Artigos de revistas: "Iron oxide microparticles"

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Bica, Ioan, Eugen Mircea Anitas, Hyoung Jin Choi e Paula Sfirloaga. "Microwave-assisted synthesis and characterization of iron oxide microfibers". Journal of Materials Chemistry C 8, n.º 18 (2020): 6159–67. http://dx.doi.org/10.1039/c9tc05687d.

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Carrelo, Henrique, André R. Escoval, Tânia Vieira, Mercedes Jiménez-Rosado, Jorge Carvalho Silva, Alberto Romero, Paula Isabel P. Soares e João Paulo Borges. "Injectable Thermoresponsive Microparticle/Hydrogel System with Superparamagnetic Nanoparticles for Drug Release and Magnetic Hyperthermia Applications". Gels 9, n.º 12 (15 de dezembro de 2023): 982. http://dx.doi.org/10.3390/gels9120982.

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Cancer is a disease that continues to greatly impact our society. Developing new and more personalized treatment options is crucial to decreasing the cancer burden. In this study, we combined magnetic polysaccharide microparticles with a Pluronic thermoresponsive hydrogel to develop a multifunctional, injectable drug delivery system (DDS) for magnetic hyperthermia applications. Gellan gum and alginate microparticles were loaded with superparamagnetic iron oxide nanoparticles (SPIONs) with and without coating. The magnetic microparticles’ registered temperature increases up to 4 °C upon the application of an alternating magnetic field. These magnetic microparticles were mixed with drug-loaded microparticles, and, subsequently, this mixture was embedded within a Pluronic thermoresponsive hydrogel that is capable of being in the gel state at 37 °C. The proposed DDS was capable of slowly releasing methylene blue, used as a model drug, for up to 9 days. The developed hydrogel/microparticle system had a smaller rate of drug release compared with microparticles alone. This system proved to be a potential thermoresponsive DDS suitable for magnetic hyperthermia applications, thus enabling a synergistic treatment for cancer.

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Krajewski, M., K. Brzozka, W. S. Lin, H. M. Lin, M. Tokarczyk, J. Borysiuk, G. Kowalski e D. Wasik. "High temperature oxidation of iron–iron oxide core–shell nanowires composed of iron nanoparticles". Physical Chemistry Chemical Physics 18, n.º 5 (2016): 3900–3909. http://dx.doi.org/10.1039/c5cp07569f.

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Koudelkova, Zuzana, Zuzana Bytesnikova, Kledi Xhaxhiu, Monika Kremplova, David Hynek, Vojtech Adam e Lukas Richtera. "Electrochemical Evaluation of Selenium (IV) Removal from Its Aqueous Solutions by Unmodified and Modified Graphene Oxide". Molecules 24, n.º 6 (18 de março de 2019): 1063. http://dx.doi.org/10.3390/molecules24061063.

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The removal of selenium from superficial and waste water is a worldwide problem. The maximum limit according to the World Health Organization (WHO) for the selenium in the water is set at a concentration of 10 μg/L. Carbon based adsorbents have attracted much attention and recently demonstrated promising performance in removal of selenium. In this work, several materials (iron oxide based microparticles and graphene oxides materials) and their composites were prepared to remove Se(IV) from water. The graphene oxides were prepared according to the simplified Hummer’s method. In addition, the effect of pH, contact time and initial Se(IV) concentration was tested. An electrochemical method such as the differential pulse cathodic stripping voltammetry was used to determine the residual selenium concentration. From the experimental data, Langmuir adsorption model was used to calculate the maximum adsorption capacity. Graphene oxide particles modified by iron oxide based microparticles was the most promising material for the removal of Se(IV) from its aqueous solution at pH 2.0. Its adsorption efficiency reached more than 90% for a solution with given Se(IV) concentration, meanwhile its maximal recorded adsorption capacity was 18.69 mg/g.

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Žaimis, Uldis, Jūratė Jolanta Petronienė, Andrius Dzedzickis e Vytautas Bučinskas. "Stretch Sensor: Development of Biodegradable Film". Sensors 24, n.º 2 (21 de janeiro de 2024): 683. http://dx.doi.org/10.3390/s24020683.

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This article presents research on biodegradable stretch sensors produced using biological material. This sensor uses a piezoresistive effect to indicate stretch, which can be used for force measurement. In this work, an attempt was made to develop the composition of a sensitive material and to design a sensor. The biodegradable base was made from a κ-carrageenan compound mixed with Fe2O3 microparticles and glycerol. The influence of the weight fraction and iron oxide microparticles on the tensile strength and Young’s modulus was experimentally investigated. Tensile test specimens consisted of 10–25% iron oxide microparticles of various sizes. The results showed that increasing the mass fraction of the reinforcement improved the Young’s modulus compared to the pure sample and decreased the elongation percentage. The GF of the developed films varies from 0.67 to 10.47 depending on composition. In this paper, it was shown that the incorporation of appropriate amounts of Fe2O3 microparticles into κ-carrageenan can achieve dramatic improvements in mechanical properties, resulting in elongation of up to 10%. The developed sensors were experimentally tested, and their sensitivity, stability, and range were determined. Finally, conclusions were drawn on the results obtained.

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Kabiri, Shervin, Mahaveer D. Kurkuri, Tushar Kumeria e Dusan Losic. "Frit-free PDMS microfluidic device for chromatographic separation and on-chip detection". RSC Adv. 4, n.º 29 (2014): 15276–80. http://dx.doi.org/10.1039/c4ra01393j.

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A simple frit-free PDMS (polydimethylsiloxane) microfluidic chromatographic separation and detection device, packed with diatomaceous earth (DE) microparticles as a normal phase stationary material using iron oxide magnetic nanoparticles is described.

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Matsunaga, H., M. Kiguchi, B. Roth e P. D. Evans. "Visualisation of Metals in Pine Treated with Preservative Containing Copper and Iron Nanoparticles". IAWA Journal 29, n.º 4 (2008): 387–96. http://dx.doi.org/10.1163/22941932-90000193.

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In this study we compared the ability of conventional and field-emission scanning-electron-microscopy (FESEM) and energy-dispersive analysis of X-rays (EDX) to visualise and map inorganic nano and microparticles in Southern pine (Pinus sp.) treated with an aqueous dispersion of micronised copper-carbonate and iron oxide. Conventional SEM-EDX was able to detect areas of the wood microstructure that contained higher concentrations of copper and iron, but EDX maps were affected by drift and specimens suffered beam damage. The high brightness of the FESEM's electron beam at low accelerating voltages reduced beam damage and helped when mapping the distribution of copper and iron particles. The clarity of EDX maps was further improved by using drift-correction software and by mapping low energy X-rays. FESEM-EDX was able to resolve individual copper and iron microparticles. We conclude that FESEM-EDX shows promise as a means of resolving and mapping the distribution of inorganic metal particles in wood and that this may lead to greater use of the technology as interest in the treatment of wood with inorganic nano and microparticles grows.

