Synthesis, Characterization, and Nanocatalysis Application of Core–Shell Superparamagnetic Nanoparticles of Fe3O4@Pd

There is a wide number of different synthetic methods to obtain magnetite (Fe3O4) superparamagnetic nanoparticles (SPNPs). However, only a few are able to produce very small and well defined SPNPs with narrow size distribution. We report a modification of the metal-complex decomposition in organic media method in which we replace iron(iii) acetylacetonate (Fe(Acac)3) with an iron–urea complex (Fe-Urea) as metal source for the synthesis. With this modification we were able to obtain small particle sizes with a good control in size distribution. The Fe-Urea complex is easy to prepare with excellent yields. Core–shell nanoparticles are then prepared using palladium(ii) acetylacetonate as a Pd source, to obtain a Pd0 shell stabilised by oleylamine. The core–shell superparamagnetic nanoparticles of Fe3O4@Pd-OA are extensively characterized by FT-IR, powder X-ray diffraction, transmission electron microscopy, UV-vis, thermogravimetric analysis/differential scanning calorimetry, and magnetic susceptibility measurements, and tested in a palladium-catalyzed cross-coupling Suzuki–Miyaura reaction with promising results.

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The Preparation and Characteristic of Superparamagnetic Core/Shell Nanoparticles

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.274.432 ◽

2013 ◽

Vol 274 ◽

pp. 432-435

Author(s):

Hong Xia Shen ◽

Zheng Zhi Yin ◽

Qiong Cheng

Keyword(s):

Biomedical Applications ◽

Superparamagnetic Nanoparticles ◽

Bioactive Molecules ◽

Core Shell ◽

Shell Nanoparticles ◽

X Ray ◽

Transmission Electron ◽

Vibration Sample Magnetometer ◽

Diffraction Patterns ◽

Core Shell Nanoparticles

Superparamagnetic core/shell nanoparticles have been prepared successfully by the reduction of Au3+ onto the surface of superparamagnetic nanoparticles. The core/shell nanoparticles were characterized by Transmission electron microscopy (TEM), X-ray powder diffraction patterns (XRD), UV–vis spectrophotometer, Vibration Sample Magnetometer(VSM) and micro-confocal Raman system. The results revealed that the prepared core/shell nanoparticles were covered by Au shell. These superparamagnetic nanoparticles can be highly sensitively detected and afford new opportunities for biomedical applications through chemical bonding of bioactive molecules with the Au shell of nanoparticles.

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Characterization of multifunctional β-NaEuF4/NaGdF4 core–shell nanoparticles with narrow size distribution

Nanoscale ◽

10.1039/c5nr06915g ◽

2016 ◽

Vol 8 (5) ◽

pp. 2832-2843 ◽

Cited By ~ 10

Author(s):

Lilli Schneider ◽

Thorben Rinkel ◽

Benjamin Voß ◽

Artur Chrobak ◽

Johann P. Klare ◽

...

Keyword(s):

Size Distribution ◽

Core Shell ◽

Narrow Size Distribution ◽

Shell Nanoparticles ◽

Core Shell Nanoparticles

We characterized NaEuF4/NaGdF4 core–shell nanoparticles.

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Controllable Engineering and Functionalizing Nanoparticles with Specific Targeting Capability

10.21203/rs.3.rs-155967/v1 ◽

2021 ◽

Author(s):

Zhanchen Guo ◽

Rongrong Xing ◽

Zhen Liu

Keyword(s):

Breast Cancer ◽

Biomedical Applications ◽

High Specificity ◽

Superparamagnetic Nanoparticles ◽

Breast Cancer Cell Lines ◽

Core Shell ◽

Shell Nanoparticles ◽

Specific Targeting ◽

Dual Functional ◽

Core Shell Nanoparticles

Abstract Due to unique properties, nanoparticles been widely used in important biomedical applications such as imaging, drug delivery and disease therapy. Targeting toward specific proteins is essential for the effective utilization of nanoparticles. However, current targeting strategies mainly rely on surface modification with bio-ligands, which often not only fail to provide desired properties but also remain challenging. Here we report an unprecedented approach, called reverse microemulsion-confined epitope-oriented surface imprinting and cladding (ROSIC), for facile, versatile and controllable engineering coreless and core/shell nanoparticles with tunable monodispersed size as well as specific targeting capability towards proteins and peptides. Via engineering coreless imprinted and cladded silica nanoparticles, the effectiveness and superiority over conventional imprinting of the proposed approach was first verified. The prepared nanoparticles exhibited both high specificity and high affinity. Using quantum dots (QDs), superparamagnetic nanoparticles, silver nanoparticles and upconverting nanoparticles as a representative set of core substrates, a variety of dual-functional single-core/shell nanoparticles were then successfully prepared. Finally, selective fluorescence imaging of triple negative breast cancer cells over other breast cancer cell lines using QD-cored nanoparticles was achieved, which well demonstrated the potential of the prepared core/shell nanoparticles in biomedical applications. Thus, this approach opened a new avenue to engineering and functionalization of advanced nanoparticles with targeting capability, holding great prospects in biomedical applications.

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Effect of Magnetic and Geometric Properties on the Time of Magnetic Relaxation of Superparamagnetic Core-Shell Nanoparticles

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.821-822.1336 ◽

2013 ◽

Vol 821-822 ◽

pp. 1336-1340

Author(s):

Leonid L. Afremov ◽

Ilia Ilyushin

Keyword(s):

Relaxation Time ◽

Magnetic Relaxation ◽

Superparamagnetic Nanoparticles ◽

Exchange Constant ◽

Core Shell ◽

Shell Nanoparticles ◽

Interphase Interaction ◽

Geometric Properties ◽

Core Shell Nanoparticles ◽

Magnetic States

Within the frame of two-phase superparamagnetic nanoparticles the effect of magnetic and geometric properties of superparamagnetic nanoparicles on the time of their magnetic relaxation has been defined. With increasing of volume, elongation of nanoparticle and relative volume of inclusions the time of relaxation grows rapidly. Metastability conditions of magnetic states have been developed. Growth of exchange constant magnitude of interphase interaction results in increasing of relaxation time regardless of exchange constant sign. Keywords: superparamagnetic particles, core-shell nanoparticles, relaxation time, magnetic states, critical field, metastable magnetic states, interphase exchange interaction.

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