Nuclear magnetic resonance study of Gd-based nanoparticles totag boron compounds in boron neutron capture therapy

We report the investigation of new organic complexes containing a magnetic moment (Gd-based
molecular nanomagnets), which can serve the double purpose of acting as boron neutron capture
therapy (BNCT) agents, and at the same time act as contrast agents to detect the molecule in the
tissue by a proton magnetic resonance imaging (MRI). We also explore the possibility of
monitoring the concentration of the BNCT agent directly via proton and boron NMR relaxation.
The absorption of 10B-enriched molecules inside tumoral liver tissues has been shown by NMR
measurements and confirmed by a spectroscopy. A new molecular Gd-tagged nanomagnet and
BNCT agent (GdBPA) has been synthesized and characterized measuring its relaxivity R1 between
10 kHz and 66 MHz, and its use as a contrast agent in MRI has been demonstrated. The
NMR-based evidence of the absorption of GdBPA into living tumoral cells is also shown.