title: Developing Fe3O4 nanoparticles into an efficient multimodality imaging and therapeutic probe.
abstract: A rapid ligand-exchange method was developed to transfer high quality hydrophobic magnetite nanocrystals into water-soluble NPs by using protocatechuic acid as a ligand via homogenous reaction. After ligand exchange, the magnetite nanocrystals not only exhibited outstanding stability in water, but also maintained high crystallinity and saturation magnetization. Cell viability experiments demonstrated good biocompatibility of the NPs. For 12 nm magnetite nanoparticles (NPs), the small hydrodynamic size of 14 nm enabled a high T1 relaxivity of 17.8 mM(-1) s(-1) while high saturation magnetization of 77.8 emu g(-1) enabled the NPs to exhibit a high T2 relaxivity of 220 mM(-1) s(-1) in MRI phantom experiments. In vivo MR imaging experiments further confirmed that the NPs were eminent T1 and T2 contrast agents. Moreover, the high quality NPs can be used as excellent magnetic heating agents under an alternating magnetic field. With all those features, including multimodality imaging and magnetic hyperthermia, the NPs can be used as single compound multifunctional agents for various biomedical applications, especially for cancer diagnosis and therapy.
authors.affiliation: Department of Materials Science and Engineering, College of Engineering, Peking University, Beijing 100871, China. hou@pku.edu.cn.
authors.forename: Rui
authors.initials: R
authors.lastname: Hao
authors.forename: Jing
authors.initials: J
authors.lastname: Yu
authors.forename: Zigang
authors.initials: Z
authors.lastname: Ge
authors.forename: Lingyun
authors.initials: L
authors.lastname: Zhao
authors.forename: Fugeng
authors.initials: F
authors.lastname: Sheng
authors.forename: Lili
authors.initials: L
authors.lastname: Xu
authors.forename: Gongjie
authors.initials: G
authors.lastname: Li
authors.forename: Yanglong
authors.initials: Y
authors.lastname: Hou
mesh_terms: D000818:Animals; D002470:Cell Survival / Q000187:drug effects; D003287:Contrast Media / Q000737:chemistry* / Q000494:pharmacology; D052203:Ferrosoferric Oxide / Q000737:chemistry*; D006367:HeLa Cells; D006801:Humans; D057927:Hydrophobic and Hydrophilic Interactions; D062385:Hydroxybenzoates / Q000737:chemistry; D008113:Liver Neoplasms / Q000000981:diagnostic imaging; D008279:Magnetic Resonance Imaging; D058185:Magnetite Nanoparticles / Q000737:chemistry*; D051379:Mice; D008807:Mice, Inbred BALB C; D011817:Rabbits; D011859:Radiography; D014183:Transplantation, Heterologous; D014867:Water / Q000737:chemistry
chemical_list: D003287:Contrast Media; D062385:Hydroxybenzoates; D058185:Magnetite Nanoparticles; D014867:Water; C009091:protocatechuic acid; D052203:Ferrosoferric Oxide