title: Superparamagnetic Nanoparticles as High Efficiency Magnetic Resonance Imaging T2Contrast Agent.
abstract: Nanoparticle-based magnetic resonance imaging T2negative agents are of great interest, and much effort is devoted to increasing cell-loading capability while maintaining low cytotoxicity. Herein, two classes of mixed-ligand protected magnetic-responsive, bimetallic gold/iron nanoparticles (Au/Fe NPs) synthesized by a two-step method are presented. Their structure, surface composition, and magnetic properties are characterized. The two classes of sulfonated Au/Fe NPs, with an average diameter of 4 nm, have an average atomic ratio of Au to Fe equal to 7 or 8, which enables the Au/Fe NPs to be superparamagnetic with a blocking temperature of 56 K and 96 K. Furthermore, preliminary cellular studies reveal that both Au/Fe NPs show very limited toxicity. MRI phantom experiments show that r2/r1ratio of Au/Fe NPs is as high as 670, leading to a 66% reduction in T2relaxation time. These nanoparticles provide great versatility and potential for nanoparticle-based diagnostics and therapeutic applications and as imaging contrast agents.
authors.affiliation: Nanomedicine Laboratory, Fondazione IRCCS Istituto Neurologico Carlo Besta , AMADEOLAB, Via G.A. Amadeo 42, 20133 Milan, Italy.|IFOM The FIRC Institute of Molecular Oncology , Via Adamello 16, 20139 Milan, Italy.
authors.forename: Fernanda
authors.initials: F
authors.lastname: Sousa
authors.affiliation: Nanomedicine Laboratory, Fondazione IRCCS Istituto Neurologico Carlo Besta , AMADEOLAB, Via G.A. Amadeo 42, 20133 Milan, Italy.
authors.forename: Barbara
authors.identifier: 0000-0001-5837-4097
authors.initials: B
authors.lastname: Sanavio
authors.affiliation: Nanomedicine Laboratory, Fondazione IRCCS Istituto Neurologico Carlo Besta , AMADEOLAB, Via G.A. Amadeo 42, 20133 Milan, Italy.
authors.forename: Alessandra
authors.initials: A
authors.lastname: Saccani
authors.affiliation: Institute of Materials, Ecole Polytechnique Fédérale de Lausanne (EPFL) , Lausanne CH-1015, Switzerland.|Department of Chemistry, Laboratory of Advanced Materials, Fudan University , Shanghai 200433, China.
authors.forename: Yun
authors.initials: Y
authors.lastname: Tang
authors.affiliation: Laboratory of Experimental Imaging, Fondazione IRCCS Istituto Neurologico Carlo Besta , Via Celoria 11, 20133 Milan, Italy.
authors.forename: Ileana
authors.initials: I
authors.lastname: Zucca
authors.affiliation: Institute of Materials, Ecole Polytechnique Fédérale de Lausanne (EPFL) , Lausanne CH-1015, Switzerland.
authors.forename: Tamara M
authors.initials: TM
authors.lastname: Carney
authors.affiliation: Laboratory of Experimental Imaging, Fondazione IRCCS Istituto Neurologico Carlo Besta , Via Celoria 11, 20133 Milan, Italy.
authors.forename: Alfonso
authors.initials: A
authors.lastname: Mastropietro
authors.affiliation: Institute of Materials, Ecole Polytechnique Fédérale de Lausanne (EPFL) , Lausanne CH-1015, Switzerland.
authors.forename: Paulo H
authors.initials: PH
authors.lastname: Jacob Silva
authors.affiliation: Institute of Materials, Ecole Polytechnique Fédérale de Lausanne (EPFL) , Lausanne CH-1015, Switzerland.
authors.forename: Randy P
authors.initials: RP
authors.lastname: Carney
authors.affiliation: Laboratory of X-ray Diffraction, École Polytechnique Fédérale de Lausanne (EPFL) , Lausanne, CH-1015, Switzerland.
authors.forename: Kurt
authors.initials: K
authors.lastname: Schenk
authors.affiliation: Laboratory for Quantum Magnetism, École Polytechnique Fédérale de Lausanne (EPFL) , Lausanne, CH-1015, Switzerland.
authors.forename: Arash O
authors.initials: AO
authors.lastname: Omrani
authors.affiliation: Laboratory for Quantum Magnetism, École Polytechnique Fédérale de Lausanne (EPFL) , Lausanne, CH-1015, Switzerland.
authors.forename: Ping
authors.initials: P
authors.lastname: Huang
authors.affiliation: Laboratory for Quantum Magnetism, École Polytechnique Fédérale de Lausanne (EPFL) , Lausanne, CH-1015, Switzerland.
authors.forename: Lin
authors.initials: L
authors.lastname: Yang
authors.affiliation: Laboratory for Quantum Magnetism, École Polytechnique Fédérale de Lausanne (EPFL) , Lausanne, CH-1015, Switzerland.
authors.forename: Henrik M
authors.initials: HM
authors.lastname: Rønnow
authors.affiliation: Institute of Materials, Ecole Polytechnique Fédérale de Lausanne (EPFL) , Lausanne CH-1015, Switzerland.
authors.forename: Francesco
authors.identifier: 0000-0003-4635-6080
authors.initials: F
authors.lastname: Stellacci
authors.affiliation: Nanomedicine Laboratory, Fondazione IRCCS Istituto Neurologico Carlo Besta , AMADEOLAB, Via G.A. Amadeo 42, 20133 Milan, Italy.
authors.forename: Silke
authors.initials: S
authors.lastname: Krol
mesh_terms: D002455:Cell Division; D003287:Contrast Media / Q000737:chemistry*; D006046:Gold / Q000737:chemistry; D007501:Iron / Q000737:chemistry; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008280:Magnetics; D053768:Metal Nanoparticles; D046529:Microscopy, Electron, Transmission; D033362:Powder Diffraction
chemical_list: D003287:Contrast Media; D006046:Gold; D007501:Iron