Warming up for magnetic resonance imaging

"Doctors attempting to characterize tumors very often have to take biopsies, and that's painful for the patient, so they usually prefer to take only one biopsy," says Schröder. "But then they have to run all their tests on this very little tissue. So they would be happy with a method where you have a toolbox of sensors, you throw them all in and wait to let them bind, and then do your tests at the different frequencies and you see what sensors are present, detecting the different proteins. We showed that the exchange rate is so high at increased temperature that you can use a very selective rf pulse."

Enabling fast, sensitive, molecule-specific NMR and MRI in humans and other living subjects is perhaps the most evident advantage of the new technique, but possible applications don't end there. For example, the method offers a better way to study chemical exchange in nanostructures like zeolites, which are important in catalysis, or in versatile carbon nanotubes. Temperature-controlled depolarization is a breakthrough for NMR and MRI that will find uses in a variety of fields.

"Temperature-controlled molecular depolarization gates in nuclear magnetic resonance," by Leif Schröder, Lana Chavez, Tyler Meldrum, Monica Smith, Thomas J. Lowery, David E. Wemmer, and Alexander Pines, will soon appear in the international edition of Angewandte Chemie and is available online to subscribers at http://dx.doi.org/10.1002/anie.200800382.

This research was supported by the Department of Energy's Office of Science, Office of Basic Energy Sciences; by the Deutsche Forschungsgemeinschaft; and by the University of California's Biotechnology Research and Education Program.

Berkeley Lab is a U.S. Department of Energy national laboratory located in Berkeley, California. It conducts unclassified scientific research and is managed by the University of California. Visit our website at http://www.lbl.gov.

Additional information

For more about Hyper-CEST for high-contrast MRI, visit http://www.lbl.gov/Science-Articles/Archive/MSD-HYPER-CEST.html.

More about the design of xenon biosensors is at http://www.lbl.gov/Science-Articles/Archive/MSD-PBD-xenon-biosensor.html.

Visit the Alexander Pines laboratory at http://waugh.cchem.berkeley.edu/.

Visit the laboratory of the Wemmer Group at http://www.cchem.berkeley.edu/wemmer/Home.html.