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Synthesis of phase-pure and monodisperse iron oxide nanoparticles by thermal decomposition
Open accessAbstract
Superparamagnetic iron oxide nanoparticles (SPIONs) are used for a wide range of biomedical applications requiring precise control over their physical and magnetic properties, which are dependent on their size and crystallographic phase. Here we present a comprehensive template for the design and synthesis of iron oxide nanoparticles with control over size, size distribution, phase, and resulting magnetic properties. We investigate critical parameters for synthesis of monodisperse SPIONs by organic thermal decomposition. Three different, commonly used, iron containing precursors (iron oleate, iron pentacarbonyl, and iron oxyhydroxide) are evaluated under a variety of synthetic conditions. We compare the suitability of these three kinetically controlled synthesis protocols, which have in common the use of iron oleate as a starting precursor or reaction intermediate, for producing nanoparticles with specific size and magnetic properties. Monodisperse particles were produced over a tunable range of sizes from approximately 2-30 nm. Reaction parameters such as precursor concentration, addition of surfactant, temperature, ramp rate, and time were adjusted to kinetically control size and size-distribution, phase, and magnetic properties. In particular, large quantities of excess surfactant (up to 25 : 1 molar ratio) alter reaction kinetics and result in larger particles with uniform size; however, there is often a trade-off between large particles and a narrow size distribution. Iron oxide phase, in addition to nanoparticle size and shape, is critical for establishing magnetic properties such as differential susceptibility (dm/dH) and anisotropy. As an example, we show the importance of obtaining the required size and iron oxide phase for application to Magnetic Particle Imaging (MPI), and describe how phase purity can be controlled. These results provide much of the information necessary to determine which iron oxide synthesis protocol is best suited to a particular application.
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“SPION with high control over size and shape, narrow size distribution and good crystallinity can be prepared via thermal decomposition of organoiron precursors in high-boiling point organic solvents in the presence of stabilizing surfactants [38, 39].”
From Iron oxide nanoparticles: Diagnostic, therapeutic and theranostic applications (2019) · cites this paper as [39]
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Metadata
- Authors
- Hufschmid, R., Arami, H., Ferguson, R. M., Gonzales, M., Teeman, E., Brush, L. N., Browning, N. D., & Krishnan, K. M.
- Affiliations
- University of Washington (US)
- Pacific Northwest National Laboratory (US)
- Corresponding author
- Krishnan, Kannan M.
- ORCID
- Venue
- Nanoscale
- Publisher
- Royal Society of Chemistry (RSC)
- Published
- 2015
- Volume
- 7
- Issue
- 25
- Pages
- 11142-11154
- ISSN
- 2040-3364 (ISSN-L)
- 2040-3372
- PMC
- PMC5198837
- OpenAlex
- W1810290940
- Cited by
- 341
- References
- 71
- Citations by year
- 2026: 20 · 2025: 31 · 2024: 28 · 2023: 31 · 2022: 31 · 2021: 49 · 2020: 33 · 2019: 39 · 2018: 28 · 2017: 24 · 2016: 19 · 2015: 7
- FWCI
- 12.93
- Type
- journal article
- Language
- en
- Open access
- green
- www.ncbi.nlm.nih.gov
- Locations
- Nanoscale (publishedVersion)
- PubMed (publishedVersion)
- PubMed Central (acceptedVersion)
- Funders
- National Institutes of Health (1R41EB013520-01, 1R42EB013520-01, 1RO1EB013689-01/NIBIB)
- Advanced Research Projects Agency - Energy (DE-AC05-76RL01830)
- Topics
- Physical Sciences › Engineering › Biomedical Engineering › Characterization and Applications of Magnetic Nanoparticles
- Physical Sciences › Materials Science › Materials Chemistry › Magnetic Properties and Synthesis of Ferrites
- Physical Sciences › Earth and Planetary Sciences › Geophysics › Geomagnetism and Paleomagnetism Studies
- Keywords
- superparamagnetic iron oxide nanoparticles, thermal decomposition, monodisperse nanoparticles, phase purity, iron oleate, iron pentacarbonyl, iron oxyhydroxide, particle size control, size distribution, magnetic properties, magnetic anisotropy, differential susceptibility, magnetic particle imaging
- MeSH terms
- Ferric Compounds, Hot Temperature, Particle Size, Spectrum Analysis, Raman, Oleic Acid, Nanotechnology, Iron Compounds, Magnetite Nanoparticles
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