Magnetic NP Research Articles

A Synthetic Approach to Synthesize Furan‐2‐Carboxylate Derivatives by Using a Magnetic Sodium Aluminate Catalyst

AbstractA novel and efficient procedure has been developed to synthesize furan‐2‐carboxylate derivatives through a one‐pot condensation of chloroacetate derivatives, 1,3‐diketones, and chloroform in the presence of magnetic sodium aluminate 40 wt. % (Aluminate NP‐40). The synthesized heterogeneous catalyst can be easily recovered from the reaction mixture by applying an external magnetic field. Magnetic aluminate NP catalysts provide a sustainable, environmentally friendly, and cost‐effective method for synthesizing furan‐2‐carboxylate derivatives. Additionally, the catalyst is stable and can be reused multiple times without losing its catalytic properties. High product yields in a short experimental time and easy workup are other advantages of the present method. All synthesized compounds were characterized by NMR spectroscopy.

Poly(lactic-co-glycolide) based biodegradable electrically and magnetically active microenvironments for tissue regeneration applications

Polymer scaffolds are playing an increasing role in tissue engineering (TE), although there is still a need to improve their biomimicry of cellular microenvironments, by having smart scaffolds with an active response, which can improve tissue regeneration.This work reports on the novel combination of poly(lactic-co-glycolide) (PLGA) with the ionic liquid (IL) choline bis(trifluoromethylsulfonyl)imide ([Chol][TFSI]) or with iron oxide nanoparticles (Fe3O4, NP) in order to achieve biodegradable scaffolds with electroactive and magnetoactive response, respectively.The composites were processed into fiber and film morphologies. PLGA + IL fibers present diameters between 1.92 and 3.26 µm, decreased mechanical stiffness and elongation at yield with respect to the pristine polymer, and some fiber concentrations are not biocompatible. PLGA + IL films present a mean roughness 6.58 nm, increased mechanical stiffness with respect to the pristine polymer and decreased elongation at yield. The inclusion of IL increased the electrical conductivity of the polymer by 4 orders or magnitude. The diameter of PLGA + Fe3O4 fibers ranged from 0.62 to 1.36 µm, show an effective magnetic NP content yield between 52 and 78%, decreased stiffness and increased elongation at yield. PLGA + Fe3O4 films show a mean roughness of 5.07 nm, effective NP content yield between 77 and 97%, increased stiffness and elongation at yield.Cytotoxicity assays indicate that the PLGA + Fe3O4 materials are suitable for biomedical applications, independently of the filler content and morphology, whereas the IL containing samples are non-cytotoxic only in film morphology up to 5% wt. IL content.Finally, it is demonstrated that dynamic magneto mechanical stimulation of the PLGA + Fe3O4 samples allows the acceleration of the degradation rate of the samples.

Recent Breakthroughs and Advancements in NOx and SOx Reduction Using Nanomaterials-Based Technologies: A State-of-the-Art Review.

Nitrogen and sulpher oxides (NOx, SOx) have become a global issue in recent years due to the fastest industrialization and urbanization. Numerous techniques are used to treat the harmful exhaust emissions, including dry, traditional wet and hybrid wet-scrubbing techniques. However, several difficulties, including high-energy requirement, limited scrubbing-liquid regeneration, formation of secondary pollutants and low efficiency, limit their industrial utilization. Regardless, the hybrid wet-scrubbing technology is gaining popularity due to low-costs, less-energy consumption and high-efficiency removal of air pollutants. The removal/reduction of NOx and SOx from the atmosphere has been the subject of several reviews in recent years. The goal of this review article is to help scientists grasp the fundamental ideas and requirements before using it commercially. This review paper emphasizes the use of green and electron-rich donors, new breakthroughs, reducing GHG emissions, and improved NOx and SOx removal catalytic systems, including selective/non-catalytic reduction (SCR/SNCR) and other techniques (functionalization by magnetic nanoparticles; NP, etc.,). It also explains that various wet-scrubbing techniques, synthesis of solid iron-oxide such as magnetic (Fe3O4) NP are receiving more interest from researchers due to the wide range of its application in numerous fields. In addition, EDTA coating on Fe3O4 NP is widely used due to its high stability over a wide pH range and solid catalytic systems. As a result, the Fe3O4@EDTA-Fe catalyst is projected to be an optimal catalyst in terms of stability, synergistic efficiency, and reusability. Finally, this review paper discusses the current of a heterogeneous catalytic system for environmental remedies and sustainable approaches.