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Tronc, E., e D. Bonnin. "Magnetic coupling among spinel iron oxide microparticles by Mössbauer spectroscopy". Journal de Physique Lettres 46, n.º 10 (1985): 437–43. http://dx.doi.org/10.1051/jphyslet:019850046010043700.

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Rodríguez, Cristian F., Paula Guzmán-Sastoque, Carolina Muñoz-Camargo, Luis H. Reyes, Johann F. Osma e Juan C. Cruz. "Enhancing Magnetic Micro- and Nanoparticle Separation with a Cost-Effective Microfluidic Device Fabricated by Laser Ablation of PMMA". Micromachines 15, n.º 8 (22 de agosto de 2024): 1057. http://dx.doi.org/10.3390/mi15081057.

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Superparamagnetic iron oxide micro- and nanoparticles have significant applications in biomedical and chemical engineering. This study presents the development and evaluation of a novel low-cost microfluidic device for the purification and hyperconcentration of these magnetic particles. The device, fabricated using laser ablation of polymethyl methacrylate (PMMA), leverages precise control over fluid dynamics to efficiently separate magnetic particles from non-magnetic ones. We assessed the device’s performance through Multiphysics simulations and empirical tests, focusing on the separation of magnetite nanoparticles from blue carbon dots and magnetite microparticles from polystyrene microparticles at various total flow rates (TFRs). For nanoparticle separation, the device achieved a recall of up to 93.3 ± 4% and a precision of 95.9 ± 1.2% at an optimal TFR of 2 mL/h, significantly outperforming previous models, which only achieved a 50% recall. Microparticle separation demonstrated an accuracy of 98.1 ± 1% at a TFR of 2 mL/h in both simulations and experimental conditions. The Lagrangian model effectively captured the dynamics of magnetite microparticle separation from polystyrene microparticles, with close agreement between simulated and experimental results. Our findings underscore the device’s robust capability in distinguishing between magnetic and non-magnetic particles at both micro- and nanoscales. This study highlights the potential of low-cost, non-cleanroom manufacturing techniques to produce high-performance microfluidic devices, thereby expanding their accessibility and applicability in various industrial and research settings. The integration of a continuous magnet, as opposed to segmented magnets in previous designs, was identified as a key factor in enhancing magnetic separation efficiency.

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Havelka, Ondřej, Martin Cvek, Michal Urbánek, Dariusz Łukowiec, Darina Jašíková, Michal Kotek, Miroslav Černík, Vincenzo Amendola e Rafael Torres-Mendieta. "On the Use of Laser Fragmentation for the Synthesis of Ligand-Free Ultra-Small Iron Nanoparticles in Various Liquid Environments". Nanomaterials 11, n.º 6 (10 de junho de 2021): 1538. http://dx.doi.org/10.3390/nano11061538.

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Traditionally, the synthesis of nanomaterials in the ultra-small size regime (1–3 nm diameter) has been linked with the employment of excessive amounts of hazardous chemicals, inevitably leading to significant environmentally detrimental effects. In the current work, we demonstrate the potential of laser fragmentation in liquids (LFL) to produce highly pure and stable iron ultra-small nanoparticles. This is carried out by reducing the size of carbonyl iron microparticles dispersed in various polar solvents (water, ethanol, ethylene glycol, polyethylene glycol 400) and liquid nitrogen. The explored method enables the fabrication of ligand-free iron oxide ultra-small nanoparticles with diameter in the 1–3 nm range, a tight size distribution, and excellent hydrodynamic stability (zeta potential > 50 mV). The generated particles can be found in different forms, including separated ultra-small NPs, ultra-small NPs forming agglomerates, and ultra-small NPs together with zero-valent iron, iron carbide, or iron oxide NPs embedded in matrices, depending on the employed solvent and their dipolar moment. The LFL technique, aside from avoiding chemical waste generation, does not require any additional chemical agent, other than the precursor microparticles immersed in the corresponding solvent. In contrast to their widely exploited chemically synthesized counterparts, the lack of additives and chemical residuals may be of fundamental interest in sectors requiring colloidal stability and the largest possible number of chemically active sites, making the presented pathway a promising alternative for the clean design of new-generation nanomaterials.

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Knoche Gupta, Krysti, Heung Chan Lee, Joshua Richard Coduto e Johna Leddy. "(Invited) Glassy Carbon Electrodes Modified with Micromagnets: Magnetoelectrocatalysis of HER". ECS Meeting Abstracts MA2022-02, n.º 30 (9 de outubro de 2022): 1112. http://dx.doi.org/10.1149/ma2022-02301112mtgabs.

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Electrode kinetics for the hydrogen evolution reaction (HER) on glassy carbon electrodes are inherently slow. Voltammetric responses are marked by large overpotentials η and small exchange current densities j0. HER rates are markedly increased on glassy carbon electrodes modified with composites of Nafion® and siloxane coated micromagnets. Comparison of linear sweep voltammograms of glassy carbon electrodes modified with either Nafion films or composites of magnetized iron oxide microparticles identifies enhanced HER rates where magnetic gradients are established. For magnetized 1 𝜇m γ-Fe2O3 microparticles in Nafion, η is decreased by 0.191 ± 0.019 V at 0.4 mA cm-2 compared to Nafion films. This corresponds to an energetic advantage of -18.4 kJ/mol and a 40-fold increase in j0. For magnetized 5 𝜇m Fe3O4 microparticles in Nafion, η is decreased by 0.28 V at 0.4 mA cm-2, which corresponds to an energetic advantage of -27 kJ/mol and 230-fold increase in exchange current. HER rate on platinum electrodes is unchanged for Pt electrodes modified with Nafion films and with composites of magnetized micromagnets in Nafion. Enhancements are not due to either magnetohydrodynamics or mediation as there is no bulk solvent volume in Nafion to convect and siloxane coating renders the iron oxide microparticles chemically and electrochemically inert. Voltammetry for glassy carbon electrodes modified with Nafion films and with composites of Nafion and demagnetized microparticles are comparable. The chemistry of magnetized and demagnetized composites are the same; the rate enhancements arises from the physical impact of the magnetic gradients in the magnetized composites. The enhanced rate for HER on glassy carbon arises through magnetoelectrocatalysis. Work is undertaken at the University of Iowa. The National Science Foundation (NSF CHE-1309366 and NSF CHE-0809745) and the Army Research Office (W911NF-19-1-0208 (74912-CH-II)) supported these projects.

