Formation and migration of magnetic particles associated with iron oxide transformation at a hillslope scale

CATENA ◽  
2021 ◽  
Vol 197 ◽  
pp. 104944
Author(s):  
Shanglong Guo ◽  
Yunfeng Cai ◽  
Juan Ren ◽  
Yanxia Guan ◽  
Dengchun Xin ◽  
...  
2018 ◽  
Vol 135 (44) ◽  
pp. 46869
Author(s):  
Shan Li ◽  
Zhaoqi Zhu ◽  
Zhilong Hu ◽  
Hanxue Sun ◽  
Peng Mu ◽  
...  

Author(s):  
Leila Sadeghi ◽  
◽  
Arezu Marefat ◽  

Introduction: Iron oxide nanoparticles (Fe2O3-NPs) are small magnetic particles that widely used in different aspects of biology and medicine in modern life. Fe2O3-NP accumulated in the living cells due to absence of active system to excrete the iron ions so damages cellular organelles by highly reactivity. Method: Herein cytotoxic effects of Fe2O3-NP with 50 nm size were investigated on primary culture of neonatal rat hippocampus by MTT assay. Pathophysiological signs of Alzheimer disease such as amyloid precursor protein (APP) expression, Aβ aggregation, soluble APPα and APPβ secretion also were investigated in hippocampal cells treated by various concentration of NP for different exposure time. Results: Our results revealed, Fe2O3-NP treatment causes oxidative stress in cells that accompanied by upregulation of the APP and Aβ in a concentration dependent manner. NP exposing also leads to more secretion of sAPPβ rather than sAPPα that concluded to increased activation of β-secretase in NP received cells. All of the harmful effects accumulate in neurons that could not be renovated so lead to neurodegeneration in Alzheimer disease. Conclusion: This study approved iron-based NPs could help to develop the Alzheimer and related neurological disorders and explained why some of the iron chelators have therapeutic potential in Alzheimer disease.


Polymers ◽  
2019 ◽  
Vol 11 (9) ◽  
pp. 1430
Author(s):  
Shu-Chian Yang ◽  
Chun-Yu Chen ◽  
Hung-Yu Wan ◽  
Szu-Ying Huang ◽  
Ta-I Yang

Cancer has been one of the leading causes of human death for centuries. Magnetic hyperthermia is a promising technique to confine and control cancers. However, particles used in magnetic hyperthermia leaking from where the cancers are located could compromise human health. Therefore, we developed electroactive iron oxide/block copolymer composites to tackle the leakage problem. Experimental results show that oleylamine-modified magnetic iron oxide (Fe3O4) particles and electroactive tetraaniline (TA) could be templated in the self-assembled microstructures of sulfonated [styrene-b-(ethylene-ran-butylene)-b-styrene] (S-SEBS) block copolymers. Various amounts of Fe3O4 particles and TA oligomer were incorporated in S-SEBS block copolymer and their electroactive behavior was confirmed by exhibiting two pairs of well-defined anodic and cathodic current peaks in cyclic voltammetry tests. The heating performance of the resultant TA/Fe3O4/polymer composites improved on increasing the added amount of Fe3O4 particles and TA oligomers. Both Fe3O4 and TA can contribute to improved heating performance, but Fe3O4 possesses a greater contribution than TA does. Hence, the main source for increasing the composites’ temperature is Neel relaxation loss from Fe3O4 magnetic particles.


1990 ◽  
Vol 26 (3) ◽  
pp. 1149-1152 ◽  
Author(s):  
Shu-Guang Zhang ◽  
Zhen-Sheng Gao ◽  
Shou-Ting Jiang ◽  
Liang-Xue Wu

1990 ◽  
Vol 206 ◽  
Author(s):  
John K. Vassiliou ◽  
Vivek Mehrotra ◽  
Michael W. Russell ◽  
Emmanuel P. Giannelis

ABSTRACTNanometer-scale iron oxide magnetic particles have been formed in the porous network of a cross-linked polymer matrix by ion exchange and subsequent hydrolysis. The oxide particles are uniform, well-dispersed and spherical with a diameter ranging between 30 and 1200 Å depending on the synthesis conditions. The DC magnetic susceptibility, measured between 4 and 300 K, continuously increases with decreasing temperature and tends to saturate at low temperatures. Composites containing iron oxide particles with an average diameter of 80 Å exhibit superparamagnetism while those on the order of 1000 Å undergo an antiferromagnetic-type transition at 33 K. The magnetic susceptibility is critically dependent upon the particle size and the strength of the magnetic field.