Study the Effect of Laser Wavelength on Polymeric Metallic Nanocarrier Synthesis for Curcumin Delivery in Prostate Cancer Therapy: In Vitro Study

Drug delivery using nanocarriers is recommended to decrease the drug amount. To improve the different therapeutic characteristics of curcumin (CU) such as solubility, bioavailability, maintenance endorsement, and make it a promising, successful antitumor drug used for prostate cancer treatment. It was introduced to folate decorated chitosan (CS) coated Fe@Au NPs (FA-CU-CS-Fe@Au NPs). Fe@Au nanoparticle contains magnetic Fe NP’s core with a fine layer of Au NP’s synthesized using the method Pulsed, Laser, Ablation in Liquid (PLAL). These Fe@Au NP’s characterized by UV-Visible Spectrophotometer, High-Resolution, Transmission Electron Microscopy, (HRTEM), and Field Emission Scanning, Electron, Microscopy (FESEM). The smallest nanosize and the best result was obtained at different laser wavelength (532, 1064) nm. The mean size gained of Fe@Au NPs were (67.65, 77.88) nm. Obtained results exhibited that the laser wavelength plays a key role in the size, and dispersity of Fe@Au NPs. CU loaded FA-CS-Fe@Au NPs MTT assay on human prostate cancer cell line (PC3) proved that CU cytotoxicity can improve when they are loaded on (FA-CS-Fe@Au NPs) when comparing it with free CU.

Bio-inspired synthesis of palladium nanoparticles fabricated magnetic Fe3O4 nanocomposite over Fritillaria imperialis flower extract as an efficient recyclable catalyst for the reduction of nitroarenes

This current research is based on a bio-inspired procedure for the synthesis of biomolecule functionalized hybrid magnetic nanocomposite with the Fe3O4 NPs at core and Pd NPs at outer shell. The central idea was the initial modification of magnetic NP by the phytochemicals from Fritillaria imperialis flower extract, which was further exploited in the green reduction of Pd2+ ions into Pd NPs, in situ. The flower extract also acted as a capping agent for the obtained Pd/Fe3O4 composite without the need of additional toxic reagents. The as-synthesized Fe3O4@Fritillaria/Pd nanocomposite was methodically characterized over different physicochemical measures like FT-IR, ICP-AES, FESEM, EDX, TEM, XPS and VSM analysis. Thereafter, its catalytic potential was evaluated in the reduction of various nitrobenzenes to arylamines applying hydrazine hydrate as reductant in ethanol/water (1:2) medium under mild conditions. Furthermore, the nanocatalyst was retrieved using a bar magnet and recycled several times without considerable leaching or loss of activity. This green, bio-inspired ligand-free protocol has remarkable advantages like environmental friendliness, high yields, easy workup and reusability of the catalyst.

Current role of nanoparticles in the treatment of lung cancer

Worldwide, lung cancer is one of the leading causes of cancer death. Nevertheless, new therapeutic agents have been developed to treat lung cancer that could change this mortality-rate. Interestingly, incredible advances have occurred in recent years in the development and application of nanotechnology in the detection, diagnosis, and treatment of lung cancer. Nanoparticles (NPs) have the ability to incorporate multiple drugs and targeting agents and therefore lead to an improved bioavailability, sustained delivery, solubility, and intestinal absorption. This review briefly summarizes the latest innovations in therapeutic nanomedicine in lung cancer with examples on magnetic, lipid, and polymer NP. Emphasis will be placed on future studies and ongoing clinical trials in this field.

