scholarly journals Signature of antiphase boundaries in iron oxide nanoparticles

2021 ◽  
Vol 54 (6) ◽  
Author(s):  
Tobias Köhler ◽  
Artem Feoktystov ◽  
Oleg Petracic ◽  
Nileena Nandakumaran ◽  
Antonio Cervellino ◽  
...  
Keyword(s):  
Iron Oxide ◽  
Iron Oxide Nanoparticles ◽  
Powder Diffraction ◽  
Magnetic Moments ◽  
Reference Value ◽  
Oxide Nanoparticles ◽  
Planar Lattice ◽  
Antiphase Boundaries ◽  
Diffraction Patterns ◽  
The Fourier Transform

Iron oxide nanoparticles find a wide variety of applications, including targeted drug delivery and hyperthermia in advanced cancer treatment methods. An important property of these particles is their maximum net magnetization, which has been repeatedly reported to be drastically lower than the bulk reference value. Previous studies have shown that planar lattice defects known as antiphase boundaries (APBs) have an important influence on the particle magnetization. The influence of APBs on the atomic spin structure of nanoparticles with the γ-Fe2O3 composition is examined via Monte Carlo simulations, explicitly considering dipole–dipole interactions between the magnetic moments that have previously only been approximated. For a single APB passing through the particle centre, a reduction in the magnetization of 3.9% (for 9 nm particles) to 7.9% (for 5 nm particles) is found in saturation fields of 1.5 T compared with a particle without this defect. Additionally, on the basis of Debye scattering equation simulations, the influence of APBs on X-ray powder diffraction patterns is shown. The Fourier transform of the APB peak profile is developed to be used in a whole powder pattern modelling approach to determine the presence of APBs and quantify them by fits to powder diffraction patterns. This is demonstrated on experimental data, where it could be shown that the number of APBs is related to the observed reduction in magnetization.

Adsorptive removal of V(V) ions using clinoptilolite modified with polypyrrole and iron oxide nanoparticles in column studies

MRS Advances ◽  
2018 ◽  
Vol 3 (36) ◽  
pp. 2119-2127 ◽  
Author(s):  
NOMCEBO H. MTHOMBENI ◽  
SANDRINE MBAKOP ◽  
AOYI OCHIENG ◽  
MAURICE S. ONYANGO
Keyword(s):  
Electron Microscope ◽  
Iron Oxide ◽  
Iron Oxide Nanoparticles ◽  
Metal Ion ◽  
Fixed Bed ◽  
Breakthrough Curves ◽  
Ion Concentration ◽  
Oxide Nanoparticles ◽  
Column Studies ◽  
The Fourier Transform

AbstractClinoptilolite modified with polypyrrole and iron oxide nanoparticles (Cln-PPy-Fe3O4) nanocomposite as a potential adsorbent for V (V) ions was prepared via polymerization of pyrrole monomer using FeCl3 oxidant in aqueous medium in which clinoptilolite-Fe3O4 nanoparticles were suspended. The structure and morphology of the prepared adsorbent was analysed with the Fourier transform infrared (FTIR) spectrometer, field-emission scanning electron microscope (FE-SEM), energy dispersive X-ray spectroscopy (EDX) and high-resolution transmission electron microscope (HR-TEM). Column fixed bed studies were performed to test the ability of the adsorbent to remove V (V) ions from aqueous solution. Low values of adsorbent exhaustion rate (AER) and large bed volumes were observed at lower metal ion concentration, higher bed mass and lower flow rate for V(V) removal indicating good performance. The volume of treated water processed at breakthrough point were found to be 0.09; 0.63 and 1.26 L for bed mass of 1, 2.5; and 5 g, respectively. The Yoon–Nelson and Thomas models appropriately described the breakthrough curves.

scholarly journals Imaging Constructs: The Rise of Iron Oxide Nanoparticles

Molecules ◽  
2021 ◽  
Vol 26 (11) ◽  
pp. 3437
Author(s):  
Bianca Elena-Beatrice Crețu ◽  
Gianina Dodi ◽  
Amin Shavandi ◽  
Ioannis Gardikiotis ◽  
Ionela Lăcrămioara Șerban ◽  
...  
Keyword(s):  
Iron Oxide ◽  
Iron Oxide Nanoparticles ◽  
Magnetic Moments ◽  
Quantitative Imaging ◽  
Oxide Nanoparticles ◽  
Imaging Probes ◽  
Effective System ◽  
Important Challenge ◽  
Metal Oxide Nanomaterials ◽  
Clinical Potential

