Iron oxide nanoparticles as agents for combined therapy and magnetic resonance imaging

Multifunctional iron-oxide based nanoparticles for magnetic fluidhyperthermia (MFH-therapy) and magnetic resonance imaging (MRI-diagnostics)have been investigated for their morpho-dimensional characteristics and relaxometricproperties. The nanoparticles were constituted of a spherical Fe3O4 core with diam-eter d = 19.2 ± 3.6 nm, coated with meso-2,3-dimercaptosuccinic acid (DMSA). The1H NMR results showed a longitudinal r1 relaxivity curve typical of high-anisotropymaterials and a transverse relaxivity that, at clinical field ?0H = 1.5 tesla, was ~3times higher than the one of commercial MRI contrast agents. The system displayeda SAR ~ 110 ± 30 W/gFe3O4 , i.e., high enough to allow for a successful combinationof MFH-assisted-hyperthermia and hadron therapy on pancreatic tumor cells.