Article

Controlled synthesis of iron oxide nanoparticles over a wide size range.

Departament de Física Fonamental and Institut de Nanociència i Nanotecnologia, Universitat de Barcelona, 08028 Barcelona, Catalonia, Spain.
Langmuir (impact factor: 4.19). 12/2009; 26(8):5843-7. DOI:10.1021/la903767e pp.5843-7
Source: PubMed

ABSTRACT We report on the effect of using decanoic acid as capping ligand on the synthesis of iron oxide nanoparticles by thermal decomposition of an organic iron precursor in organic medium. This procedure allowed us to control the particle size within 5 nm and about 30 nm by modifying the precursor-to-capping ligand ratio in a systematic fashion and to further expand the particle size range up to about 50 nm by adjusting the final synthesis temperature. The nanoparticles also showed high saturation magnetization of about 80-83 emu/g at low temperature, almost size-independent and close to the value for the bulk counterpart. Decanoic acid-coated nanoparticles were transferred to water by using tetramethylammonium hydroxide, which allowed further coating with silica in a tetraethyl orthosilicate solution. Consequently, these iron oxide nanoparticles are tunable in size and highly magnetic, and they could become suitable candidates for various biomedical applications such as contrast agents for magnetic resonance imaging and magnetic carriers for drug delivery.

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    Article: Biodegradation of Iron Oxide Nanocubes: High Resolution In Situ Monitoring.
    Lenaic Lartigue, Damien Alloyeau, Jelena Kolosnjaj-Tabi, Yasir Javed, Pablo Guardia, Andreas Riedinger, Christine Pechoux, Teresa Pellegrino, Claire Wilhelm, Florence Gazeau
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Keywords

coating
 
decanoic acid
 
Decanoic acid-coated nanoparticles
 
final synthesis temperature
 
iron oxide nanoparticles
 
magnetic
 
magnetic carriers
 
magnetic resonance imaging
 
particle size
 
particle size range
 
saturation magnetization
 
size-independent
 
suitable candidates
 
systematic fashion
 
tetraethyl orthosilicate solution
 
tetramethylammonium hydroxide
 
various biomedical applications
 

Pablo Guardia