Multifunctional magnetic CoFe2O4 nanoparticles for the photocatalytic discoloration of aqueous methyl violet dye and energy storage applications

A magnetic visible light active CoFe2O4 nano photocatalyst was prepared by co-precipitation technique and its catalytic performance was evaluated by discoloration of methyl violet (MV) dye. The optical, magnetic, and morphological properties of the annealed CoFe2O4 photocatalyst were characterized by UV–Vis, VSM, FE-SEM, EDX, TEM, and FT-IR spectroscopic techniques. Further, the calcined CoFe2O4 nanoparticles were used as heterogeneous catalyst in H2O2 assisted discoloration of MV dye under visible light irradiation, in which 71% color removal was achieved within 120 min. The photodiscoloration of aqueous solution of MV dye was found to follow pseudo-first order kinetics. The supercapacitor measurements were also accomplished in 1 M aqueous KOH electrolyte for the sample CoFe2O4 NP’s calcined at 350 °C. The as-prepared CoFe2O4 electrode displayed significantly improved specific capacity value (1233 F/g at the scan rate of 5 mVs−1). In addition, capacity retention of CoFe2O4was found to be with 90% upto 5000 GCD cycles. Thus, the magnetic CoFe2O4 NP’s were demonstrated as an efficient photocatalyst as well as suitable electrode material for energy storage application.

Chemiluminescence activity of neutrophil granulocytes under the influence of magnetic nanoparticles of ferrihydrite (<i>in vitro</i>)

The article presents the results of studying and evaluating the impact of magnetic nanoparticles of ferrihydrite on neutrophil granulocytes in human blood ( in vitro ) in order to determine their bio compatibility and eco toxicity. The subject soft here search were blood neutrophil granulocytes of 29 conditionally-healthy donors of blood, as well as magnetic nanoparticles of ferrihydrite (NP), the preparation dose in minimum concentration reached 25 mg, in maximum concentration it reached 50 mg per 10 6 cells/ml. We implemented the sol of magnetic NP, obtained by biogenic synthesis in International Scientific Centre for Studying Extreme States of an Organism. Functional activity of blood neutrophil granulocytes has been determined by luminol-dependent chemiluminescence. Magnetic NP were introduced into pilot samples straight before chemiluminescent analysis, and also after the incubation with in 30 minutes under 37 °С entigrade. As a result of thee stimation of the early response of neutrophil granulocytes to the influence of minimum concentration of magnetic NP in vitro we found statistically true decrease of the intensity (1.6 times), the area under the curve (2.1 times) in zymosan-induced chemiluminescent response, the activation index (2.3 times). When evaluating the late response of neutrophil granulocytes to the influence of maximum concentration of magnetic NP in vitro we have found statistically true lowering of the time of reaching the peak (10 times) of spontaneous chemiluminescence. More over we marked consider able lowering of maximum intensity 6 times and the reduction of the area under the curve of zymosan-induced chemiluminescence 5.6 times under the influence of magnetic NP under the lowering of activation index 3.7 times. The authors determined that magnetic NP were intensively decreasing the functional activity of neutrophil granulocytes. The intensity of the impact is higher under the preliminary incubation of the cells with magnetic NP. At the same time, short effect of magnetic NP to neutrophil granulocytes can be a modulating one and depends on the initial level of cell reactivity. We revealed that magnetic NP influence concerns only activated cells.

Encapsulation of HRP Enzyme onto a Magnetic Fe3O4 Np–PMMA Film via Casting with Sustainable Biocatalytic Activity

Horseradish peroxidase (HRP) enzyme was effectively encapsulated onto an Fe3O4 nanoparticle–polymethyl methacrylate (PMMA) film via the casting method. The HRP was immobilized on the 0.5% Fe3O4Np–PMMA film and characterized by Fourier transform infrared spectroscopy and field emission scanning electron microscopy. Moreover, the reusability, thermal stability, optimum pH, optimum temperature, the influence of metal ions, and the effects of detergent and organic solvent were investigated. After optimizing the immobilization conditions, the highest efficiency of the immobilized enzyme was 88.4% using 0.5% Fe3O4Np–PMMA. The reusability of the immobilized HRP activity was 78.5% of its initial activity after being repeatedly used for 10 cycles. When comparing the free and immobilized forms of the HRP enzyme, changes in the optimum temperature and optimum pH from 30 to 40 °C and 7.0 to 7.5, respectively, were observed. The Km and Vmax for the immobilized HRP were estimated to be 41 mM, 0.89 U/mL for guaiacol and 5.84 mM, 0.66 U/mL for H2O2, respectively. The high stability of the immobilized HRP enzyme was obtained using metal ions, a high urea concentration, isopropanol, and Triton X-100. In conclusion, the applicability of immobilized HRP involves the removal of phenol in the presence of hydrogen peroxide, therefore, it could be a potential catalyst for the removal of wastewater aromatic pollutants.

