|
New
Release -- Superconductor Week does not edit or endorse the following
news release:
Scientific Surprise Greets Researchers at Higher
Magnetic Fields
Tallahassee, FL, 21 March 2007: Research
performed by a team at Florida State University’s
National High Magnetic Field Laboratory suggests that the benefits of
building higher-field superconducting magnets likely will far outweigh the costs
of building them.
FSU researchers Riqiang Fu, Ozge Gunaydin-Sen and
Naresh Dalal discovered something they weren’t expecting while trying to improve
the resolution, or quality of image, in the magnet lab’s unique 900-megahertz,
21.1-tesla magnet. While experimenting with the giant magnet, the three noted an
exponential increase in the ease of detecting the “fingerprint” of the chemical
compound they were studying as they exposed it to ever-higher magnetic fields.
A paper describing their research was published
recently in the Journal of the American Chemical Society, a top-tier
chemistry journal. The paper can be accessed at
http://pubs.acs.org/cgibin/article.cgi/jacsat/2007/129/i03/pdf/ja067179j.pdf.
“This paper has very strong implications for the
United States staying ahead in magnet technology, which would bring great
dividends in research and improvements in medical imaging,” said Tim Cross,
director of the magnet lab’s NMR User Program and a professor of chemistry and
biochemistry at FSU. “We need — and are working on — additional fundamental
studies that show the benefits of going to higher fields.”
Nuclear magnetic resonance, or NMR, generates a
true-to-life fingerprint — a unique pattern indicating the presence of specific
molecules — for a research sample that is being analyzed. As a technique, NMR is
very accurate as long as one can detect the sample in the first place. The ease
or difficulty of detecting a sample is known as “sensitivity.” Low sensitivity
has been one of NMR’s biggest liabilities, because the lower
the sensitivity, the longer the experiment takes.
Such slowness has limited NMR’s potential applications.
“Poor signal is like a faint picture in the
darkness,” said Dalal, the Dirac Professor of Chemistry and Biochemistry at FSU.
“We’ve shown that the ‘900’ (magnet) increases the picture’s brightness by a
factor of about 10 relative to low-field images. Think of how much more you can
see in a room that is that much brighter ... and imagine what you’d see at even
higher fields.”
Theorists had predicted a linear increase in both
resolution and sensitivity at higher magnetic fields, moving from 14.1 tesla to
21.1 tesla, the current state of the art in superconducting magnets. In their
experiment, the FSU team members observed an exponential increase — with the
sensitivity increasing by a factor of three over what had been predicted.
Higher sensitivity in a magnet means it takes far
less time – or much less of a sample — to conduct an experiment.
“The reduction in time is like going from one
hour to a couple of minutes,” said Fu, an associate scholar/scientist at the
magnet lab and the FSU chemistry department. “Many experiments take weeks, and
such a reduction in time will allow for far more studies to be conducted on a
single instrument.”
Dalal said the shortening of experimental time
increases scientists’ ability to fingerprint materials, opening up new areas of
scientific investigation in NMR, including the study of materials useful in
nanotechnology and medical imaging. The need for less of a sample — up to 18
times less — will open up high-field NMR to the study of enzymes and purified
proteins, an area in which samples typically are of limited size.
The National High Magnetic Field Laboratory (http://www.magnet.fsu.edu)
develops and operates state-of-the-art, high-magnetic-field facilities that
faculty and visiting scientists and engineers use for interdisciplinary
research. The laboratory is sponsored by the National Science Foundation and the
state of Florida and is the only facility of its kind in the United States.
Return
to industry news releases |