Over the last decade, an important challenge in nanomedicine imaging has been the work to design multifunctional agents that can be detected by single and/or multimodal techniques. Among the broad spectrum of nanoscale materials being investigated for imaging use, iron oxide nanoparticles have gained significant attention due to their intrinsic magnetic properties, low toxicity, large magnetic moments, superparamagnetic behaviour and large surface area—the latter being a particular advantage in its conjunction with specific moieties, dye molecules, and imaging probes. Tracers-based nanoparticles are promising candidates, since they combine synergistic advantages for non-invasive, highly sensitive, high-resolution, and quantitative imaging on different modalities. This study represents an overview of current advancements in magnetic materials with clinical potential that will hopefully provide an effective system for diagnosis in the near future. Further exploration is still needed to reveal their potential as promising candidates from simple functionalization of metal oxide nanomaterials up to medical imaging.

Preparation of Iron Oxide Nanoparticles by a Pyrosol Technique

2007 ◽  
Vol 353-358 ◽  
pp. 2175-2178 ◽  
Author(s):  
W. Thongsuwan ◽  
Aukkaravittayapun Suparerk ◽  
Pisith Singjai
Keyword(s):  
Iron Oxide ◽  
Iron Oxide Nanoparticles ◽  
Nitrate Solution ◽  
Precursor Solution ◽  
Oxide Nanoparticles ◽  
X Ray Diffraction ◽  
Air Stream ◽  
Diffraction Patterns ◽  
Microscopy Images ◽  
Good Agreement

Iron oxide nanoparticles were prepared from an iron nitrate solution by a pyrosol technique. The precursor solution was atomized by a mist generator in order to form an aerosol which was brought into a tube furnace by a controlled flowing air stream. The pyrolysis of the aerosol was occurred to form the particles inside the furnace at 350 °C. Scanning electron microscopy images have shown that a mean diameter of the particles is in good agreement with the third root of the precursor concentration. X-ray diffraction patterns have revealed that the main peaks from the samples are corresponding to the α-Fe2O3 phase.

scholarly journals Mechanism of magnetization reduction in iron oxide nanoparticles

Nanoscale ◽  
2021 ◽  
Vol 13 (14) ◽  
pp. 6965-6976
Author(s):  
Tobias Köhler ◽  
Artem Feoktystov ◽  
Oleg Petracic ◽  
Emmanuel Kentzinger ◽  
Tanvi Bhatnagar-Schöffmann ◽  
...  
Keyword(s):  
Oleic Acid ◽  
Iron Oxide ◽  
Saturation Magnetization ◽  
Iron Oxide Nanoparticles ◽  
Oxide Nanoparticles ◽  
Major Contributor ◽  
Antiphase Boundaries ◽  
Acid Coating

Antiphase boundaries in iron oxide nanoparticles with oleic acid coating were found to be a major contributor to the observed reduction in saturation magnetization.

scholarly journals Analysis of Organochlorine Pesticides in Drinking Water and their Degradation by Synthesized Iron oxide Nanoparticles

2020 ◽  
Vol 32 (5) ◽  
pp. 1177-1182
Author(s):  
Bharti ◽  
J.S. Jangwan ◽  
Amrish Kumar ◽  
Vivek Kumar
Keyword(s):  
Drinking Water ◽  
Iron Oxide ◽  
Organochlorine Pesticides ◽  
Iron Oxide Nanoparticles ◽  
Precipitation Method ◽  
Oxide Nanoparticles ◽  
X Ray Diffraction ◽  
Detection Analysis ◽  
Diffraction Patterns ◽  
Co Precipitation

This study reports the analysis of drinking water sources of river Krishni catchment, contaminated by organochlorine pesticides. Iron oxide nanoparticles had been synthesized through co-precipitation method and utilized for the degradation of organochlorine pesticides using advanced oxidation processes. The sharp and narrow peaks of X-ray diffraction patterns revealed the crystalline nature of synthesized iron oxide nanoparticles having size less than 100 nm. The nanoparticles were also characterized using TEM, UV-Vis and IR spectral analysis. Liquid-liquid extraction and GC-MS were used for the detection analysis of pesticides. GC-MS technique was used for further quantitative analysis of 19 pesticides. The degradation analysis showed the maximum amount of degradation (up to 98.38 %) of organochlorine pesticides.