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Amara, Daniel, e Shlomo Margel. "Synthesis and characterization of elemental iron and iron oxide nano/microcomposite particles by thermal decomposition of ferrocene". Nanotechnology Reviews 2, n.º 3 (1 de junho de 2013): 333–57. http://dx.doi.org/10.1515/ntrev-2012-0061.

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AbstractThe unique chemical and physical properties of the nano and microscale materials have led to important roles in the several scientific and technological fields. The magnetic nano/microparticles are of great interest because of its potential applications in, e.g., hyperthermia, magnetic resonance imaging (MRI), catalytic applications, etc. The decomposition of iron pentacarbonyl is one of the most common methods for the preparation of magnetic iron oxide and iron nanoparticles. However, Fe(CO)5 is severely toxic and alternative precursors should be used. Here, we describe the recent advances in the synthesis and characterization of the elemental iron and iron oxide nano/microcomposite particles by the thermal decomposition of ferrocene. The described synthesis process is based on simple nontoxic approaches including, for example, a solventless process. The particle size and size distribution as well as their composition, crystallinity, shape, and magnetic properties can be controlled via the synthesis conditions.

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Rafieepour, Athena, Mansour R. Azari, Habibollah Peirovi, Fariba Khodagholi, Jalal Pourahmad Jaktaji, Yadollah Mehrabi, Parvaneh Naserzadeh e Yousef Mohammadian. "Investigation of the effect of magnetite iron oxide particles size on cytotoxicity in A549 cell line". Toxicology and Industrial Health 35, n.º 11-12 (novembro de 2019): 703–13. http://dx.doi.org/10.1177/0748233719888077.

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Introduction: Magnetite as iron oxide is widely used in various industries, in the pharmaceutical industry in particular where it is used for its magnetic properties. The environmental and occupational exposure to airborne nanoparticles and microparticles of iron oxide compounds have been reported. Since authors have reported contradictory results, the objective of this study was to investigate the effect of particles’ size in their toxicities. Methods: The human cell line A549 was exposed with magnetite iron oxide in two size categories of micro (≥5 µm) and nano (<100 nm), with four concentrations of 10, 50, 100, and 250 µg/ml at two time periods of 24 and 72 h. The cell viability, reactive oxygen species (ROS), changes in mitochondrial membrane potential, and incidence of apoptosis were studied. Results: Nano and micro magnetite particles demonstrated diverse toxicity effects on the A549 cell line at the 24- and 72-h exposure periods; however, the effects produced were time- and concentration-dependent. Nano magnetite particles produced greater cellular toxicities in forms of decreased viabilities at concentration exposures greater than 50 µg/ml ( p < 0.05), along with increased ROS ( p < 0.05), decreased cellular membrane potential ( p < 0.05), and reduced rate of apoptosis ( p < 0.05). Discussion: The results of this study demonstrated that magnetite iron in nano-range sizes had a greater absorbability for the A549 cell line compared to micro sizes, and at the same time, nanoparticles were more toxic than microparticles, demonstrating higher production of ROS and decreased viabilities. Considering the greater toxicity of nanoparticles of magnetite iron in this study, thorough precautionary control measures must be taken before they can be used in various industries.

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Mel’nikov, G. Yu, L. M. Ranero, A. P. Safronov, A. Larrañaga, A. V. Svalov e G. V. Kurlyandskaya. "Epoxy Composites with Iron Oxide Microparticles: Model Materials for Magnetic Detection". Physics of Metals and Metallography 123, n.º 11 (novembro de 2022): 1075–83. http://dx.doi.org/10.1134/s0031918x22601330.

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Dalzon, Torres, Reymond, Gallet, Saint-Antonin, Collin-Faure, Moriscot et al. "Influences of Nanoparticles Characteristics on the Cellular Responses: The Example of Iron Oxide and Macrophages". Nanomaterials 10, n.º 2 (5 de fevereiro de 2020): 266. http://dx.doi.org/10.3390/nano10020266.

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Iron oxide nanoparticles/microparticles are widely present in a variety of environments, e.g., as a byproduct of steel and iron degradation, as, for example, in railway brakes (e.g., metro station) or in welding fumes. As all particulate material, these metallic nanoparticles are taken up by macrophages, a cell type playing a key role in the innate immune response, including pathogen removal phagocytosis, secretion of free radical species such as nitric oxide or by controlling inflammation via cytokine release. In this paper, we evaluated how macrophages functions were altered by two iron based particles of different size (100 nm and 20 nm). We showed that at high, but subtoxic concentrations (1 mg/mL, large nanoparticles induced stronger perturbations in macrophages functions such as phagocytic capacity (tested with fluorescent latex microspheres) and the ability to respond to bacterial endotoxin lipopolysaccharide stimulus (LPS) in secreting nitric oxide and pro-cytokines (e.g., Interleukin-6 (IL-6) and Tumor Necrosis Factor (TNF)). These stronger effects may correlate with an observed stronger uptake of iron for the larger nanoparticles.

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Thébault, C., M. Marmiesse, C. Naud, K. Pernet-Gallay, E. Billiet, H. Joisten, B. Dieny, M. Carrière, Y. Hou e R. Morel. "Magneto-mechanical treatment of human glioblastoma cells with engineered iron oxide powder microparticles for triggering apoptosis". Nanoscale Advances 3, n.º 21 (2021): 6213–22. http://dx.doi.org/10.1039/d1na00461a.

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In this work we present a new type of magnetite microparticles made by ball milling and study the influence of PEG surface functionalization on their ability to induce cell death when subjected to a low frequency magnetic field.

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Dresvyannikov, A. F., L. E. Kalugin, M. M. Mironov e M. F. Shaekhov. "Influence of plasma high-frequency induction discharge on the physical and chemical properties of the Ti – Fe – Ni dispersed system obtained by the electrochemical method". Physics and Chemistry of Materials Treatment 4 (2022): 15–22. http://dx.doi.org/10.30791/0015-3214-2022-4-15-22.

