Mixture Of Iron Oxide Nanoparticles Research Articles

Carbon shell derived from bottle waste PET on α-Fe2O3/Fe3O4 heterostructure core as synergetic Fenton-like catalyst for degradation of antibiotics

In this work, two approaches to environmental sustainability have been followed including the synthesis of an efficient and easily recyclable catalyst for Fenton-like degradation of antibiotics from water, and the upcycling of waste polyethylene terephthalate (PET) into the value-added product through a feasible procedure. For this purpose, the Fe2O3/Fe3O4 mixture coated by the carbon layer derived from the bottle waste PET was synthesized for boosting the Fe3+/Fe2+ cycle in the Fenton-like reaction. The FeCl3 can act as a catalyst for graphitization process and also the precursor of metal oxide nanoparticles. The catalytic efficiency was evaluated for the degradation reaction of amoxicillin and azithromycin antibiotics. Complete conversion of amoxicillin and azithromycin (15 mg/L) was observed in the presence of 5 µL of H2O2, at pH=3 for 30 min. Also, the mineralization of amoxicillin and azithromycin was evaluated by TOC analysis, which was obtained as 77 and 89 %, respectively. The high activity of the catalyst can be attributed to the presence of a mixture of iron oxide nanoparticles for the catalysis of Fenton-like reactions and activation of H2O2, as well as the coating of nanoparticles with a carbon layer to stabilize and prevent metal leakage and contamination of the mixture. In addition, due to the good electrical conductivity of carbon layer, it can act as electron donors to enhance Fe3+ reduction.

Phyto-interactive impact of green synthesized iron oxide nanoparticles and Rhizobium pusense on morpho-physiological and yield components of greengram

The iron oxide nanoparticles (IONPs) prepared by green synthesis method using Syzigium cumini leaf extract was characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), and transmission electron microscopy (TEM). The XRD confirmed the crystalline structure of green synthesized NPs measuring around 33 nm while SEM revealed its nearly spherical shape. Rhizobium species recovered from greengram nodules, identified by 16s rRNA gene sequencing as Rhizobium pusense produced 30% more exopolysaccharides (EPS) in basal medium treated with 1000 μg IONPs/ml. Compositional variation in EPS was observed by Fourier-transform infrared spectroscopy (FTIR). There was no reduction in rhizobial viability and no damage to bacterial membrane was observed under SEM and confocal laser scanning microscopy (CLSM), respectively. Effects of IONPs and R. pusense, used alone and in combination on the growth and development of greengram plants varied considerably. Plants grown with IONPs and R. pusence, used alone and in combination, showed a significant increase in seed germination rate, length and dry biomass of plant organs and seed components compared to controls. The IONPs in the presence of rhizobial strain further increased seed germination, plant growth, seed protein and pigments. Greater protein content (442 mg/g) was observed in seeds at 250 mg/kg of IONPs compared to control. Plants raised with mixture of IONPs plus R. pusense had maximum chlorophyll content (39.2 mg/g FW) while proline content decreased by 53% relative to controls. This study confirms that the green synthesis of IONPs from S. cumini leaf possess useful plant growth promoting effects and could be developed as a nano-biofertilizer for optimizing legume production.

Synthesis and application of hematite nanoparticles for acid mine drainage treatment

In this paper, the synthesis of pure hematite nanoparticles, magnetic properties and its removal capacity of metal cations from acid mine drainage are well described. Initially, mixtures of iron oxide nanoparticles were synthesised using hydrated ferric chloride and ferrous sulphate salt solution by co-precipitation method and converted to hematite via calcination at 500 °C. The synthesised hematite nanoparticles have shown superparamagnetic character with saturation magnetisation of 5.6 emu g−1. Treatment of partially aerated acid mine drainage in the presence of 0.85 g L−1 of synthesised hematite resulted in complete removal of Al, Mg, Mn and Fe while for Zn and Ni over 80% and Ca and Na in between 47 and 72% removals. The sludge generated from the treated acid mine drainage was also characterised by relevant analytical instruments. Overall, the non-toxicity, stability and high metal removal capacity of hematite nanoparticles is promising for the future application in large-scale acid mine drainage treatment.

