Get access

15N-Permethylated amino acids as efficient probes for MRI-DNP applications


Correspondence to: A. Silvio, Department of Chemistry and Center for Molecular ImagingUniversity of TurinVia Nizza 52, 10125 Torino, Italy. E-mail:


The synthesis, NMR properties and preliminary polarization tests on protonated and perdeuterated forms of α-trimethylglutamine (NMe3Gln), α-trimethylglutamate (NMe3Glu) and ε-trimethyllysine (NMe3Lys) are reported. The 15N-permethylated, perdeuterated amino acids display very long 15N-T1 values, ranging between 190 and 330 s, are well polarized by the dynamic nuclear polarization (DNP) procedure, yielding good polarization levels (10%), and appear to be well tolerated by cells and mice. The obtained results make perdeuterated amino acids excellent candidates for innovative DNP 15N-MRI applications such as perfusion or targeting studies. Copyright © 2013 John Wiley & Sons, Ltd.