Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Using nanomagnets to enhance medical imaging

06.02.2007
Nanoscale magnets in the form of iron-containing molecules might be used to improve the contrast between healthy and diseased tissue in magnetic resonance imaging (MRI)—as long as the concentration of nanomagnets is carefully managed—according to a new report* by researchers at the National Institute of Standards and Technology (NIST) and collaborators. Molecular nanomagnets are a new class of MRI contrast agents that may offer significant advantages, such as versatility in design, over the compounds used today.

Contrast agents are used to highlight different tissues in the body or to help distinguish between healthy and diseased tissue. NIST is working with two universities and a hospital to design, produce and test nanomolecules that might make MRI imaging more powerful and easier to perform.

The new paper resolves a debate in the literature by showing that iron-containing magnets just two nanometers wide, dissolved in water, do provide reasonable contrast in non-clinical MRI images—as long as the nanomagnet concentration is below a certain threshold. (A nanometer is one billionth of a meter.) Previous studies by other research groups had reached conflicting conclusions on the utility of molecular nanomagnets for MRI, but without accounting for concentration. NIST scientists, making novel magnetic measurements, were able to monitor the molecules' decomposition and magnetic properties as the composition was varied.

The injectable dyes currently used as MRI contrast agents are of two types. Magnetic ions, which alter the nuclear properties of hydrogen in water, offer the advantage of consistent identical design but provide low contrast. The second category encompasses particles of thousands of atoms or crystals, which alter local magnetic fields; they provide contrast variation in a larger region but have irregular designs and magnetic properties that are difficult to control. By comparison, molecular nanomagnets can be designed to have consistent properties and high contrast. In addition, they might be modified to act as "smart" materials whose contrast could be turned on only when bonded to a target molecule or cell. Toxicity is not believed to be an issue, because iron is naturally found in the body and other studies have found that these materials are non-toxic at the concentrations used in MRI.

NIST works with Florida State University to make single-molecule magnets less than five nanometers (nm) in diameter, and works with the University of Colorado at Boulder to make nanocrystals in the 10-50 nm range. The agency is pioneering methods for manipulating and measuring the magnetic properties of these compounds and is developing instrumentation for understanding how contrast agents work and how to control contrast properties. Researchers correlate the measured properties to the observed MRI response under non-clinical conditions using imagers at The Children's Hospital in Denver. The information gained is fed back into recipes for making even better nanomagnets. The work described in the new paper was supported in part by the National Science Foundation.

Laura Ost | EurekAlert!
Further information:
http://www.nist.gov

More articles from Medical Engineering:

nachricht New imaging technique able to watch molecular dynamics of neurodegenerative diseases
14.07.2017 | The Optical Society

nachricht Quick test finds signs of sepsis in a single drop of blood
03.07.2017 | University of Illinois at Urbana-Champaign

All articles from Medical Engineering >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Physicists Design Ultrafocused Pulses

Physicists working with researcher Oriol Romero-Isart devised a new simple scheme to theoretically generate arbitrarily short and focused electromagnetic fields. This new tool could be used for precise sensing and in microscopy.

Microwaves, heat radiation, light and X-radiation are examples for electromagnetic waves. Many applications require to focus the electromagnetic fields to...

Im Focus: Carbon Nanotubes Turn Electrical Current into Light-emitting Quasi-particles

Strong light-matter coupling in these semiconducting tubes may hold the key to electrically pumped lasers

Light-matter quasi-particles can be generated electrically in semiconducting carbon nanotubes. Material scientists and physicists from Heidelberg University...

Im Focus: Flexible proximity sensor creates smart surfaces

Fraunhofer IPA has developed a proximity sensor made from silicone and carbon nanotubes (CNT) which detects objects and determines their position. The materials and printing process used mean that the sensor is extremely flexible, economical and can be used for large surfaces. Industry and research partners can use and further develop this innovation straight away.

At first glance, the proximity sensor appears to be nothing special: a thin, elastic layer of silicone onto which black square surfaces are printed, but these...

Im Focus: 3-D scanning with water

3-D shape acquisition using water displacement as the shape sensor for the reconstruction of complex objects

A global team of computer scientists and engineers have developed an innovative technique that more completely reconstructs challenging 3D objects. An ancient...

Im Focus: Manipulating Electron Spins Without Loss of Information

Physicists have developed a new technique that uses electrical voltages to control the electron spin on a chip. The newly-developed method provides protection from spin decay, meaning that the contained information can be maintained and transmitted over comparatively large distances, as has been demonstrated by a team from the University of Basel’s Department of Physics and the Swiss Nanoscience Institute. The results have been published in Physical Review X.

For several years, researchers have been trying to use the spin of an electron to store and transmit information. The spin of each electron is always coupled...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Clash of Realities 2017: Registration now open. International Conference at TH Köln

26.07.2017 | Event News

Closing the Sustainability Circle: Protection of Food with Biobased Materials

21.07.2017 | Event News

»We are bringing Additive Manufacturing to SMEs«

19.07.2017 | Event News

 
Latest News

Physicists gain new insights into nanosystems with spherical confinement

27.07.2017 | Materials Sciences

Seeing more with PET scans: New chemistry for medical imaging

27.07.2017 | Life Sciences

Did you know that infrared heat and UV light contribute to the success of your barbecue?

27.07.2017 | Power and Electrical Engineering

VideoLinks
B2B-VideoLinks
More VideoLinks >>>