title: Controlled aggregates of magnetite nanoparticles for highly sensitive MR contrast agent.
abstract: We have prepared a magnetite encapsulated polymer nanocomposite (MEPN) by an emulsification-diffusion technique and found that the encapsulation efficiency could be precisely controlled according to the portion of magnetite and the capping ligand that covers the surface of the magnetite nanoparticles. The field-dependence and temperature dependence on magnetization, measured by a superconducting quantum interference device, demonstrate that there was no size effect of the magnetite nanoparticles on the encapsulation behavior. The size distribution and T2 relaxivity of prepared MEPNs were measured using magnetic resonance imaging for analysis of the effect of aggregation and it was verified that aggregates of the magnetite nanoparticles provide enhanced relaxation ability.
authors.affiliation: Department of Chemical and Biomolecular Engineering (BK 21 program), Center for Energy and Environment Research, KAIST, Daejeon 305-701, South Korea.
authors.forename: Bong-Sik
authors.initials: BS
authors.lastname: Jeon
authors.forename: Eun-Jin
authors.initials: EJ
authors.lastname: Cho
authors.forename: Hee-Man
authors.initials: HM
authors.lastname: Yang
authors.forename: Jin-Suck
authors.initials: JS
authors.lastname: Suh
authors.forename: Yong-Min
authors.initials: YM
authors.lastname: Huh
authors.forename: Jong-Duk
authors.initials: JD
authors.lastname: Kim
mesh_terms: D003287:Contrast Media / Q000138:chemical synthesis*; D003460:Crystallization / Q000379:methods; D052203:Ferrosoferric Oxide / Q000737:chemistry*; D007089:Image Enhancement / Q000379:methods*; D046911:Macromolecular Substances / Q000737:chemistry; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008422:Materials Testing; D008968:Molecular Conformation; D053758:Nanoparticles / Q000737:chemistry* / Q000648:ultrastructure; D036103:Nanotechnology / Q000379:methods; D010316:Particle Size; D013499:Surface Properties
chemical_list: D003287:Contrast Media; D046911:Macromolecular Substances; D052203:Ferrosoferric Oxide