2000 ◽  
Vol 15 (10) ◽  
pp. 2114-2120 ◽  
Author(s):  
Toshinobu Yogo ◽  
Tomoyuki Nakamura ◽  
Wataru Sakamoto ◽  
Shin-ichi Hirano

A transparent magnetic particle/organic film was synthesized from an iron–organic compound. Iron(III) 3-allylacetylacetonate (IAA) was polymerized followed by in situ hydrolysis yielding an iron oxide particle/oligomer hybrid. The sizes of magnetic particles were dependent upon the hydrolysis conditions of the IAA oligomers. A nanometer-sized ferrimagnetic iron oxide particle/oligomer hybrid showed a magnetization curve with no coercive force at 300 K and that with Hc of 200 Oe at 4.2 K, respectively. The magnetization versus H/T curves at 300 and 77 K were superimposed on each other and satisfied the Langevin equation. The transparent hybrid film showed a magnetization curve at room temperature. The absorption spectrum of the film was shifted to higher energy by 0.14 eV compared with that of bulk magnetite. The absorption edge of the film was blue-shifted.


Author(s):  
Georgios Banis ◽  
Maria Elisavet Kouli ◽  
Evangelos Hristoforou ◽  
Angelo Ferraro

Bio-separation of natural molecules as well as clinical compounds has been constantly developed in last decades. Several techniques are available but the majority of them presents drawbacks such us impossibility to be applied for industrial purposes. The main limitations for the scaling up are high costs and the fact that the devices work with microfluid dynamics. Nevertheless, magnetic bio-separation is considered the most prone to be used for large scale applications. Herein, we propose a simple magnetic separation method that is not based on microfluid dynamics, can work in a continuous- and high-flow rate and can be easily automated in order to be used for standard separation purposes. It is based on the use of an anisotropic flexible ferric magnetic strip, Teflon hoses and a pumping device. We show the modelling of the separation process along with an experimental test on iron oxide magnetic particles. The results showed that it is possible to remove, and separately collect, more than 92% of magnetic particles from a liquid solution of 100 ml in roughly 15 minutes.


2007 ◽  
Vol 6 (4) ◽  
pp. 7290.2007.00025 ◽  
Author(s):  
Rita E. Serda ◽  
Natalie L. Adolphi ◽  
Marco Bisoffi ◽  
Laurel O. Sillerud

Antibody-conjugated iron oxide nanoparticles offer a specific and sensitive tool to enhance magnetic resonance (MR) images of both local and metastatic cancer. Prostate-specific membrane antigen (PSMA) is predominantly expressed on the neovasculature of solid tumors and on the surface of prostate cells, with enhanced expression following androgen deprivation therapy. Biotinylated anti-PSMA antibody was conjugated to streptavidin-labeled iron oxide nanoparticles and used in MR imaging and confocal laser scanning microscopic imaging studies using LNCaP prostate cancer cells. Labeled iron oxide nanoparticles are internalized by receptor-mediated endocytosis, which involves the formation of clathrin-coated vesicles. Endocytosed particles are not targeted to the Golgi apparatus for recycling but instead accumulate within lysosomes. In T1-weighted MR images, the signal enhancement owing to the magnetic particles was greater for cells with magnetic particles bound to the cell surface than for cells that internalized the particles. However, the location of the particles (surface vs internal) did not significantly alter their effect on T2-weighted images. Our findings indicate that targeting prostate cancer cells using PSMA offers a specific and sensitive technique for enhancing MR images.


Author(s):  
Aygun Nasibova ◽  
Rovshan Khalilov ◽  
Huseyn Abiyev ◽  
Taras Kavetskyy ◽  
Boris Trubitsin ◽  
...  

Plant leaves (Eldar pine (Pinus eldarica M.), fig (Ficus carica L.), and olive (Olea europaea L.)), collected in territories with different ecological conditions, of the Absheron Peninsula (Azerbaijan Republic) were studied by electron paramagnetic resonance spectroscopy (EPR). The generation of nanophase iron oxide magnetic particles in biological systems under the influence of stress factors was revealed. It was found that the process of biomineralization plays a role in the formation of biogenic iron oxide magnetic nanoparticles in plants and the generation of magnetite crystals in biological tissues, and stress factors have a stimulating effect on this phenomenon.


Micromachines ◽  
2020 ◽  
Vol 11 (3) ◽  
pp. 302 ◽  
Author(s):  
Seong-Eun Kim ◽  
My Van Tieu ◽  
Sei Young Hwang ◽  
Min-Ho Lee

The growing interest in magnetic materials as a universal tool has been shown by an increasing number of scientific publications regarding magnetic materials and its various applications. Substantial progress has been recently made on the synthesis of magnetic iron oxide particles in terms of size, chemical composition, and surface chemistry. In addition, surface layers of polymers, silica, biomolecules, etc., on magnetic particles, can be modified to obtain affinity to target molecules. The developed magnetic iron oxide particles have been significantly utilized for diagnostic applications, such as sample preparations and biosensing platforms, leading to the selectivity and sensitivity against target molecules and the ease of use in the sensing systems. For the process of sample preparations, the magnetic particles do assist in target isolation from biological environments, having non-specific molecules and undesired molecules. Moreover, the magnetic particles can be easily applied for various methods of biosensing devices, such as optical, electrochemical, and magnetic phenomena-based methods, and also any methods combined with microfluidic systems. Here we review the utilization of magnetic materials in the isolation/preconcentration of various molecules and cells, and their use in various techniques for diagnostic biosensors that may greatly contribute to future innovation in point-of-care and high-throughput automation systems.


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