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The Ti – Fe – Ni dispersed system was synthesized by the method of contact exchange on the surface of dispersed titanium in an aqueous chloride-containing solution of iron and nickel. The morphology and composition of the surface, as well as the actual phase composition of the Ti – Fe – Ni dispersed system before and after plasma treatment, have been studied by X-ray phase analysis, scanning electron microscopy and Auger spectroscopy. It is shown that on the surface of titanium microparticles, separate spherical subindividuals and their agglomerates are formed, characterized by nanosizes (100 – 200 nm). It was also found that the Ti – Fe – Ni system contains highly distorted metallic phases of iron and nickel, as well as a hydride phase of TiH2, which practically do not undergo phase transformations as a result of the passage of low-pressure argon through an inductively coupled plasma discharge. It is shown that the metallic phases of titanium, iron, and nickel are characterized by the presence of a thin oxide film on the particle surface, and the total content of the oxide phase in the samples does not exceed 1.5 wt. %. The treatment of the Ti – Fe – Ni system microparticles by high frequency induction discharge in low-pressureargon leads to small changes in the content of phases, the lattice constant and the microstructure of the system under study.It indicates a certain solubility of elements in each other and a greater crystallinity of the phases relative to those in particles untreated by plasma.

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Pipíška, Martin, Simona Zarodňanská, Miroslav Horník, Libor Ďuriška, Marián Holub e Ivo Šafařík. "Magnetically Functionalized Moss Biomass as Biosorbent for Efficient Co2+ Ions and Thioflavin T Removal". Materials 13, n.º 16 (16 de agosto de 2020): 3619. http://dx.doi.org/10.3390/ma13163619.

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Microwave synthesized iron oxide nanoparticles and microparticles were used to prepare a magnetically responsive biosorbent from Rhytidiadelphus squarrosus moss for the rapid and efficient removal of Co2+ ions and thioflavin T (TT). The biocomposite was extensively characterized using Fourier transformed infrared (FTIR), XRD, SEM, and EDX techniques. The magnetic biocomposite showed very good adsorption properties toward Co2+ ions and TT e.g., rapid kinetics, high adsorption capacity (218 μmol g−1 for Co and 483 μmol g−1 for TT), fast magnetic separation, and good reusability in four successive adsorption–desorption cycles. Besides the electrostatic attraction between the oxygen functional moieties of the biomass surface and both Co2+ and TT ions, synergistic interaction with the –FeOH groups of iron oxides also participates in adsorption. The obtained results indicate that the magnetically responsive biocomposite can be a suitable, easily separable, and recyclable biosorbent for water purification.

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Chistè, Elena, Gloria Ischia, Marco Gerosa, Pasquina Marzola, Marina Scarpa e Nicola Daldosso. "Porous Si Microparticles Infiltrated with Magnetic Nanospheres". Nanomaterials 10, n.º 3 (4 de março de 2020): 463. http://dx.doi.org/10.3390/nano10030463.

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Porous silicon (pSi) microparticles obtained by porosification of crystalline silicon wafers have unique optical properties that, together with biodegradability, biocompatibility and absence of immunogenicity, are fundamental characteristics to candidate them as tracers in optical imaging techniques and as drug carriers. In this work, we focus on the possibility to track down the pSi microparticles also by MRI (magnetic resonance imaging), thus realizing a comprehensive tool for theranostic applications, i.e., the combination of therapy and diagnostics. We have developed and tested an easy, quick and low-cost protocol to infiltrate the COOH-functionalized pSi microparticles pores (tens of nanometers about) with magnetic nanospheres (SPIONs—Super Paramagnetic Iron Oxide Nanoparticles, about 5–7 nm) and allow an electrostatic interaction. The structural properties and the elemental composition were investigated by electron microscopy techniques coupled to elemental analysis to demonstrate the effective attachment of the SPIONs along the pores’ surface of the pSi microparticles. The magnetic properties were investigated under an external magnetic field to determine the relaxivity properties of the material and resulting in an alteration of the relaxivity of water due to the SPIONs presence, clearly demonstrating the effectiveness of the easy functionalization protocol proposed.

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SMIRNOV, V. M., G. P. VORONKOV, V. G. SEMENOV, V. G. POVAROV e I. V. MURIN. "MÖSSBAUER STUDY OF STRUCTURAL–CHEMICAL TRANSFORMATION IN TWO-DIMENSIONAL IRON–OXYGEN NANOSTRUCTURES IN THE COURSE OF TRANSPORT REDUCTION". Surface Review and Letters 07, n.º 01n02 (fevereiro de 2000): 1–6. http://dx.doi.org/10.1142/s0218625x00000026.

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Structural–chemical transformations of quasi-two-dimensional iron–oxygen nanostructures occurring at transport reduction were studied using NGR spectroscopy. It has been found that isolated iron–oxygen groups [i.e. groups containing iron and oxygen atoms: ≡Si–O–Fe(OH)2 and (≡Si–O–)2–FeOH] forming surface monolayers were not reduced at T = 400–600° C because of their covalent bonding with the silica surface. Reduction of iron oxide microparticles (microstructures) at T ≥ 600°C C resulted in the formation of metal iron in the form of α-Fe. It has been revealed that in the course of transport reduction (TR) of the samples with deposited monolayers (one or four monolayers) at T ≥ 600° C bulk phases of iron silicate and metal iron were formed. It has also been shown that the features of structural–chemical transformations of supported iron–oxygen nanolayers were in relation with the specific character of phase formation within nanoscale structures.

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Pospiskova, K., G. Prochazkova e I. Safarik. "One-step magnetic modification of yeast cells by microwave-synthesized iron oxide microparticles". Letters in Applied Microbiology 56, n.º 6 (4 de abril de 2013): 456–61. http://dx.doi.org/10.1111/lam.12069.

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Möller, Winfried, Gerhard Scheuch, Knut Sommerer e Joachim Heyder. "Preparation of spherical monodisperse ferrimagnetic iron-oxide microparticles between 1 and 5μm diameter". Journal of Magnetism and Magnetic Materials 225, n.º 1-2 (janeiro de 2001): 8–16. http://dx.doi.org/10.1016/s0304-8853(00)01221-x.

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Oliveira, João Pedro Jenson de, Acelino Cardoso de Sá e Leonardo Lataro Paim. "Electrocatalysis of Ethanol and Methanol Electrooxidation by Composite Electrodes with NiOOH/FeOOH Supported on Reduced Graphene Oxide onto Composite Electrodes". Chemistry Proceedings 2, n.º 1 (9 de novembro de 2020): 2. http://dx.doi.org/10.3390/eccs2020-07523.