Magnetic nanoparticle recovery device (MagNERD) enables application of iron oxide nanoparticles for water treatment

An optimized permanent magnetic nanoparticle recovery device (i.e., the MagNERD) was developed and operated to separate, capture, and reuse superparamagnetic Fe3O4 from treated water in-line under continuous flow conditions. Experimental data and computational modeling demonstrate how the MagNERD’s efficiency to recover nanoparticles depends upon reactor configuration, including the integration of stainless-steel wool around permanent magnets, hydraulic flow conditions, and magnetic NP uptake. The MagNERD efficiently removes Fe3O4 in the form of a nanopowder, up to > 95% at high concentrations (500 ppm), under scalable and process-relevant flow rates (1 L/min through a 1.11-L MagNERD reactor), and in varying water matrices (e.g., ultrapure water, brackish water). The captured nanoparticles were recoverable from the device using a simple hydraulic backwashing protocol. Additionally, the MagNERD removed ≥ 94% of arsenic-bound Fe3O4, after contacting As-containing simulated drinking water with the nanopowder. The MagNERD emerges as an efficient, versatile, and robust system that will enable the use of magnetic nanoparticles in larger scale water treatment applications.

Biological Properties of the Aggregated Form of Chitosan Magnetic Nanoparticle.

Chitosan-coated iron oxide nanoparticles (Chi-NP) have gained attention because of their biocompatibility, biodegradability, low toxicity and targetability under magnetic field. In this study, we investigated various biological properties of Chi-NP. Chi-NP was prepared by mixing magnetic NP with chitosan FL-80. Particle size was determined by scanning and transmission electron microscopes, cell viability by MTT assay, cell cycle distribution by cell sorter, synergism with anticancer drugs by combination index, PGE2 production in human gingival fibroblast was assayed by ELISA. The synthetic process of Chi-NP from FL-80 and magnetic NP increased the affinity to cells, up to the level attained by nanofibers. Upon contact with the culture medium, Chi-NP instantly formed aggregates and interfered with intracellular uptake. Aggregated Chi-NP did not show cytotoxicity, synergism with anticancer drugs, induce apoptosis (accumulation of subG1 cell population), protect the cells from X-ray-induced damage, nor affected both basal and IL-1β-induced PGE2 production. Chi-NP is biologically inert and shows high affinity to cells, further confirming its superiority as a scaffold for drug delivery.

Novel electro-magnetophoretic separation method for the highly sensitive detection of analytes

We present a method to improve the detection limits of assays based on magnetic particles based on electro-magnetophoretic separation. It can be used with existing protocols to lower their detection limits by removing the excess of magnetic NP.

Simultaneous determination of opioid drugs in urine with high‐performance liquid chromatography–ultraviolet after supramolecular based magnetic NP solid‐phase extraction

A simple and rapid extraction/preconcentration procedure using supramolecular based magnetic nanoparticle (MNP) solid-phase extraction method by sodium dodecyl sulphate (SDS)-coated MNPs has been developed for both removal and preconcentration of three important opioid drugs named morphine, codeine and methadone before their high-performance liquid chromatography–ultraviolet determination. To get insight configuration of SDS molecules on the surface of the MNPs, zeta potential measurements were performed in different SDS (mg)/mg of MNPs ratios. Parameters affecting the extraction and preconcentration efficiency of the opioids were optimised as recovery by one variable at-a-time methodology and the obtained recoveries were 91, 94 and 98% for morphine, codeine and methadone, respectively. Under optimum conditions (such as pH = 3.5; adsorbent amount = 60 mg; eluent solvent volume = 2 ml of acetonitrile, sample volume = 200 ml etc.), the method was linear in the range of 1–200 ng ml−1 with enrichment factors (EFs) of 91, 94 and 98 for morphine, codeine and methadone, respectively, and the limits of detection were <0.27 ng ml−1. Finally, the proposed method was successfully applied for both removal and trace determination of the targeted drugs in urine samples.

