General protocol for the synthesis of functionalized magnetic nanoparticles for magnetic resonance imaging from protected metal-organic precursors.
The development of magnetic nanoparticles (MNPs) with functional groups has been intensively pursued in recent years. Herein, a simple, versatile, and cost-effective strategy to synthesize water-soluble and amino-functionalized MNPs, based on the thermal decomposition of phthalimide-protected metal-organic precursors followed by deprotection, was developed. The resulting amino-functionalized Fe3O4, MnFe2O4, and Mn3O4 MNPs with particle sizes of about 14.3, 7.5, and 6.6 nm, respectively, had narrow size distributions and good dispersibility in water. These MNPs also exhibited high magnetism and relaxivities of r2 = 107.25 mM(-1)  s(-1) for Fe3O4, r2 = 245.75 mM(-1)  s(-1) for MnFe2O4, and r1 = 2.74 mM(-1)  s(-1) for Mn3O4. The amino-functionalized MNPs were further conjugated with a fluorescent dye (rhodamine B) and a targeting ligand (folic acid: FA) and used as multifunctional probes. Magnetic resonance imaging and flow-cytometric studies showed that these probes could specifically target cancer cells overexpressing FA receptors. This new protocol opens a new way for the synthesis and design of water-soluble and amino-functionalized MNPs by an easy and versatile route.
The Key Laboratory of the Resource Chemistry of Ministry of Education and the Shanghai Key Laboratory of the Rare Earth Functional Materials, Department of Chemistry, Shanghai Normal University, No. 100 Guilin Road, Shanghai, 200234 (P. R. China), Fax: (+86) 21-64322511.
He
H
Hu
Chongkun
C
Zhang
Lu
L
An
Yanrong
Y
Yu
Hong
H
Yang
Jin
J
Sun
Huixia
H
Wu
Shiping
S
Yang
D017209:Apoptosis / Q000187:drug effects; D005290:Ferric Compounds / Q000737:chemistry; D052203:Ferrosoferric Oxide / Q000737:chemistry; D005434:Flow Cytometry; D005456:Fluorescent Dyes / Q000737:chemistry; D005492:Folic Acid / Q000737:chemistry; D006367:HeLa Cells; D006801:Humans; D061986:MCF-7 Cells; D008279:Magnetic Resonance Imaging; D058185:Magnetite Nanoparticles / Q000737:chemistry* / Q000633:toxicity; D017895:Manganese Compounds / Q000737:chemistry; D008670:Metals / Q000737:chemistry*; D010087:Oxides / Q000737:chemistry; D010316:Particle Size; D010797:Phthalimides / Q000737:chemistry*; D012235:Rhodamines / Q000737:chemistry
D005290:Ferric Compounds; D005456:Fluorescent Dyes; D058185:Magnetite Nanoparticles; D017895:Manganese Compounds; D008670:Metals; D010087:Oxides; D010797:Phthalimides; D012235:Rhodamines; C551151:manganese ferrite; C037431:phthalimide; C027424:manganese oxide; D005492:Folic Acid; C029773:rhodamine B; D052203:Ferrosoferric Oxide
imaging agents; magnetic properties; magnetic resonance imaging; nanoparticles; protecting groups