Monodisperse magnetite nanoparticles with high sensitivity as MRI contrast agents

Ernesto Amato, Paola Lanzafame, Antonio S. Italiano, Giuseppe Cicero, Georgia Papanikolaou, Siglinda Perathoner, Gabriele Centi, Fabio Minutoli

Abstract


The preparation of monodisperse and biocompatible water-soluble super-paramagnetic iron oxide nanoparticles (SPIONs) with high sensitivity in Magnetic Resonance Imaging (MRI) represents a challenge for the development of contrast agents. Here we report the synthesis of highly monodisperse citric acid (CA) coated SPIONs with an average diameter of 9 nm and spherical shape, prepared through a suitably optimized coprecipitation method. CA-SPIONs show a high solubility and stability in aqueous medium. Imaging of CA-SPIONs aqueous suspensions was performed in a clinical 1.5-T MRI scanner and different clinical acquisition sequences were exploited. Results show that image contrast can be effectively improved when concentrations of SPIONs lower than 1 ppm are present, and that the echo time is the main parameter influencing the image contrast of SPION-loaded solutions. Moreover, we found that CA-SPIONs show a high value of transverse relaxivity of 128 L mmol-1 s-1 (higher than the commercial contrast agents). Our results are encouraging for the further development of clinical application of SPIONs in MRI, and can represent a starting point for the optimization of clinical imaging exploiting the contrast enhancement of such agents. Namely, it seems possible to achieve an optimal image contrast with low concentration of SPIONs; this could lead to a lower probability of side effects.

Keywords


Contrast agents, super-paramagnetic nanoparticle, magnetic resonance imaging

Full Text:

PDF


DOI: http://dx.doi.org/10.1478/AAPP.962A5

Copyright (c) 2018 Ernesto Amato, Paola Lanzafame, Antonio S. Italiano, Giuseppe Cicero, Georgia Papanikolaou, Siglinda Perathoner, Gabriele Centi, Fabio Minutoli

Creative Commons License
This work is licensed under a Creative Commons Attribution 4.0 International License.