Preparation of novel magnetic polyurethane foam nanocomposites by using core-shell nanoparticles

Abstract Iron oxide magnetic nanoparticles (NP's) converted to the core- shell structres by reacting with by n-(2-aminoethyl)-3-aminopropyl trimethoxysilane (AEAP) incorporated in polyurethane flexible (PUF) foam formulations. Fourier transform spectra, thermal gravimetric analysis, scanning electron images, thermo-mechanical analysis and magnetic properties of the prepared nanocomposites were studied. Obtained data shown that by the increasing of the amine modified magnetic iron oxide NP's up to 3% in the polymer matrix, thermal and magnetic properties improved in comparison with pristine foams. In addition, due to the presence of functional groups on the magnetic NP's surface, hard phases formation decrease in the bulk polymer and cause decreasing of glass transition temperature.

Synthesis of Water Dispersible and Catalytically Active Gold-Decorated Cobalt Ferrite Nanoparticles.

Hetero-nanoparticles represent an important family of composite nanomaterials that in the past years are attracting ever-growing interest. Here, we report a new strategy for the synthesis of water dispersible cobalt ferrite nanoparticles (CoxFe3-xO4 NPs) decorated with ultrasmall (2-3 nm) gold nanoparticles (Au NPs). The synthetic procedure is based on the use of 2,3-meso-dimercaptosuccinic acid (DMSA), which plays a double role. First, it transfers cobalt ferrite NPs from the organic phase to aqueous media. Second, the DMSA reductive power promotes the in situ nucleation of gold NPs in proximity of the magnetic NP surface. Following this procedure, we achieved a water dispersible nanosystem (CoxFe3-xO4-DMSA-Au NPs) which combines the cobalt ferrite magnetic properties with the catalytic features of ultrasmall Au NPs. We showed that CoxFe3-xO4-DMSA-Au NPs act as an efficient nanocatalyst to reduce 4-nitrophenol to 4-aminophenol and that they can be magnetically recovered and recycled. It is noteworthy that such nanosystem is more catalytically active than Au NPs with equal size. Finally, a complete structural and chemical characterization of the hetero-NPs is provided.

Folate-decorated anticancer drug and magnetic nanoparticles encapsulated polymeric carrier for liver cancer therapeutics

Nanoparticulate system with theranostic applications has attracted significant attention in cancer therapeutics. In the present study, we have developed a novel composite PLGA NP co-encapsulated with anticancer drug (sorafenib) and magnetic NP (SPION). We have successfully developed nanosized folate-conjugated PEGylated PLGA nanoparticles (SRF/FA–PEG–PLGA NP) with both anticancer and magnetic resonance property. We have showed that FA-conjugated NP exhibits sustained drug release and enhanced cellular uptake in BEL7402 cancer cells. The targeted NP effectively suppressed the tumor cell proliferation and has improved the anticancer efficacy than that of free drug or non-targeted one. Additionally, enhanced MRI properties demonstrate this formulation has good imaging agent characteristics. Finally, SRF/FA–PEG–PLGA NP effectively inhibited the colony forming ability indicating its superior anticancer effect. Together, these multifunctional nanoparticles would be most ideal to improve the therapeutic response in cancer and holds great potential to be a part of future nanomedicine. Our unique approach could be extended for multiple biomedical applications.

