Nontoxic nanoparticle contrast agents with multiple imaging functions are required for medical diagnostic imaging, and coating the less toxic materials meets this requirement. This work proposes a method fabricating magnetite, gold (Au), silica nanoparticles toward imaging. The proposed involved four steps: synthesis of magnetite (Fe3O4) nanoparticles, Au formation composite Fe3O4 (Fe3O4/Au), F...

The iron oxide mineral magnetite (Fe3O4) is produced by various organisms to exploit magnetic and mechanical properties. Magnetotactic bacteria have become one of the best model organisms for studying magnetite biomineralization, as their genomes are sequenced and tools are available for their genetic manipulation. However, the chemical route by which magnetite is formed intracellularly within ...

in this research controlled coating of magnetite (fe3o4) nanoparticles with sio2 was investigated. the fe3o4 nanoparticles were synthesized via chemical co-precipitation and then coated by silica according to stober method. effects of tetra ethyl ortho silicate (teos) concentration and ethanol to teos on the coating thickness were investigated. x-ray powder diffraction, fourier transform infrar...

Cinnamomum verum-functionalized Fe3O4 nanoparticles of 9.4 nm in size were laser transferred by matrix assisted pulsed laser evaporation (MAPLE) technique onto gastrostomy tubes (G-tubes) for antibacterial activity evaluation toward Gram positive and Gram negative microbial colonization. X-ray diffraction analysis of the nanoparticle powder showed a polycrystalline magnetite structure, whereas ...

This paper reports a type of multifunctional hybrid nanoparticle (NP) composed of gold nanocrystals coated on and/or embedded in a magnetite-fluorescent porous carbon core-shell NP template (Fe3O4@PC-CDs-Au) for biomedical applications, including magnetic/NIR-responsive drug release, multicolor cell imaging, and enhanced photothermal therapy. The synthesis of the Fe3O4@PC-CDs-Au NPs firstly inv...

This study aims at exploring an effective route in the in situ graft polymerization of aniline from Fe3O4 nanoparticles. To this goal, Fe3O4 magnetic nanoparticles were prepared by coprecipitation method using ammonia solution as the precipitating agent, and were characterized by Fourier transform infrared (FT-IR) spectroscopy, X-ray diffraction (XRD) and transmission electron microscopy (TEM)....

The thermal demagnetization of pseudo-single-domain (PSD) magnetite (Fe3O4) particles, which govern the magnetic signal in many igneous rocks, is examined using off-axis electron holography. Visualization of a vortex structure held by an individual Fe3O4 particle (~250 nm in diameter) during in situ heating is achieved through the construction and examination of magnetic-induction maps. Stepwis...

Greigite (Fe3S4) and its analogue oxide, magnetite (Fe3O4), are natural minerals with an inverse spinel structure whose atomic-level properties may be difficult to investigate experimentally. Here, [D. Rickard and G. W. Luther, Chem. Rev. 107, 514 (2007)] we have calculated the elastic constants and other macroscopic mechanical properties by applying elastic strains on the unit cells. We also h...

Half-metallic materials, such as CrO2, La0.7Sr0.3MnO3 (LSMO), and Fe3O4 are highly attractive for spintronics applications because of their high spin polarization. Among these materials, magnetite (Fe3O4) is superior to others because of its high Curie temperature (Tc) of 858 K, which is crucial for thermal stability in device applications. In addition, magnetite has proven to be a ferromagneti...

Magnetite (Fe3O4) is an important magnetic mineral to Earth scientists, as it carries the dominant magnetic signature in rocks, and the understanding of its magnetic recording fidelity provides a critical tool in the field of palaeomagnetism. However, reliable interpretation of the recording fidelity of Fe3O4 particles is greatly diminished over time by progressive oxidation to less magnetic ir...