Polymer-coated silver-iron nanoparticles as efficient and biodegradable MRI contrast agents

• Published in: Journal of colloid and interface science 2021-08, Vol.596, p.332-341
• Main Authors: Amendola, Vincenzo, Guadagnini, Andrea, Agnoli, Stefano, Badocco, Denis, Pastore, Paolo, Fracasso, Giulio, Gerosa, Marco, Vurro, Federica, Busato, Alice, Marzola, Pasquina
• Format: Article
• Language: English
• Subjects: Bimetallic nanoparticles; Laser ablation; MRI, biodegradation; Silver nanoparticles
• ISSN: 0021-9797; 1095-7103
• DOI: 10.1016/j.jcis.2021.03.096

[Display omitted] Bimetallic nanoparticles allow new and synergistic properties compared to the monometallic equivalents, often leading to unexpected results. Here we present on silver-iron nanoparticles coated with polyethylene glycol, which exhibit a high transverse relaxivity (316 ± 13 mM-1s−1, > 3 times that of the most common clinical benchmark based on iron oxide), excellent colloidal stability and biocompatibility in vivo. Ag-Fe nanoparticles are obtained through a one-step, low-cost laser-assisted synthesis, which makes surface functionalization with the desired biomolecules very easy. Besides, Ag-Fe nanoparticles show biodegradation over a few months, as indicated by incubation in the physiological environment. This is crucial for nanomaterials removal from the living organism and, in fact, in vivo biodistribution studies evidenced that Ag-Fe nanoparticles tend to be cleared from liver over a period in which the benchmark iron oxide contrast agent persisted. Therefore, the Ag-Fe NPs offer positive prospects for solving the problems of biopersistence, contrast efficiency, difficulties of synthesis and surface functionalization usually encountered in nanoparticulate contrast agents.