title: A sub-50-nm monosized superparamagnetic Fe3O4@SiO2 T2-weighted MRI contrast agent: highly reproducible synthesis of uniform single-loaded core-shell nanostructures.
abstract: Oleic acid stabilized superparamagnetic iron oxide nanoparticles (SPION) were selected as the cores for fabrication of sub-50-nm monodisperse single-loaded SPION@SiO2 core-shell nanostructures. Parameters that influence the formation of SPION@SiO2 in the water-in-oil reverse microemulsion system have been systematically investigated. The sufficiently high concentration of well-dispersed SPION, together with an appropriately low injection rate of tetraethoxysilane, were found to be the keys to efficiently prevent the homogeneous nucleation of silica and obtain a high-quality single-loaded core-shell nanocomposite. A more detailed mechanism for incorporating oleic acid capped inorganic functional nanoparticles into silica is proposed on the basis of previous reports and our new experimental results. Finally, the as-synthesized SPION@SiO2 nanospheres are exploited as an MRI-enhanced contrast agent, and their contrast effect in solution is tested by using a clinical MRI instrument.
authors.affiliation: State Key Laboratory of High Performance Ceramics and Superfine Microstructures, Shanghai Institute of Ceramics, Chinese Academy of Sciences, Shanghai, 200050 (P.R. China), Fax:(+86) 21-52413122.
authors.forename: Feng
authors.initials: F
authors.lastname: Chen
authors.affiliation: State Key Laboratory of High Performance Ceramics and Superfine Microstructures, Shanghai Institute of Ceramics, Chinese Academy of Sciences, Shanghai, 200050 (P.R. China), Fax:(+86) 21-52413122.
authors.forename: Wenbo
authors.initials: W
authors.lastname: Bu
authors.affiliation: State Key Laboratory of High Performance Ceramics and Superfine Microstructures, Shanghai Institute of Ceramics, Chinese Academy of Sciences, Shanghai, 200050 (P.R. China), Fax:(+86) 21-52413122.
authors.forename: Yu
authors.initials: Y
authors.lastname: Chen
authors.affiliation: State Key Laboratory of High Performance Ceramics and Superfine Microstructures, Shanghai Institute of Ceramics, Chinese Academy of Sciences, Shanghai, 200050 (P.R. China), Fax:(+86) 21-52413122.
authors.forename: Yuchi
authors.initials: Y
authors.lastname: Fan
authors.affiliation: State Key Laboratory of High Performance Ceramics and Superfine Microstructures, Shanghai Institute of Ceramics, Chinese Academy of Sciences, Shanghai, 200050 (P.R. China), Fax:(+86) 21-52413122.
authors.forename: Qianjun
authors.initials: Q
authors.lastname: He
authors.affiliation: State Key Laboratory of High Performance Ceramics and Superfine Microstructures, Shanghai Institute of Ceramics, Chinese Academy of Sciences, Shanghai, 200050 (P.R. China), Fax:(+86) 21-52413122.
authors.forename: Min
authors.initials: M
authors.lastname: Zhu
authors.affiliation: Department of Radiology, Shanghai Cancer Hospital, Fudan University, Shanghai 200032 (P.R. China).
authors.forename: Xiaohang
authors.initials: X
authors.lastname: Liu
authors.affiliation: Department of Radiology, Shanghai Cancer Hospital, Fudan University, Shanghai 200032 (P.R. China).
authors.forename: Liangping
authors.initials: L
authors.lastname: Zhou
authors.affiliation: Department of Radiology, Shanghai Cancer Hospital, Fudan University, Shanghai 200032 (P.R. China).
authors.forename: Shengjian
authors.initials: S
authors.lastname: Zhang
authors.affiliation: Department of Radiology, Shanghai Cancer Hospital, Fudan University, Shanghai 200032 (P.R. China).
authors.forename: Weijun
authors.initials: W
authors.lastname: Peng
authors.affiliation: State Key Laboratory of High Performance Ceramics and Superfine Microstructures, Shanghai Institute of Ceramics, Chinese Academy of Sciences, Shanghai, 200050 (P.R. China), Fax:(+86) 21-52413122.
authors.forename: Jianlin
authors.initials: J
authors.lastname: Shi
mesh_terms: D000327:Adsorption; D003287:Contrast Media / Q000737:chemistry; D003911:Dextrans; D005290:Ferric Compounds / Q000737:chemistry*; D052203:Ferrosoferric Oxide; D018810:Magnetic Resonance Angiography / Q000379:methods*; D008279:Magnetic Resonance Imaging; D008280:Magnetics; D058185:Magnetite Nanoparticles; D049329:Nanostructures / Q000737:chemistry*; D019301:Oleic Acid / Q000737:chemistry; D012822:Silicon Dioxide / Q000737:chemistry
chemical_list: D003287:Contrast Media; D003911:Dextrans; D005290:Ferric Compounds; D058185:Magnetite Nanoparticles; C000499:ferric oxide; D019301:Oleic Acid; D012822:Silicon Dioxide; C065507:ferumoxides; D052203:Ferrosoferric Oxide