(Press-News.org) Washington, D.C. (November 30, 2010) -- Nuclear magnetic resonance (NMR) is one of the best tools for gaining insight into the structure and dynamics of molecules because nuclei in atoms within molecules will behave differently in a variety of chemical environments. Nuclei can be thought of as tiny compasses that align when placed in the field of a strong magnet. Similar to magnetic resonance imaging (MRI), conventional NMR uses short pulses of radio waves to drive nuclei away from equilibrium and a 'signal' emerges as nuclei slowly realign with the field.
Results reported in The Journal of Chemical Physics introduce an alternative path to this information, by using light to observe nuclei indirectly via the orbiting electrons.
"We are not looking at a way to replace the conventional technique but there are a number of applications in which optical detection could provide complementary information," says author Carlos Meriles of the City University of New York.
The new technique is based on Optical Faraday Rotation (OFR), a phenomenon in which the plane of linearly polarized light rotates upon crossing a material immersed in a magnetic field. When nuclei are sufficiently polarized, the extra magnetic field they produce is 'felt' by the electrons in the sample thus leading to Faraday rotation of their own. Because the interaction between electrons and nuclei depends on the local molecular structure, OFR-detected NMR spectroscopy provides complementary information to conventional detection.
Another interesting facet of the technique is that, unlike conventional NMR, the signal response is proportional to the sample length, but not its volume. "Although we have not yet demonstrated it, our calculations show that we could magnify the signal by creating a very long optical path in a short, thin tube," Meriles says. This signal magnification would use mirrors at both ends of a channel in a microfluidics device to reflect laser light repeatedly through the sample, increasing the signal amplitude with each pass.
INFORMATION:
The article, "Time-resolved, optically-detected NMR of fluids at high magnetic field" by Daniela Pagliero, Wei Dong, Dimitris Sakellariou, and Carlos A. Meriles appears in The Journal of Chemical Physics. See: http://link.aip.org/link/jcpsa6/v133/i15/p154505/s1
Journalists may request a free PDF of this article by contacting jbardi@aip.org
ABOUT THE JOURNAL OF CHEMICAL PHYSICS
The Journal of Chemical Physics publishes concise and definitive reports of significant research in methods and applications of chemical physics. Innovative research in traditional areas of chemical physics such as spectroscopy, kinetics, statistical mechanics, and quantum mechanics continue to be areas of interest to readers of JCP. In addition, newer areas such as polymers, materials, surfaces/interfaces, information theory, and systems of biological relevance are of increasing importance. Routine applications of chemical physics techniques may not be appropriate for JCP. Content is published online daily, collected into four monthly online and printed issues (48 issues per year); the journal is published by the American Institute of Physics. See: http://jcp.aip.org/
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The American Institute of Physics is a federation of 10 physical science societies representing more than 135,000 scientists, engineers, and educators and is one of the world's largest publishers of scientific information in the physical sciences. Offering partnership solutions for scientific societies and for similar organizations in science and engineering, AIP is a leader in the field of electronic publishing of scholarly journals. AIP publishes 12 journals (some of which are the most highly cited in their respective fields), two magazines, including its flagship publication Physics Today; and the AIP Conference Proceedings series. Its online publishing platform Scitation hosts nearly two million articles from more than 185 scholarly journals and other publications of 28 learned society publishers.
Washington, D.C. (November 30, 2010) -- One of the holy grails of nanotechnology in medicine is to control individual structures and processes inside a cell. Nanoparticles are well suited for this purpose because of their small size; they can also be engineered for specific intracellular tasks. When nanoparticles are excited by radio-frequency (RF) electromagnetic fields, interesting effects may occur. For example, the cell nucleus could get damaged inducing cell death; DNA might melt; or protein aggregates might get dispersed.
Some of these effects may be due to the ...
Washington, D.C. (November 30, 2010) -- Quantum information processing is arguably one of the most fascinating facets of modern quantum physics.
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Now, researchers in Germany have successfully ...
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SEATTLE – The worst global economic crisis in decades has not stopped public and private donors from giving record amounts of money to health assistance for developing countries, according to a new report by the Institute for Health Metrics and Evaluation (IHME) at the University of Washington.
The research shows that development assistance for health has grown 375% from $5.66 billion in 1990 to $26.87 billion in 2010. However, IHME's preliminary estimates show that the growth rate is slowing. Between 2004 and 2008, the period of the most dramatic increases in health funding, ...
The fragile regions in mammalian genomes that are thought to play a key role in evolution go through a "birth and death" process, according to new bioinformatics research performed at the University of California, San Diego. The new work, published in the journal Genome Biology on November 30, could help researchers identify the current fragile regions in the human genome – information that may reveal how the human genome will evolve in the future.
"The genomic architecture of every species on Earth changes on the evolutionary time scale and humans are not an exception. ...
VIDEO:
Dr. Daniel Kelly describes how mice without the protein PGC-1 lose the ability to exercise.
Click here for more information.
ORLANDO, Fla., November 30, 2010 – Daniel Kelly, M.D., and his colleagues at Sanford-Burnham Medical Research Institute (Sanford-Burnham) at Lake Nona have unveiled a surprising new model for studying muscle function: the couch potato mouse. While these mice maintain normal activity and body weight, they do not have the energy to exercise. In the ...
BEER-SHEVA, ISRAEL, November 30, 2010 -- "Good looks" are only sometimes a positive factor in consideration for a job, according to new research from Ben-Gurion University of the Negev (BGU). In the new working paper, "Are Good-Looking People More Employable?" two economics researchers from BGU prove that a double standard exists between good looks as a positive factor in men and women.
The research involved sending 5,312 CVs (resumes) in pairs to 2,656 advertised job openings in Israel. In each pair, one CV was without a picture while the second, otherwise almost identical ...
Geo-microbiologists from Arizona State University have solved a long-standing conundrum about how some photosynthetic microorganisms, endolithic cyanobacteria, bore their way into limestone, sand grains, mussel shells, coral skeletons and other substrates composed of carbonate.
According to the lead investigator, ASU professor Ferran Garcia-Pichel, the answer to the mystery of what is "at the heart of an erosive force of global proportions" is a calcium-driven pump, similar to that which we use to power our muscles.
The results of Garcia-Pichel's study "Microbial excavation ...
Jerusalem, November 30, 2010 – Researchers at the Hebrew University of Jerusalem who have been examining what happens in a "model earthquake" in their laboratory have discovered that basic assumptions about friction that have been accepted for hundreds of years are just wrong. Their findings provide a new means for replicating how earth ruptures develop and possibly enabling prediction of coming severe earthquakes.
"The findings have a wide variety of implications for materials science and engineering and could help researchers understand how earthquakes occur and how ...
Coping with chronic pain can affect every aspect of a person's life and cause conflict between what their mind wants to achieve and what their body allows them to do, according to research in the December issue of the Journal of Nursing and Healthcare of Chronic Illness.
Swedish researchers carried out in-depth interviews with ten people who had experienced chronic pain for between four and 32 years and were taking part in an outpatient rehabilitation programme. Nine of the patients, who ranged from 22 to 50 with an average age of 38, were unable to work because of their ...
