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Complete Exchange of the Hydrophobic Dispersant Shell on Monodisperse Superparamagnetic Iron Oxide Nanoparticles.

Bixner O, Lassenberger A, Baurecht D, Reimhult E - Langmuir (2015)

Bottom Line: Most applications require a stable presentation of a defined surface chemistry; therefore, the native shell has to be completely exchanged for dispersants with irreversible affinity to the nanoparticle surface.A mechanism and multiple exchange scheme that attains the goal of complete and irreversible ligand replacement on monodisperse nanoparticles of various sizes is presented.The obtained hydrophobic nanoparticles are ideally suited for magnetically controlled drug delivery and membrane applications and for the investigation of fundamental interfacial properties of ultrasmall core-shell architectures.

View Article: PubMed Central - PubMed

Affiliation: Department of Nanobiotechnology, Institute for Biologically Inspired Materials, University of Natural Resources and Life Sciences Vienna , Muthgasse 11, 1190 Vienna, Austria.

ABSTRACT
High-temperature synthesized monodisperse superparamagnetic iron oxide nanoparticles are obtained with a strongly bound ligand shell of oleic acid and its decomposition products. Most applications require a stable presentation of a defined surface chemistry; therefore, the native shell has to be completely exchanged for dispersants with irreversible affinity to the nanoparticle surface. We evaluate by attenuated total reflectance-Fourier transform infrared spectroscopy (ATR-FTIR) and thermogravimetric analysis/differential scanning calorimetry (TGA/DSC) the limitations of commonly used approaches. A mechanism and multiple exchange scheme that attains the goal of complete and irreversible ligand replacement on monodisperse nanoparticles of various sizes is presented. The obtained hydrophobic nanoparticles are ideally suited for magnetically controlled drug delivery and membrane applications and for the investigation of fundamental interfacial properties of ultrasmall core-shell architectures.

No MeSH data available.


TEM of spherical, monodisperse magnetite nanoparticleswith narrowsize distributions of (a) 3.5 ± 0.4 nm, (b) 5.0 ± 0.4 nm,and (c) 8.3 ± 0.4 nm and (d) high-resolution (HR)-TEM of the8.3 ± 0.4 nm SPIONs in panel c.
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fig1: TEM of spherical, monodisperse magnetite nanoparticleswith narrowsize distributions of (a) 3.5 ± 0.4 nm, (b) 5.0 ± 0.4 nm,and (c) 8.3 ± 0.4 nm and (d) high-resolution (HR)-TEM of the8.3 ± 0.4 nm SPIONs in panel c.

Mentions: Figure 1 shows TEMmicrographs of the as-synthesized, OA-capped magnetite nanoparticleswith narrow size distributions of 3.5 ± 0.4, 5.0 ± 0.4,and 8.3 ± 0.4 nm.


Complete Exchange of the Hydrophobic Dispersant Shell on Monodisperse Superparamagnetic Iron Oxide Nanoparticles.

Bixner O, Lassenberger A, Baurecht D, Reimhult E - Langmuir (2015)

TEM of spherical, monodisperse magnetite nanoparticleswith narrowsize distributions of (a) 3.5 ± 0.4 nm, (b) 5.0 ± 0.4 nm,and (c) 8.3 ± 0.4 nm and (d) high-resolution (HR)-TEM of the8.3 ± 0.4 nm SPIONs in panel c.
© Copyright Policy
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4554299&req=5

fig1: TEM of spherical, monodisperse magnetite nanoparticleswith narrowsize distributions of (a) 3.5 ± 0.4 nm, (b) 5.0 ± 0.4 nm,and (c) 8.3 ± 0.4 nm and (d) high-resolution (HR)-TEM of the8.3 ± 0.4 nm SPIONs in panel c.
Mentions: Figure 1 shows TEMmicrographs of the as-synthesized, OA-capped magnetite nanoparticleswith narrow size distributions of 3.5 ± 0.4, 5.0 ± 0.4,and 8.3 ± 0.4 nm.

Bottom Line: Most applications require a stable presentation of a defined surface chemistry; therefore, the native shell has to be completely exchanged for dispersants with irreversible affinity to the nanoparticle surface.A mechanism and multiple exchange scheme that attains the goal of complete and irreversible ligand replacement on monodisperse nanoparticles of various sizes is presented.The obtained hydrophobic nanoparticles are ideally suited for magnetically controlled drug delivery and membrane applications and for the investigation of fundamental interfacial properties of ultrasmall core-shell architectures.

View Article: PubMed Central - PubMed

Affiliation: Department of Nanobiotechnology, Institute for Biologically Inspired Materials, University of Natural Resources and Life Sciences Vienna , Muthgasse 11, 1190 Vienna, Austria.

ABSTRACT
High-temperature synthesized monodisperse superparamagnetic iron oxide nanoparticles are obtained with a strongly bound ligand shell of oleic acid and its decomposition products. Most applications require a stable presentation of a defined surface chemistry; therefore, the native shell has to be completely exchanged for dispersants with irreversible affinity to the nanoparticle surface. We evaluate by attenuated total reflectance-Fourier transform infrared spectroscopy (ATR-FTIR) and thermogravimetric analysis/differential scanning calorimetry (TGA/DSC) the limitations of commonly used approaches. A mechanism and multiple exchange scheme that attains the goal of complete and irreversible ligand replacement on monodisperse nanoparticles of various sizes is presented. The obtained hydrophobic nanoparticles are ideally suited for magnetically controlled drug delivery and membrane applications and for the investigation of fundamental interfacial properties of ultrasmall core-shell architectures.

No MeSH data available.