With support from the Chemical Measurement and Imaging Program in the Division of Chemistry, and co-funding from the Atomic, Molecular, and Optical Experimental Physics Program in the Division of Physics, Professor Warren Warren and his group at Duke University are working to expand the utility and accessibility of ?hyperpolarized? nuclear magnetic resonance (NMR) spectroscopy. NMR is a powerful tool for chemists; it is useful for determining molecular structure and for monitoring the progress of chemical reactions. NMR's clinical cousin, magnetic resonance imaging (MRI) is an important tool for producing images of soft tissues in the body. However, both methods usually suffer from low sensitivity - meaning that they cannot detect small amounts of sample or low concentrations. "Hyperpolarization" methods can increase NMR signals by a factor of 1000 or more, but are usually technically challenging and extremely expensive. The Warren group is exploring the fundamental chemistry and physics behind new strategies with prospects of providing routine hyperpolarization as a simple and cost-effective add-on to any NMR spectrometer. The team is also providing research and training opportunities in these critical technologies for members of underrepresented groups, and providing substantial K-12 science outreach.
The Warren group studies the production, quantum statistical mechanics, and characterization of hyperpolarized, long-lived nuclear spin states in NMR and MRI. They seek to drastically improve the generality, fractional polarization, and absolute polarization levels of nuclei such as 15N, 13C and 19F from parahydrogen gas (p-H2) in solution, without chemical reaction, thereby enabling applications ranging from quantifying rotational-state effects on reactivity in solution to dark matter detection. The ability to make and store large quantities of p-H2 should enable creation of massively large (kg size) continuously hyperpolarized targets which can serve as ultrasensitive magnetometers (e.g. for dark matter detection) or can drastically reduce the size of the magnets needed for clinical MRI. Applicability can also be expanded by the ability to make p-H2 at the L-atm/hour level using a simple, inexpensive laboratory apparatus. While ultra-low-field NMR is not new, this work aims to bring it into the mainstream, while also enabling better high-field experiments. The aim is to reduce or eliminate the cost and complexity barriers to implementation of hyperpolarization.
This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.
