Ultra-small, Uniform, and Single bcc-Phased FexCo1-x/Graphitic Shell Nanocrystals for T-1 Magnetic Resonance Imaging Contrast Agents

作者：Choi In Ae; Li Yan; Kim Da Jeong; Pal Mou; Cho Jee Hyun; Lee Kyujoon; Jung Myung Hwa; Lee Chulhyun; Seo Won Seok^*

来源：Chemistry-An Asian Journal, 2013, 8(1): 290-295.

DOI：10.1002/asia.201200950

• alloys
• graphitic shell
• magnetic resonance
• mesoporous materials
• nanoparticles

We have synthesized ultrasmall and uniform FexCo1-x/graphitic carbon shell (FexCo1-x/GC) nanocrystals (x=0.13, 0.36, 0.42, 0.50, 0.56, and 0.62, respectively) with average diameters of %26lt;4 nm by thermal decomposition of metal precursors in approximately 60 nm MCM-41 and methane CVD. The composition of the FexCo1-x/GC nanocrystals can be tuned by changing the Fe:Co ratios of the metal precursors. The FexCo1-x/GC nanocrystals show superparamagnetic properties at room temperature. The Fe0.50Co0.50/GC, Fe0.56Co0.44/GC, and Fe0.62Co0.38/GC nanocrystals have a single bcc FeCo structure, whereas the Fe0.13Co0.87/GC, Fe0.36Co0.64/GC, and Fe0.42Co0.58/GC nanocrystals have a mixed structure of bcc FeCo and fcc Co. The single bcc-phased FexCo1-x/GC nanocrystals functionalized with phospholipid-poly(ethylene glycol) (PL-PEG) in phosphate buffered saline (PBS) are demonstrated to be excellent T-1 MRI contrast agents.

• 出版日期2013-1