Protein-Nanoparticle Material Mimics Human Brain Tissue

July 21, 2006 feature

A composite material consisting of a horse protein and metallic nanoparticles displays magnetic properties very similar to those of human brain tissue, scientists have found. The work, published in the June 20 online edition of Physical Review B, may help lead to a more thorough understanding of the magnetic behavior of brain tissue and other complex natural materials.

Studying the magnetism of many natural substances, such as rocks, soils, and biological materials, can be difficult because they tend to be a mix of several magnetic components. This means that valuable structural and functional information, which can be obtained from a material’s magnetic properties, is often left undiscovered.

“It can be very difficult to separate the different components to study them individually,” said the study’s lead scientist, geophysicist Ann Hirt, to PhysOrg.com. Hirt is a researcher at the Institute of Geophysics in Zurich, Switzerland. “Often, the use of several analysis methods is necessary and, even then, definite conclusions are seldom. Finding and investigating model materials may help remedy this problem.”

As a first step, Hirt and her team identified the different components in the brain that produce magnetic signals. They used various magnetic methods, which are normally used to identify magnetic minerals in rocks. They found that the brain tissue, in which the other components are embedded, contributes the strongest magnetic signal, followed by iron in the blood of the brain. Next is ferritin, an iron-carrying protein found in nanoparticle form. Recently, a fourth component was discovered, but its identity has eluded scientists. It is either the iron-oxygen compound magnetite or a very similar compound, maghemite — or perhaps even a blend of the two. Magnetite and maghemite have such similar magnetic properties that distinguishing between them is very difficult.

“Although the signal from the tissue itself was very strong, we could easily subtract it from the total magnetization,” said Franziska Brem, another Institute of Geophysics scientist geophysicist on the team. “The remaining signal appeared to be a combination of the signals from ferritin and magnetite.”

To confirm this, the group measured the magnetic properties of a model system for which they knew the exact content and that they could study with certainty: a mixture of horse-spleen ferritin and protein-coated magnetite nanoparticles. The results show a striking similarity to the measurements for actual brain tissue.

“Based on these measurements, we can assume that the ferritin and magnetite/maghemite behavior in brain tissue is very close to that of our model material,” Brem said.

By Laura Mgrdichian, Copyright 2006 PhysOrg.com

Explore further: Novel MRI technique distinguishes healthy prostate tissue from cancer using zinc

Related Stories

New MRI technique sheds technology's longtime limits

August 16, 2016

A new technology harnesses imperfections that typically compromise MRI exams to create images resolved enough to enable consistent diagnoses across populations for the first time. These are findings of a study led by NYU ...

Recommended for you

Understanding nature's patterns with plasmas

August 23, 2016

Patterns abound in nature, from zebra stripes and leopard spots to honeycombs and bands of clouds. Somehow, these patterns form and organize all by themselves. To better understand how, researchers have now created a new ...

Measuring tiny forces with light

August 25, 2016

Photons are bizarre: They have no mass, but they do have momentum. And that allows researchers to do counterintuitive things with photons, such as using light to push matter around.

Light and matter merge in quantum coupling

August 22, 2016

Where light and matter intersect, the world illuminates. Where light and matter interact so strongly that they become one, they illuminate a world of new physics, according to Rice University scientists.

Stretchy supercapacitors power wearable electronics

August 23, 2016

A future of soft robots that wash your dishes or smart T-shirts that power your cell phone may depend on the development of stretchy power sources. But traditional batteries are thick and rigid—not ideal properties for ...

Spherical tokamak as model for next steps in fusion energy

August 24, 2016

Among the top puzzles in the development of fusion energy is the best shape for the magnetic facility—or "bottle"—that will provide the next steps in the development of fusion reactors. Leading candidates include spherical ...

0 comments

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.