Self-assembly of a binary mixture of iron oxide nanoparticles in Langmuir film: X-ray scattering study

In present study we exploited Langmuir technique to produce self-assembled arrays composed of monodisperse iron oxide nanoparticles 10 nm and 20 nm in diameter and of their binary mixture. A combination of in-situ X-ray reflectometry and Grazing-incident small-Angle X-ray scattering was used to obtain in-plane and out-of-plane structure of the arrays directly on the water surface. Surface pressure isotherms and X-ray reflectometry analysis showed that monodisperse 10 nm nanoparticles form a highly ordered monolayer, while 20 nm particles pack in three-dimensional clusters with a short-range (nearest-neighbor) correlations between the particles. In a binary mixture of 10 nm and 20 nm nanoparticles composed in proportion 3:1 the self-assembly process results in a structure where the monolayer of 10 nm particles is perturbed by the larger particles. Non-trivial mixing causes an enlargement of interparticle distance but keeps the symmetry of two-dimensional lattice of smaller nanoparticles. Estimation of the acting interactions and micromagnetic simulation suggest the optimal formation for monodisperse and binary ensembles.

Effects of Iron Oxide Nanoparticle Labeling on Human Endothelial Cells

Iron oxide nanoparticles (INOPS) are a potential contrast agent for magnetic resonance (MR) tracking of transplanted endothelial cells. The objective of this study was to examine the effect of INOPS labeling on endothelial cells. The mixture of INOPS and poly-l-lysine (PLL) was used to label human endothelial cells. Labeling efficiency was examined by Prussian blue staining, transmission electron microscopy, and atomic absorption spectrometry. The effect of iron oxide concentration on cell viability and proliferation were determined. The correlation of reactive oxygen species (ROS) and apoptosis was also examined. In vitro MRI scanning was carried out using a 1.5T MR system. INOPS-PLL could be readily taken up by endothelial cells and subsequently induce MRI signal intensity changes. However, higher labeling concentration (>50 µg/ml) and longer incubation (48 h) can affect cell viability and proliferation. Mitochondrial damage, apoptosis, and autolysosmes were observed under high INOPS-PLL concentrations, which were correlated to ROS production. INOPS-PLL nanoparticles can be used to label transplanted endothelial cells. However, high concentration of INOPS can impair cell viability, possibly through ROS-mediated apoptosis and autophagy.

Synthesis of Pd/α-Fe 2O 3 nanocomposites for catalytic CO oxidation

Iron oxide and metal doped iron oxide nanocomposites have found attractive and versatile applications in many research areas such as catalysts, sensors, and biomedicine. This work reports a surfactant-free hydrolysis approach for the synthesis of hematite (α-Fe 2O 3) and Pd doped α-Fe 2O 3 nanoparticles with low-temperature catalytic activity. By this method, iron oxide rod-like nanoparticles were achieved by hydrolysis of ferric chloride salt with dilute HCl at a temperature of 100 °C. The Pd/iron oxide nanocomposites were obtained by adding citric acid into a mixture of iron oxide nanoparticles and palladium precursor (Pd(CH 3CN) 2Cl 2) under a reflux heating at 90 °C for 2 h. This method is featured as no use of any surfactants and templates, and no requirement of high-temperature thermal decomposition that are usually required for shape/size control in polar or nonpolar solvents. More importantly, it was found that the Pd/α-Fe 2O 3 nanocomposites exhibited high low-temperature catalytic activity in carbon monoxide (CO) oxidation.

MAGNETIC NANOPARTICLE LABELING OF CULTURED CANCER CELL LINE WITHOUT TRANSFECTION AGENT

Magnetic nanoparticle (MNP) labeling of stem cell has been proved its efficacy for cell trafficking. Most of the labeling technique requires mixture of iron oxide nanoparticles and transfection agent. Stem cells with ionic MNP without the aid of transfection agent were labeled previously. The possibility of high efficiency labeling of cultured cancer cell, HeLa cell, by using ionic MNP is proposed. The labeled cell morphology was observed and the intracellular iron content was determined by spectrophotometry. The cell character change was evaluated by flow cytometry where front scattering count and side scattering count (SSC) were recorded. The imaging ability of the labeling method was determined by T2 weighted magnetic resonance (MR) imaging. Labeled MNPs were accumulated at cytoplasm is observed and the iron content of labeled cell could reach 27 pg/cell. There is no cell diameter change but the cell granularity increased according to SSC data from flow cytometry. Under clinical 1.5T MR imaging, we could detect labeled cells easily were detected at the cell number of 1 × 105. It is concluded that labeling of cancer cell with ionic MNPs without transfection agent is an efficient labeling method which will provide non-invasive imaging method for monitoring cancer behavior.