Skip Navigation



Journal of Electron Microscopy Advance Access published online on November 6, 2009
Journal of Electron Microscopy, doi:10.1093/jmicro/dfp055
This Article
Right arrow Full Text
Right arrow Full Text (PDF)
Right arrow Supplementary Data
Right arrow Alert me when this article is cited
Right arrow Alert me if a correction is posted
Services
Right arrow Email this article to a friend
Right arrow Similar articles in this journal
Right arrow Similar articles in PubMed
Right arrow Alert me to new issues of the journal
Right arrow Add to My Personal Archive
Right arrow Download to citation manager
Right arrowRequest Permissions
Google Scholar
Right arrow Articles by Okuda, M.
Right arrow Articles by Ikoma, T.
PubMed
Right arrow PubMed Citation
Right arrow Articles by Okuda, M.
Right arrow Articles by Ikoma, T.
Social Bookmarking
Add to CiteULike   Add to Connotea   Add to Del.icio.us  
What's this?

© The Author 2009. Published by Oxford University Press on behalf of Japanese Society of Microscopy. All rights reserved. For permissions, please e-mail: journals.permissions@oxfordjournals.org

Structural analysis of hydroxyapatite coating on magnetite nanoparticles using energy filter imaging and electron tomography

Mitsuhiro Okuda1,2, Masaki Takeguchi2, Órla Ó Ruairc3, Motohiro Tagaya1, Yufang Zhu4, Ayako Hashimoto4, Nobutaka Hanagata1, Wolfgang Schmitt3 and Toshiyuki Ikoma1,*

1 Biomaterials Center, National Institute for Materials Science, 1-2-1 Sengen, Tsukuba, Ibaraki, 305-0047, Japan
2 Advanced Nano-Characterization Center, National Institute for Materials Science, 3-13 Sakura, Tsukuba, Ibaraki, 305-0003, Japan
3 School of Chemistry, Trinity College Dublin, Dublin 2, Ireland
4 International Center for Young Scientists, National Institute for Materials Science, 1-2-1 Sengen, Tsukuba, Ibaraki, 305-0047, Japan

* To whom correspondence should be addressed. E-mail: IKOMA.Toshiyuki{at}nims.go.jp

Magnetic nanoparticle (MNP) composites with a magnetite (Fe3O4) core and a hydroxyapatite (HAp, Ca10(PO4)6(OH)2) coating were prepared using a precipitation method and a subsequent hydrothermal treatment. The hydrothermal treatment diminished the lepidocrocite layer on the magnetite, enhanced the crystal growth of HAp and dissolved the MNPs. The divalent iron ions dissolved into solvent were not substituted for the HAp lattice. The three-dimensional (3D) nanostructure, the crystal morphology of HAp covered with the MNPs and the interfacial nanostructure of magnetite/HAp were analyzed using an energy-filter transmission electron microscopy (EF-TEM) and visualized by computer tomography in transmission electron microscopy (TEM). EF-TEM and 3D reconstruction images using a tilted series of high-angle annular dark-field images showed that the needlelike HAp nanocrystals covered with a magnetite core and the crystal growth of HAp attached to the magnetite surface was inhibited as a result of the lower density of the nucleation site of the lepidocrocite layer. The dissolution of iron ion from MNPs and the interfacial interaction of HAp and magnetite could cause the needlelike morphology of HAp nanocrystals.

Keywords     electron tomography, magnetite, hydroxyapatite, magnetic nanoparticle, hyperthermia, MRI

Received     27 August 2009, accepted 29 September 2009


Add to CiteULike CiteULike   Add to Connotea Connotea   Add to Del.icio.us Del.icio.us    What's this?




Disclaimer: Please note that abstracts for content published before 1996 were created through digital scanning and may therefore not exactly replicate the text of the original print issues. All efforts have been made to ensure accuracy, but the Publisher will not be held responsible for any remaining inaccuracies. If you require any further clarification, please contact our Customer Services Department.