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This paper presents graphite/paraffin composite electrodes modified with microparticles of nickel (Ni) and Ni-Fe alloy anchored in reduced graphene oxide (rGO); these electrodes were made by electrosynthesis. Firstly, the electrodeposition of reduced graphene oxide was made by cyclic voltammetry (CV) onto the graphite/paraffin electrodes’ surface. After electrodeposition of the rGO, iron and nickel were electrodeposited by CV with successive scans. Finally, the formation of iron-nickel oxyhydroxide on the electrode surface was performed by cyclic voltammetry in alkaline medium. The composites were investigated by field emission gun scanning electron microscopy (FEG-SEM); it was observed that the Ni microparticles had spherical shapes, while the Ni-Fe alloy did not present a defined shape. The composite electrodes were used to analysis ethanol and methanol electrooxidation in an alkaline medium of 0.10 mol L−1 of NaOH in a potential range of from −0.20 to 1.0 V (vs. Ag/AgCl) at 50 mV s−1 by CV. The electrodes were able to make the electrooxidation of ethanol at a potential of around 0.57 V for the electrode constituted by the Ni-Fe alloy and around 0.61 V for the electrode modified with Ni, and for methanol in a potential around 0.57 V for the Ni-Fe alloy and around 0.66 V for the Ni electrode. The Ni-Fe alloy electrodes showed the electrocatalysis of the alcohols in relation to Ni electrodes.

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Katsnelson, Boris A., Larisa I. Privalova, Sergey V. Kuzmin, Vladimir B. Gurvich, Marina P. Sutunkova, Ekaterina P. Kireyeva e Ilzira A. Minigalieva. "An Approach to Tentative Reference Levels Setting for Nanoparticles in the Workroom Air Based on Comparing Their Toxicity with That of Their Micrometric Counterparts: A Case Study of Iron Oxide Fe3O4". ISRN Nanotechnology 2012 (7 de agosto de 2012): 1–12. http://dx.doi.org/10.5402/2012/143613.

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We overview the state of the art in the field of safe exposure levels setting for nanomaterials together with the previously published results of our experimental investigations characterizing comparative toxicity of the iron oxide (magnetite) in the form of microparticles and nanoparticles of different size and comparative activity of the defensive alveolar phagocytosis response to their pulmonary deposition. An approach to the substantiation of acceptable workplace exposure limits of metallic nanoparticles is discussed and, specifically, the tentative reference level for magnetite nanoparticles is recommended.

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Dolmatov, Arthur V., Sergey S. Maklakov, Anastasia V. Artemova, Dmitry A. Petrov, Artem O. Shiryaev e Andrey N. Lagarkov. "Deposition of Thick SiO2 Coatings to Carbonyl Iron Microparticles for Thermal Stability and Microwave Performance". Sensors 23, n.º 3 (3 de fevereiro de 2023): 1727. http://dx.doi.org/10.3390/s23031727.

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Thick dielectric SiO2 shells on the surface of iron particles enhance the thermal and electrodynamic parameters of the iron. A technique to deposit thick, 500-nm, SiO2 shell to the surface of carbonyl iron (CI) particles was developed. The method consists of repeated deposition of SiO2 particles with air drying between iterations. This method allows to obtain thick dielectric shells up to 475 nm on individual CI particles. The paper shows that a thick SiO2 protective layer reduces the permittivity of the ‘Fe-SiO2—paraffin’ composite in accordance with the Maxwell Garnett medium theory. The protective shell increases the thermal stability of iron, when heated in air, by shifting the transition temperature to the higher oxide. The particle size, the thickness of the SiO2 shells, and the elemental analysis of the samples were studied using a scanning electron microscope. A coaxial waveguide and the Nicholson–Ross technique were used to measure microwave permeability and permittivity of the samples. A vibrating-sample magnetometer (VSM) was used to measure the magnetostatic data. A synchronous thermal analysis was applied to measure the thermal stability of the coated iron particles. The developed samples can be applied for electromagnetic compatibility problems, as well as the active material for various types of sensors.

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Murashova, Nataliya M., Ayuna A. Dambieva e Evgeniy V. Yurtov. "EFFECT OF NANO- AND MICROPARTICLES OF IRON (III) OXIDE ON VISCOSITY OF LAMELLAR LIQUID CRYSTALS OF LECITHIN". IZVESTIYA VYSSHIKH UCHEBNYKH ZAVEDENIY KHIMIYA KHIMICHESKAYA TEKHNOLOGIYA 59, n.º 5 (12 de julho de 2018): 41. http://dx.doi.org/10.6060/tcct.20165905.5330.

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The addition of low concentrations (0.001 – 0.1 wt. %) of iron (III) oxide nanoparticles with diameter of 10-20 nm was shown to result in the increase in a viscosity of lamellar liquid crystals in the systems of lecithin – water and lecithin – dodecane – water by 35-60% and 15-20%, respectively, whereas the addition of 1-5 µm microparticles does not affect the viscosity. An increase in a viscosity of the liquid crystals with the growth of the nanoparticles concentration from 0.001 to 0.1 wt. % is observed. It is assumed that the nanoparticles act as "bridges" between the bilayers of the lamellar liquid crystal.

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McAteer, Martina A., Nicola R. Sibson, Constantin von zur Muhlen, Jurgen E. Schneider, Andrew S. Lowe, Nicholas Warrick, Keith M. Channon, Daniel C. Anthony e Robin P. Choudhury. "In vivo magnetic resonance imaging of acute brain inflammation using microparticles of iron oxide". Nature Medicine 13, n.º 10 (23 de setembro de 2007): 1253–58. http://dx.doi.org/10.1038/nm1631.

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Zhu, Yeqing, You Ling, Jinglian Zhong, Xueguo Liu, Kun Wei e Suiqiao Huang. "Magnetic resonance imaging of radiation-induced brain injury using targeted microparticles of iron oxide". Acta Radiologica 53, n.º 7 (setembro de 2012): 812–19. http://dx.doi.org/10.1258/ar.2012.120040.

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Xu, Chenjie, David Miranda-Nieves, James A. Ankrum, Mads Emil Matthiesen, Joseph A. Phillips, Isaac Roes, Gregory R. Wojtkiewicz et al. "Tracking Mesenchymal Stem Cells with Iron Oxide Nanoparticle Loaded Poly(lactide-co-glycolide) Microparticles". Nano Letters 12, n.º 8 (12 de julho de 2012): 4131–39. http://dx.doi.org/10.1021/nl301658q.

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Yan, Fei, Wei Yang, Xiang Li, Hongmei Liu, Xiang Nan, Lisi Xie, Dongliang Zhou et al. "Magnetic Resonance Imaging of Atherosclerosis Using CD81-Targeted Microparticles of Iron Oxide in Mice". BioMed Research International 2015 (21 de julho de 2015): 1–10. http://dx.doi.org/10.1155/2015/758616.

