24th, 2009

"This is a very different approach to enhancing contrast in optical imaging," said Dr. Wei. "Brighter isn't necessarily better for imaging; the real issue is background noise, and you can't always overcome this simply by creating brighter particles. With gyromagnetic imaging, we can zero in on the nanostars by increasing signal strength while cutting down on background noise."

The gold nanostars are about 100 nanometers from tip to tip and contain an iron oxide core that causes them to spin when exposed to a rotating magnet. The arms of the nanostar are designed to respond to a light source and reflect light to a camera when properly aligned. This gives nanostars the appearance of twinkling at rates that can be precisely controlled by the speed of the rotating magnetic field. The unique signature of the twinkling nanostars enables them to be picked out easily from a field of stationary particles, some of which can be brighter than the nanostars.

Any signal that does not have the frequency corresponding to the rotating magnetic field can be suppressed in the images, eliminating background noise, Dr. Ritchie said. "It was surprising how well this method enhanced the imaging. It can improve the contrast of the particles to the background noise by more than 20 decibels and can clearly reveal a gyrating nanostar, whereas with existing direct imaging methods, in many cases you wouldn't be able to definitively find a particle."

To perform gyromagnetic imaging, the team placed a sample of cells containing nanostars under a standard microscope equipped with a white light source and a rotating magnet. They then sent light through a polarizing beam splitter and into the sample. The light then reflected back through the beam splitter and to the camera. The camera collected images at 120 frames per second, capturing the signal from the nanostars as they spun at approximately 5 revolutions per second.

The setup is simple and practical for general laboratory use, Dr. Ritchie said. "To translate a new imaging technique into something practical for broad use, it needs to be done without specialized equipment," he noted. "Many other imaging techniques require expensive equipment or lasers, but this method can be done with a halogen lamp and a $10,000 camera."

After initial data are collected, mathematical operations such as Fourier transforms can be applied to obtain frequency information from the pulsating light signals, allowing the twinkling nanostars to be easily picked out. Biocompatibility tests failed to find any toxicities associated with the nanostars.

####

About National Cancer Institute
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 today’s 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 © National Cancer Institute

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 - “Gyromagnetic imaging: dynamic optical contrast using gold nanostars with magnetic cores.”

Related News Press

News and information

Virginia Tech physicists propose path to faster, more flexible robots: Virginia Tech physicists revealed a microscopic phenomenon that could greatly improve the performance of soft devices, such as agile flexible robots or microscopic capsules for drug delivery May 17th, 2024

Gene therapy relieves back pain, repairs damaged disc in mice: Study suggests nanocarriers loaded with DNA could replace opioids May 17th, 2024

Shedding light on perovskite hydrides using a new deposition technique: Researchers develop a methodology to grow single-crystal perovskite hydrides, enabling accurate hydride conductivity measurements May 17th, 2024

Oscillating paramagnetic Meissner effect and Berezinskii-Kosterlitz-Thouless transition in cuprate superconductor May 17th, 2024

Imaging

Nanoscale CL thermometry with lanthanide-doped heavy-metal oxide in TEM March 8th, 2024

First direct imaging of small noble gas clusters at room temperature: Novel opportunities in quantum technology and condensed matter physics opened by noble gas atoms confined between graphene layers January 12th, 2024

The USTC realizes In situ electron paramagnetic resonance spectroscopy using single nanodiamond sensors November 3rd, 2023

Observation of left and right at nanoscale with optical force October 6th, 2023

Govt.-Legislation/Regulation/Funding/Policy

International research team uses wavefunction matching to solve quantum many-body problems: New approach makes calculations with realistic interactions possible May 17th, 2024

Aston University researcher receives £1 million grant to revolutionize miniature optical devices May 17th, 2024

NRL charters Navy’s quantum inertial navigation path to reduce drift April 5th, 2024

Discovery points path to flash-like memory for storing qubits: Rice find could hasten development of nonvolatile quantum memory April 5th, 2024

Nanomedicine

Virginia Tech physicists propose path to faster, more flexible robots: Virginia Tech physicists revealed a microscopic phenomenon that could greatly improve the performance of soft devices, such as agile flexible robots or microscopic capsules for drug delivery May 17th, 2024

Diamond glitter: A play of colors with artificial DNA crystals May 17th, 2024

Advances in priming B cell immunity against HIV pave the way to future HIV vaccines, shows quartet of new studies May 17th, 2024

New micromaterial releases nanoparticles that selectively destroy cancer cells April 5th, 2024

Discoveries

Virginia Tech physicists propose path to faster, more flexible robots: Virginia Tech physicists revealed a microscopic phenomenon that could greatly improve the performance of soft devices, such as agile flexible robots or microscopic capsules for drug delivery May 17th, 2024

Diamond glitter: A play of colors with artificial DNA crystals May 17th, 2024

Finding quantum order in chaos May 17th, 2024

Advances in priming B cell immunity against HIV pave the way to future HIV vaccines, shows quartet of new studies May 17th, 2024

Announcements

Virginia Tech physicists propose path to faster, more flexible robots: Virginia Tech physicists revealed a microscopic phenomenon that could greatly improve the performance of soft devices, such as agile flexible robots or microscopic capsules for drug delivery May 17th, 2024

Diamond glitter: A play of colors with artificial DNA crystals May 17th, 2024

Finding quantum order in chaos May 17th, 2024

Oscillating paramagnetic Meissner effect and Berezinskii-Kosterlitz-Thouless transition in cuprate superconductor May 17th, 2024

NanoNews-Digest
The latest news from around the world, FREE




  Premium Products
NanoNews-Custom
Only the news you want to read!
 Learn More
NanoStrategies
Full-service, expert consulting
 Learn More











ASP
Nanotechnology Now Featured Books




NNN

The Hunger Project