New approach for understanding experimental NMR relaxivity properties of magnetic nanoparticles: focus on cobalt ferrite

作者：Rollet Anne Laure^*; Neveu Sophie; Porion Patrice; Dupuis Vincent; Cherrak Nadine; Levitz Pierre

来源：Physical Chemistry Chemical Physics, 2016, 18(48): 32981-32991.

DOI：10.1039/c6cp06012a

Relaxivities r(1) and r(2) of cobalt ferrite magnetic nanoparticles (MNPs) have been investigated in the aim of improving the models of NMR relaxation induced by magnetic nanoparticles. On one hand a large set of relaxivity data has been collected for cobalt ferrite MNP dispersions. On the other hand the relaxivity has been calculated for dispersions of cobalt ferrite MNPs with size ranging from 5 to 13 nm, without using any fitting procedure. The model is based on the magnetic dipolar interaction between the magnetic moments of the MNPs and the H-1 nuclei. It takes into account both the longitudinal and transversal contributions of the magnetic moments of MNPs leading to three contributions in the relaxation equations. The comparison of the experimental and theoretical data shows a good agreement of the NMR profiles as well as the temperature dependence.

• 出版日期2016