SERS as a valuable tool for detection and treatment follow-up of fungal infection in mice lungs: use of Amphotericin B and its nanoencapsulation onto magnetic nanoparticles

This study reports on the use of surface-enhanced Raman scattering (SERS) detection and follow-up treatment of Paracoccidioides brasiliensis (Pb) infection in lung's mice. We also reports on the introduction of a new drug carrier system [nanoparticle-Amphotericin B (NP-AmB)], comprising magnetic NP surface functionalized with AmB, and its use in the treatment of infected and non-infected mice. SERS was successfully used to monitor the efficacy of the mice's treatment using the new NP-AmB, while free AmB (F-AmB), considering the current drug of choice for treatment of Pb infection, was also used and taken as reference for the treatment. We found SERS provides a robust platform to discriminate infected lung tissues from non-infected ones based on fingerprints assessed via SERS spectra and focused on the redox state of heme groups present in the collected biological material. Finally, SERS data reported in this study indicated that the new NP-AmB formulation provides similar clinical response as the F-AmB, although incorporating 40% lower content of AmB and administered in a time interval schedule (every 72 h) three times longer than F-AmB (every 24 h). Copyright © 2013 John Wiley & Sons, Ltd.

Polyelectrolyte coating of iron oxide nanoparticles for MRI-based cell tracking

Iron oxide-based magnetic nanoparticles (MNPs) offer unique properties for cell tracking by magnetic resonance imaging (MRI) in cellular immunotherapy. In this study, we investigated the uptake of chemically engineered NPs into antigen-presenting dendritic cells (DCs). DCs are expected to perceive MNPs as foreign antigens, thus exhibiting the capability to immunologically sense MNP surface chemistry. To systematically evaluate cellular uptake and T2/T2⁎ MR imaging properties of MNPs, we synthesized polymer-based MNPs by employing layer-by-layer (LbL) technology. Thereby, we achieved modification of particle shell parameters, such as size, surface charge, and chemistry. We found that subcellular packaging of MNPs rather than MNP content in DCs influences MR imaging quality. Increased local intracellular electron density as inferred from transmission electron microscopy (TEM) strongly correlated with enhanced contrast in MRI. Thus, LbL-tailoring of MNP shells using polyelectrolytes that impact on uptake and subcellular localization can be used for modulating MR imaging properties. From the Clinical EditorIn this study, layer-by-layer tailoring of magnetic NP shells was performed using polyelectrolytes to improve uptake by dendritic cells for cell-specific MR imaging. The authors conclude that polyelectrolyte modified NP-s can be used for modulating improving MR imaging quality by increasing subcellular localization.

Anion vacancy-driven magnetism in incipient ferroelectric SrTiO3 and KTaO3 nanoparticles

We predict that undoped nanoparticles (size ≤ 10–100 nm) of incipient ferroelectrics without any magnetic ions can become ferromagnetic even at room temperatures due to the inherent presence of a new type of magnetic defects with spin S = 1, namely oxygen vacancies, where the magnetic triplet state is the ground state in the vicinity of the surface (magnetic shell), while the nonmagnetic singlet is the ground state in the bulk material (nonmagnetic core). In particular, for a particle radii R less than the critical radius Rc(T) ferromagnetic long-range order appears in a shell region of thickness 5–50 nm once the concentration of magnetic defects N exceeds the magnetic percolation threshold Np. At vacancy concentrations N &amp;lt; Np and radii R &amp;lt; Rc(T), short-range ferromagnetic order and consequently a spin glass state may appear. For particle radii R &amp;gt; Rc(T), only the paramagnetic phase is possible.

Kondo behavior in superconductingNpPd5Al2

The unconventional superconductor ${\text{NpPd}}_{5}{\text{Al}}_{2}$, crystallizing in the tetragonal ${\text{ZrNi}}_{2}{\text{Al}}_{5}$-type structure, was studied by means of $^{237}\text{N}\text{p}$ M\ossbauer spectroscopy, heat capacity, electrical resistivity, magnetoresistivity, and thermoelectric power measurements. The superconductivity is clearly observed below ${T}_{c}=5\text{ }\text{K}$. The M\ossbauer studies confirm the absence of ordered magnetic Np moments in both the superconducting and normal phases. The value of the isomer shift suggests that the $5f$-electron count is close to ${n}_{5f}=4$, in agreement with electron band structure calculations. Above ${T}_{c}$ the electronic specific heat, the magnetic contribution to the electrical resistivity, the magnetoresistivity, and the Seebeck coefficient are governed by the interplay of Kondo and crystal-field effects. The Seebeck coefficient, negative in the whole temperature range, indicates electronlike conductivity. This perfectly agrees with the Hall effect data as well as with theoretical predictions.