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The goal of this study is to investigate the feasibility of using CD81- (Cluster of Differentiation 81 protein-) targeted microparticles of iron oxide (CD81-MPIO) for magnetic resonance imaging (MRI) of the murine atherosclerosis. CD81-MPIO and IgG- (Immunoglobulin G-) MPIO were prepared by covalently conjugating, respectively, with anti-CD81 monoclonal and IgG antibodies to the surface of the tosyl activated MPIO. The relevant binding capability of the MPIO was examined by incubating them with murine bEnd.3 cells stimulated with phenazine methosulfate (PMS) and its effect in shortening T2 relaxation time was also examined. MRI in apolipoprotein E-deficient mice was studied in vivo. Our results show that CD81-MPIO, but not IgG-MPIO, can bind to the PMS-stimulated bEnd.3 cells. The T2 relaxation time was significantly shortened for stimulated bEnd.3 cells when compared with IgG-MPIO. In vivo MRI in apolipoprotein E-deficient mice showed highly conspicuous areas of low signal after CD81-MPIO injection. Quantitative analysis of the area of CD81-MPIO contrast effects showed 8.96- and 6.98-fold increase in comparison with IgG-MPIO or plain MPIO, respectively (P<0.01). Histological assay confirmed the expression of CD81 and CD81-MPIO binding onto atherosclerotic lesions. In conclusion, CD81-MPIO allows molecular assessment of murine atherosclerotic lesions by magnetic resonance imaging.

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Kothari, Manisha S., Ashraf Aly Hassan e Kosha A. Shah. "Three-Dimensional Electrochemical Oxidation of Recalcitrant Dye Using Green Iron Microparticles". Water 13, n.º 14 (12 de julho de 2021): 1925. http://dx.doi.org/10.3390/w13141925.

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This study evaluated the effect of the addition of green iron microparticles (Fe-MPs) as a three-dimensional electrode on efficiency of the electrochemical oxidation process. Polyphenols present in green tea extract act as a reducing and capping agent during green synthesis of the Fe-MPs. Scanning electron microscopy and energy-dispersive X-ray spectroscopy analysis indicates that the average size of particles is 100 µm, with about ~47 wt % of Fe in oxide form. The addition of Fe-MPs as a third electrode in the conventional electro-oxidation (EO) process converts it into a three-dimensional (3D) catalytic EO process to enhance the decolorization efficiency. Green synthesized Fe-MPs function as several microelectrodes in the process. Adsorption study indicated that only 12% of decolorization is due to adsorption on the Fe-MPs surface. Moreover, improvement in generation of hydroxyl radicals was validated by applying dimethyl sulfoxide as scavenger, and it was observed that generation of hydroxyl radicals decreased with the addition of DMSO. Results showed that decolorization efficiency increased in the 3D EO process with Fe-MPs by about 24% compared to the conventional 2D process without the Fe-MPs dosing, and initial pH as well as the Fe-MPs dose has a significant effect on decolorization efficiency during the 3D process. It is observed that reaction works better at highly acidic pH (2-4), and decolorization efficiency improved with higher doses of Fe-MPs.

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Reibenspies, Joseph H., e Nattamai Bhuvanesh. "X-ray powder diffraction characterization of iron microparticles on a Bruker SMART1000 single-crystal X-ray diffractometer". Powder Diffraction 24, n.º 4 (dezembro de 2009): 347–50. http://dx.doi.org/10.1154/1.3257614.

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A method to characterize iron oxide microparticles by microquantity X-ray powder diffraction is presented. The method employs small sections of acrylic tubing and double sided Mylar® tape that fits over a standard 170 mm collimator for a Bruker-AXS SMART 1000 or APEXII three-circle single-crystal diffractometer (Mo X-ray tube). The tubing will hold and position a sample that is placed on the double-sided Mylar® tape and allow for rapid specimen mounting/dismounting and data collection. The method is simple, portable, and readily adapted to a variety of single-crystal X-ray diffractometers.

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Thayse, Kathleen, Nadège Kindt, Sophie Laurent e Stéphane Carlier. "VCAM-1 Target in Non-Invasive Imaging for the Detection of Atherosclerotic Plaques". Biology 9, n.º 11 (29 de outubro de 2020): 368. http://dx.doi.org/10.3390/biology9110368.

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Atherosclerosis is a progressive chronic arterial disease characterised by atheromatous plaque formation in the intima of the arterial wall. Several invasive and non-invasive imaging techniques have been developed to detect and characterise atherosclerosis in the vessel wall: anatomic/structural imaging, functional imaging and molecular imaging. In molecular imaging, vascular cell adhesion molecule-1 (VCAM-1) is a promising target for the non-invasive detection of atherosclerosis and for the assessment of novel antiatherogenic treatments. VCAM-1 is an adhesion molecule expressed on the activated endothelial surface that binds leucocyte ligands and therefore promotes leucocyte adhesion and transendothelial migration. Hence, for several years, there has been an increase in molecular imaging methods for detecting VCAM-1 in MRI, PET, SPECT, optical imaging and ultrasound. The use of microparticles of iron oxide (MPIO), ultrasmall superparamagnetic iron oxide (USPIO), microbubbles, echogenic immunoliposomes, peptides, nanobodies and other nanoparticles has been described. However, these approaches have been tested in animal models, and the remaining challenge is bench-to-bedside development and clinical applicability.

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Bai, Meng-Yi, Mu-Hsien Yu, Ting-Teng Wang, Shiu-Hsin Chen e Yu-Chi Wang. "Plate-like Alginate Microparticles with Disulfiram–SPIO–Coencapsulation: An In Vivo Study for Combined Therapy on Ovarian Cancer". Pharmaceutics 13, n.º 9 (27 de agosto de 2021): 1348. http://dx.doi.org/10.3390/pharmaceutics13091348.

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Disulfiram is a drug used to support the treatment of chronic alcoholism. Recently, it has been found to have an off-label ability to inhibit the growth of ovarian cancer cells. However, the original formulation was designed for use via oral administration, which is not suitable to be given by a direct spray on the affected area. Therefore, in this study, we designed and prepared alginate (ALG) microparticles loaded with disulfiram and superparamagnetic iron oxide (cross-linking disulfiram/SPIO/ALG MPs), which have great potential application for inhibiting the growth of ovarian cancer simultaneously via two treatments, i.e., chemotherapy and hyperthermia. The drug-encapsulating alginate microparticles were prepared using an electrospray system and then cross-linked with calcium chloride ions. The particles were observed by optical microscopy and scanning electron microscopy, and found to be approximately 200 μm in diameter. The disc-shape morphology of the microparticles could be controlled by up to 95%. The drug-encapsulation efficiency of the microparticles reached 98%, and the suppression of tumor growth for the free-form disulfiram-treated group and disulfiram/SPIO/ALG MPs-treated group were 48.2% and 55.9% of tumor volume reduction, respectively, compared with a cisplatin-treated group. A hyperthermic effect can be achieved by applying a magnetic field to oscillate SPIO. The results of this study showed that these cross-linking disulfiram/SPIO/ALG MPs are potential drug carriers for the treatment of ovarian cancer.