TARGETING CYCLIN B1 WITH ANTISENSE OLIGONUCLETOTIDES- COATED SUPERPARAMAGNETIC IRON OXIDE NANOPARTICLES

2018 ◽  
Vol 6 (10) ◽  
Author(s):  
Hosam Zaghloul ◽  
Doaa A. Shahin ◽  
Ibrahim El- Dosoky ◽  
Mahmoud E. El-awady ◽  
Fardous F. El-Senduny ◽  
...  
Keyword(s):  
Iron Oxide ◽  
Iron Oxide Nanoparticles ◽  
Cellular Uptake ◽  
Superparamagnetic Iron Oxide ◽  
Cyclin B1 ◽  
Superparamagnetic Iron Oxide Nanoparticles ◽  
Oxide Nanoparticles ◽  
Mcf7 Cells ◽  
M Phase ◽  
The Impact

Antisense oligonucleotides (ASO) represent an attractive trend as specific targeting molecules but sustain poor cellular uptake meanwhile superparamagnetic iron oxide nanoparticles (SPIONs) offer stability of ASO and improved cellular uptake. In the present work we aimed to functionalize SPIONs with ASO targeting the mRNA of Cyclin B1 which represents a potential cancer target and to explore its anticancer activity. For that purpose, four different SPIONs-ASO conjugates, S-M (1–4), were designated depending on the sequence of ASO and constructed by crosslinking carboxylated SPIONs to amino labeled ASO. The impact of S-M (1–4) on the level of Cyclin B1, cell cycle, ROS and viability of the cells were assessed by flowcytometry. The results showed that S-M3 and S-M4 reduced the level of Cyclin B1 by 35 and 36%, respectively. As a consequence to downregulation of Cyclin B1, MCF7 cells were shown to be arrested at G2/M phase (60.7%). S-M (1–4) led to the induction of ROS formation in comparison to the untreated control cells. Furthermore, S-M (1–4) resulted in an increase in dead cells compared to the untreated cells and SPIONs-treated cells. In conclusion, targeting Cyclin B1 with ASO-coated SPIONs may represent a specific biocompatible anticancer strategy.

Ferrozine Assay for Simple and Cheap Iron Analysis of Silica-Coated Iron Oxide Nanoparticles

2018 ◽  
Author(s):  
Hattie Ring ◽  
Zhe Gao ◽  
Nathan D. Klein ◽  
Michael Garwood ◽  
John C. Bischof ◽  
...  
Keyword(s):  
Iron Oxide ◽  
Iron Oxide Nanoparticles ◽  
Hydrofluoric Acid ◽  
Inductively Coupled Plasma ◽  
Silica Shell ◽  
Oxide Nanoparticles ◽  
Inductively Coupled ◽  
Digestion Process ◽  
Plasma Methods ◽  
Iron Analysis

The Ferrozinen assay is applied as an accurate and rapid method to quantify the iron content of iron oxide nanoparticles (IONPs) and can be used in biological matrices. The addition of ascorbic aqcid accelerates the digestion process and can penetrate an IONP core within a mesoporous and solid silica shell. This new digestion protocol avoids the need for hydrofluoric acid to digest the surrounding silica shell and provides and accessible alternative to inductively coupled plasma methods. With the updated digestion protocol, the quantitative range of the Ferrozine assay is 1 - 14 ppm. <br>

Ferrozine Assay for Simple and Cheap Iron Analysis of Silica-Coated Iron Oxide Nanoparticles

2018 ◽  
Author(s):  
Hattie Ring ◽  
Zhe Gao ◽  
Nathan D. Klein ◽  
Michael Garwood ◽  
John C. Bischof ◽  
...  
Keyword(s):  
Iron Oxide ◽  
Iron Oxide Nanoparticles ◽  
Hydrofluoric Acid ◽  
Inductively Coupled Plasma ◽  
Silica Shell ◽  
Oxide Nanoparticles ◽  
Inductively Coupled ◽  
Digestion Process ◽  
Plasma Methods ◽  
Iron Analysis

The Ferrozinen assay is applied as an accurate and rapid method to quantify the iron content of iron oxide nanoparticles (IONPs) and can be used in biological matrices. The addition of ascorbic aqcid accelerates the digestion process and can penetrate an IONP core within a mesoporous and solid silica shell. This new digestion protocol avoids the need for hydrofluoric acid to digest the surrounding silica shell and provides and accessible alternative to inductively coupled plasma methods. With the updated digestion protocol, the quantitative range of the Ferrozine assay is 1 - 14 ppm. <br>

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