title: Gold-coated iron oxide nanoparticles as a T2 contrast agent in magnetic resonance imaging.
abstract: Gold-coated iron oxide (Fe3O4) nanoparticles were synthesized for use as a T2 contrast agent in magnetic resonance imaging (MRI). The coated nanoparticles were spherical in shape with an average diameter of 20 nm. The gold shell was about 2 nm thick. The bonding status of the gold on the nanoparticle surfaces was checked using a Fourier transform infrared spectrometer (FTIR). The FTIR spectra confirmed the attachment of homocysteine, in the form of thiolates, to the Au shell of the Au-Fe3O4 nanoparticles. The relaxivity ratio, R2/R1, for the coated nanoparticles was 3-fold higher than that of a commercial contrast agent, Resovist, which showed the potential for their use as a T2 contrast agent with high efficacy. In animal experiments, the presence of the nanoparticles in rat liver resulted in a 71% decrease in signal intensity in T2-weighted MR images, indicating that our gold-coated iron oxide nanoparticles are suitable for use as a T2 contrast agent in MRI.
authors.affiliation: Department of Physics, Kyungpook National University, Daegu, 702-701, Korea.
authors.forename: Tanveer
authors.initials: T
authors.lastname: Ahmad
authors.forename: Hongsub
authors.initials: H
authors.lastname: Bae
authors.forename: Ilsu
authors.initials: I
authors.lastname: Rhee
authors.forename: Yongmin
authors.initials: Y
authors.lastname: Chang
authors.forename: Seong-Uk
authors.initials: SU
authors.lastname: Jin
authors.forename: Sungwook
authors.initials: S
authors.lastname: Hong
mesh_terms: D000818:Animals; D020099:Coated Materials, Biocompatible / Q000737:chemistry; D003287:Contrast Media / Q000138:chemical synthesis; D006046:Gold / Q000737:chemistry; D008099:Liver / Q000033:anatomy & histology*; D008279:Magnetic Resonance Imaging / Q000379:methods*; D058185:Magnetite Nanoparticles / Q000737:chemistry; D008422:Materials Testing; D051381:Rats
chemical_list: D020099:Coated Materials, Biocompatible; D003287:Contrast Media; D058185:Magnetite Nanoparticles; D006046:Gold