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Araújo, Jefferson F. D. F., João M. B. Pereira e Antônio C. Bruno. "Assembling a magnetometer for measuring the magnetic propertiesof iron oxide microparticles in the classroom laboratory". American Journal of Physics 87, n.º 6 (junho de 2019): 471–75. http://dx.doi.org/10.1119/1.5100944.

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Wassel, Ronald A., Brian Grady, Richard D. Kopke e Kenneth J. Dormer. "Dispersion of super paramagnetic iron oxide nanoparticles in poly(d,l-lactide-co-glycolide) microparticles". Colloids and Surfaces A: Physicochemical and Engineering Aspects 292, n.º 2-3 (janeiro de 2007): 125–30. http://dx.doi.org/10.1016/j.colsurfa.2006.06.012.

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Möller, Winfried Barth, Martin Kohl, Winfried. "HUMAN ALVEOLAR LONG-TERM CLEARANCE OF FERROMAGNETIC IRON OXIDE MICROPARTICLES IN HEALTHY AND DISEASED SUBJECTS". Experimental Lung Research 27, n.º 7 (janeiro de 2001): 547–68. http://dx.doi.org/10.1080/019021401753181827.

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Tewes, Frederic, Carsten Ehrhardt e Anne Marie Healy. "Superparamagnetic iron oxide nanoparticles (SPIONs)-loaded Trojan microparticles for targeted aerosol delivery to the lung". European Journal of Pharmaceutics and Biopharmaceutics 86, n.º 1 (janeiro de 2014): 98–104. http://dx.doi.org/10.1016/j.ejpb.2013.09.004.

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Yassine, O., E. Q. Li, A. Alfadhel, A. Zaher, M. Kavaldzhiev, S. T. Thoroddsen e J. Kosel. "Magnetically Triggered Monodispersed Nanocomposite Fabricated by Microfluidic Approach for Drug Delivery". International Journal of Polymer Science 2016 (2016): 1–8. http://dx.doi.org/10.1155/2016/1219469.

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Responsive microgel poly(N-isopropylacrylamide) or PNIPAM is a gel that can swell or shrink in response to external stimuli (temperature, pH, etc.). In this work, a nanocomposite gel is developed consisting of PNIPAM and magnetic iron oxide nanobeads for controlled release of liquids (like drugs) upon exposure to an alternating magnetic field. Microparticles of the nanocomposite are fabricated efficiently with a monodisperse size distribution and a diameter ranging from 20 to 500 µm at a rate of up to 1 kHz using a simple and inexpensive microfluidic system. The nanocomposite is heated through magnetic losses, which is exploited for a remotely stimulated liquid release. The efficiency of the microparticles for controlled drug release applications is tested with a solution of Rhodamine B as a liquid drug model. In continuous and pulsatile mode, a release of 7% and 80% was achieved, respectively. Compared to external thermal actuation that heats the entire surrounding or embedded heaters that need complex fabrication steps, the magnetic actuation provides localized heating and is easy to implement with our microfluidic fabrication method.

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Król, Jarosƚaw E., e Garth D. Ehrlich. "Using SMART Magnetic Fluids and Gels for Prevention and Destruction of Bacterial Biofilms". Microorganisms 11, n.º 6 (7 de junho de 2023): 1515. http://dx.doi.org/10.3390/microorganisms11061515.

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Biofouling is a major problem in all natural and artificial settings where solid surfaces meet liquids in the presence of living microorganisms. Microbes attach to the surface and form a multidimensional slime that protects them from unfavorable environments. These structures, known as biofilms, are detrimental and very hard to remove. Here, we used SMART magnetic fluids [ferrofluids (FFs), magnetorheological fluids (MRFs), and ferrogels (FGs) containing iron oxide nano/microparticles] and magnetic fields to remove bacterial biofilms from culture tubes, glass slides, multiwell plates, flow cells, and catheters. We compared the ability of different SMART fluids to remove biofilms and found that commercially available, as well as homemade, FFs, MRFs, and FGs can successfully remove biofilm more efficiently than traditional mechanical methods, especially from textured surfaces. In tested conditions, SMARTFs reduced bacterial biofilms by five orders of magnitude. The ability to remove biofilm increased with the amount of magnetic particles; therefore, MRFs, FG, and homemade FFs with high amounts of iron oxide were the most efficient. We showed also that SMART fluid deposition can protect a surface from bacterial attachment and biofilm formation. Possible applications of these technologies are discussed.

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Мельников, Г. Ю., В. Н. Лепаловский e Г. В. Курляндская. "Магнитный импеданс пленочных наноструктур для оценки полей рассеяния микрочастиц магнитных композитов". Журнал технической физики 92, n.º 2 (2022): 321. http://dx.doi.org/10.21883/jtf.2022.02.52024.259-21.

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Longitudinal giant magnetoimpedance effect of [Fe21Ni79/Cu]5/Cu/[Fe21Ni79/Cu]5 film element was investigated depends on stray magnetic field of epoxy magnetic composite with 30 % weight concentration of iron oxide magnetic microparticles. Configuration of an experiment was a model of thrombus detection in a blood vessel. Stray magnetic field was varied by movement of a magnetic composite above the element perpendicular to the long side. Composite was either magnetized or not to the state of remanence. As the magnetic composite approaches the GMI element, MI ratio curves are smoothed and shifted along the field axis and maximum value of the MI ratio decreases. Magnetic properties of magnetic composite and film element were investigated as well.

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Мельников, Г. Ю., В. Н. Лепаловский, А. П. Сафронов, И. В. Бекетов, А. В. Багазеев, Д. С. Незнахин e Г. В. Курляндская. "Магнитные композиты на основе эпоксидной смолы с магнитными микро- и наночастицами оксида железа: фокус на магнитное детектирование". Физика твердого тела 65, n.º 7 (2023): 1100. http://dx.doi.org/10.21883/ftt.2023.07.55829.22h.

