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Abstract #1919

Hyperpolarization Quenching in 13C Nuclei Bound to Fast Relaxing Quadrupolar 14N Mediated by Scalar Coupling Relaxation in Amide Groups Exposed to Earth's Magnetic Field

Enrico Chiavazza1, 2, Eugen Kubala2, 3, Concetta V. Gringeri2, 4, Stephan Dwel2, 5, Markus Durst2, 5, Rolf F. Schulte2, Marion I. Menzel2

1Chemistry, University of Turin, Turin, Italy; 2GE Global Research, Munich, Germany; 3Johannes Kepler University, Linz, Austria; 4Klinik im Klinikum Rechts der Isar, Technische Universitt Mnchen, Munich, Germany; 5Institute of Medical Engineering, Technische Universitt Mnchen, Munich, Germany

Working on hyperpolarized [5-13C]glutamine, a fast liquid-state polarization quenching during the transfer to the MRI scanner has been observed. This behavior can be explained with a substantial 13C T1 shortening caused by scalar coupling relaxation contribution (type II) of the quadrupolar 14N in the amide group. This contribution is effective only low magnetic fields <800&[mu]T, impairing the use of 13C-amides as hyperpolarized MRS/MRI probes. It is shown that high hyperpolarization level can be retained either using 15N labeled amide or applying a sustained magnetic field during the transfer of the sample from the polarizer to the MRI scanner.

Keywords

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