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Magnetic and structural properties iron oxide micro- and nanoparticles and composites based on epoxy resin at different mass concentrations of particles are investigated (0, 5, 10, 30%). Commercial Alfa Aesar microparticles and nanoparticles obtained by electric explosion of wire with different dispersion parameters were compared. Magnetoimpedance detection of stray magnetic fields of the obtained composites in the form of cylinders using a strip multilayer film element [FeNi/Cu]5/Cu/[FeNi/Cu]5 was carried out. It is shown that it is possible to determine the position of filled magnetic composites at different mass concentrations of magnetic micro- or nanoparticles with different parameters of dispersion of the ensemble using magnetoimpedance detection. Ключевые с

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Ratajczak, Filip, Bassam Jameel, Rafał Bielas e Arkadiusz Józefczak. "Ultrasound Control of Pickering Emulsion-Based Capsule Preparation". Sensors 24, n.º 17 (2 de setembro de 2024): 5710. http://dx.doi.org/10.3390/s24175710.

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Capsules with microparticle shells became of great interest due to their potential in many fields. Those capsules can be fabricated at high temperatures from particle-stabilized emulsions (Pickering emulsions) by sintering together particles that cover droplets. One of the problems with such an approach is accurately controlling whether particles are already sintered and creating the rigid capsule shell of a capsule. Here, we propose using a non-destructive ultrasound method for monitoring Pickering emulsion-based capsules prepared using heating under an alternating magnetic field. The polyethylene microparticles that were responsive to temperatures higher than 112 °C were used as droplet stabilizers together with iron oxide nanoparticles. During the coalescence of the droplets, facilitated by an external electric field, the ultrasonic attenuation increased, giving evidence that the ultrasound method detects structural changes in Pickering emulsions. The main change was the difference in the droplets’ size, which was also observed via optical microscopy. The attenuation of ultrasound increased even more when measured after magnetic heating for the same concentration of particle stabilizers. Simultaneously, the values of ultrasonic velocity did not exhibit similar variety. The results show that the values of the attenuation coefficient can be used for a quantitative evaluation of the capsule formation process.

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Yan, Fei, Wei Yang, Xiang Li, Hongmei Liu, Xiang Nan, Lisi Xie, Dongliang Zhou et al. "Erratum to “Magnetic Resonance Imaging of Atherosclerosis Using CD81-Targeted Microparticles of Iron Oxide in Mice”". BioMed Research International 2018 (18 de outubro de 2018): 1–2. http://dx.doi.org/10.1155/2018/8093438.

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Al Faraj, Achraf, Florence Gazeau, Claire Wilhelm, Cécile Devue, Coralie L. Guérin, Christine Péchoux, Valérie Paradis, Olivier Clément, Chantal M. Boulanger e Pierre-Emmanuel Rautou. "Endothelial Cell–derived Microparticles Loaded with Iron Oxide Nanoparticles: Feasibility of MR Imaging Monitoring in Mice". Radiology 263, n.º 1 (abril de 2012): 169–78. http://dx.doi.org/10.1148/radiol.11111329.

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Badhe, Ravindra V., Pradeep Kumar, Yahya E. Choonara, Thashree Marimuthu, Olufemi D. Akilo, Pierre P. D. Kondiah, Lisa C. du Toit e Viness Pillay. "Induction of creep crack morphology in iron oxide microparticles: An outcome of the common-ion effect". Materials Letters 188 (fevereiro de 2017): 417–22. http://dx.doi.org/10.1016/j.matlet.2016.11.072.

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Gordon, Andrew C., Robert J. Lewandowski, Riad Salem, Delbert E. Day, Reed A. Omary e Andrew C. Larson. "Localized Hyperthermia with Iron Oxide–Doped Yttrium Microparticles: Steps toward Image-Guided Thermoradiotherapy in Liver Cancer". Journal of Vascular and Interventional Radiology 25, n.º 3 (março de 2014): 397–404. http://dx.doi.org/10.1016/j.jvir.2013.10.022.

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McAteer, Martina A., Asim M. Akhtar, Constantin von zur Muhlen e Robin P. Choudhury. "An approach to molecular imaging of atherosclerosis, thrombosis, and vascular inflammation using microparticles of iron oxide". Atherosclerosis 209, n.º 1 (março de 2010): 18–27. http://dx.doi.org/10.1016/j.atherosclerosis.2009.10.009.

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Dinislamova, Olga A., Antonina V. Bugayova, Tatyana F. Shklyar, Alexander P. Safronov e Felix A. Blyakhman. "Echogenic Advantages of Ferrogels Filled with Magnetic Sub-Microparticles". Bioengineering 8, n.º 10 (11 de outubro de 2021): 140. http://dx.doi.org/10.3390/bioengineering8100140.

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Ultrasonic imaging of ferrogels (FGs) filled with magnetic nanoparticles does not reflect the inner structure of FGs due to the small size of particles. To determine whether larger particle size would improve the acoustic properties of FGs, biocompatible hydrogels filled with 100–400 nm iron oxide magnetic sub-microparticles with weight fraction up to 23.3% were synthesized and studied. Polymeric networks of synthesized FGs were comprised of chemically cross-linked polyacrylamide with interpenetrating physical network of natural polysaccharide—Guar or Xanthan. Cylindrical samples approximately 10 mm in height and 13 mm in diameter were immersed in a water bath and examined using medical ultrasound (8.5 MHz). The acoustic properties of FGs were characterized by the intensity of reflected echo signal. It was found that the echogenicity of sub-microparticles provides visualization not only of the outer geometry of the gel sample but of its inner structure as well. In particular, the echogenicity of FGs interior depended on the concentration of magnetic particles in the FGs network. The ultrasound monitoring of the shape, dimensions, and inner structure of FGs in the applied external magnetic field is demonstrated. It is especially valuable for the application of FGs in tissue engineering and regenerative medicine.

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Melnikov G. Yu., Lepalovskij V. N. e Kurlyandskaya G. V. "Magnetic impedance of film nanostructures for stray magnetic field evaluation of microparticles in magnetic composites". Technical Physics 92, n.º 2 (2022): 266. http://dx.doi.org/10.21883/tp.2022.02.52958.259-21.

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Longitudinal giant magnetoimpedance effect of [Fe21Ni79/Cu]5/Cu/[Fe21Ni79/Cu]5 film element was investigated depends on stray magnetic field of epoxy magnetic composite with 30% weight concentration of iron oxide magnetic microparticles. Configuration of an experiment was a model of thrombus detection in a blood vessel. Stray magnetic field was varied by movement of a magnetic composite above the element perpendicular to the long side. Composite was either magnetized or not to the state of remanence. As the magnetic composite approaches the GMI element, MI ratio curves are smoothed and shifted along the field axis and maximum value of the MI ratio decreases. Magnetic properties of magnetic composite and film element were investigated as well. Keywords: Magnetoimpedance effect, multilayered film nanostructures, composite materials, biodetection.

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