Iron Oxide Nanoparticles Research Articles

Aerobic Oxidation of Alcohols and Olefins Using Ru NPs Decorated on Functionalized PNIPAM Grafted Magnetic Nanoparticles

ABSTRACTA thermo‐responsive ruthenium catalyst was produced by immobilizing poly(N‐isopropyl acrylamide) on the silica surface coated iron oxide nanoparticles (Fe3O4@Si). After being exposed to ethylenediamine, the amino‐modified support (Fe3O4@Si‐PNIPAM‐NH2) was produced, and Fe3O4@Si‐PNIPAM‐NH2‐EDTA was made in the ensuing reaction with EDTA (ethylenediaminetetraacetic acid). Ru NPs were introduced to the modified magnetic support to create a well‐organized heterogeneous catalytic system with several advantages, such as enabling catalyst recycling and simple separation. This new catalyst was characterized by means of various techniques, including TGA, ICP, FT‐IR, DLS, TEM, SEM, EDX, VSM, XRD, CHN, and XPS. In the presence of H2O2 or air alone, this catalyst showed a significant effect in the oxidation of various alcohols to the corresponding aldehydes or ketones. Furthermore, the catalyst exhibited outstanding capacity in the aerobic oxidation of olefines to the carbonyl or oxirane counterparts. A main aspect of this catalytic system is the reusability of the catalyst at least eight times in consecutive runs without causing any discernible loss of activity, structural change, or leaching.

Precise Methylation Detection of Tumor Suppressor Gene Promoters by Magnetic Enrichment and Nano Silver Adduct–Promoted Surface‐Enhanced Raman Scattering

AbstractNoninvasive liquid biopsies can be used for early tumor diagnosis by identifying the methylation level of the tumor suppressor genes (TSGs)—a reliable index for cancer evaluation. However, identifying trace circulating genes from specimens remains challenging. This work introduces a novel method that combines magnetic isolation and surface‐enhanced Raman scattering (SERS) to concentrate and detect the methylated TSG promotors. A superparamagnetic iron oxide nanoparticle modified with streptavidin is prepared as a universal magnetic bead. Biotin‐terminated probe single‐strand DNA (ssDNA) is immobilized on the magnetic beads through biotin–streptavidin bioconjugation. Artificial target ssDNA fragments with various methylation levels are applied as a promoter gene model. Concentrated double‐strand DNA (dsDNA) is produced by a hybridizing probe and target ssDNA on magnetic nanobeads, as well as an additional magnetic isolation process. The well‐prepared DNA adduct, which consists of 3 nm cisplatin‐modified Ag nanoclusters, can specifically bind with guanine‐cytosine base pairs of dsDNA. Ag‐nanoparticle‐induced localized SERS amplified signals of 5‐methylcytosine (5‐mC) from the dsDNA in Raman spectra, enabling accurate methylation level measurement in mixtures of 0–1 µm methylated DNA, with a detection limit of 0.05 µm. This method shows promise for enabling the methylation level evaluation of various TSGs and promoters in early cancer liquid biopsies.

Comprehensive Analysis of the Potential Toxicity of Magnetic Iron Oxide Nanoparticles for Medical Applications: Cellular Mechanisms and Systemic Effects

Owing to recent advancements in nanotechnology, magnetic iron oxide nanoparticles (MNPs), particularly magnetite (Fe3O4) and maghemite (γ-Fe2O3), are currently widely employed in the field of medicine. These MNPs, characterized by their large specific surface area, potential for diverse functionalization, and magnetic properties, have found application in various medical domains, including tumor imaging (MRI), radiolabelling, internal radiotherapy, hyperthermia, gene therapy, drug delivery, and theranostics. However, ensuring the non-toxicity of MNPs when employed in medical practices is paramount. Thus, ongoing research endeavors are essential to comprehensively understand and address potential toxicological implications associated with their usage. This review aims to present the latest research and findings on assessing the potential toxicity of magnetic nanoparticles. It meticulously delineates the primary mechanisms of MNP toxicity at the cellular level, encompassing oxidative stress, genotoxic effects, disruption of the cytoskeleton, cell membrane perturbation, alterations in the cell cycle, dysregulation of gene expression, inflammatory response, disturbance in ion homeostasis, and interference with cell migration and mobility. Furthermore, the review expounds upon the potential impact of MNPs on various organs and systems, including the brain and nervous system, heart and circulatory system, liver, spleen, lymph nodes, skin, urinary, and reproductive systems.

The Long-Term Impact of Polysaccharide-Coated Iron Oxide Nanoparticles on Inflammatory-Stressed Mice

The Long-Term Impact of Polysaccharide-Coated Iron Oxide Nanoparticles on Inflammatory-Stressed Mice

Advanced Nanomaterials for Cancer Therapy: Gold, Silver, and Iron Oxide Nanoparticles in Oncological Applications.

Cancer remains one of the most challenging health issues globally, demanding innovative therapeutic approaches for effective treatment. Nanoparticles, particularly those composed of gold, silver, and iron oxide, have emerged as promising candidates for changing cancer therapy. This comprehensive review demonstrates the landscape of nanoparticle-based oncological interventions, focusing on the remarkable advancements and therapeutic potentials of gold, silver, and iron oxide nanoparticles. Gold nanoparticles have garnered significant attention for their exceptional biocompatibility, tunable surface chemistry, and distinctive optical properties, rendering them ideal candidates for various cancer diagnostic and therapeutic strategies. Silver nanoparticles, renowned for their antimicrobial properties, exhibit remarkable potential in cancer therapy through multiple mechanisms, including apoptosis induction, angiogenesis inhibition, and drug delivery enhancement. With their magnetic properties and biocompatibility, iron oxide nanoparticles offer unique cancer diagnosis and targeted therapy opportunities. This review critically examines the recent advancements in the synthesis, functionalization, and biomedical applications of these nanoparticles in cancer therapy. Moreover, the challenges are discussed, including toxicity concerns, immunogenicity, and translational barriers, and ongoing efforts to overcome these hurdles are highlighted. Finally, insights into the future directions of nanoparticle-based cancer therapy and regulatory considerations, are provided aiming to accelerate the translation of these promising technologies from bench to bedside.

Amino Acid Adsorption Onto Magnetic Nanoparticles Reveals Correlations With Physicochemical Parameters

AbstractWe analyze the adsorption of the proteinogenic amino acids (AAs) glutamine, glutamic acid, lysine, tyrosine, proline, and valine onto bare iron oxide nanoparticles (approx. 10 nm). Aiming to identify the governing principles of low molecular weight coronae, which remain underinvestigated, our study covers broad concentration ranges up to the solubility limit of the AAs. Isothermal experiments reveal that the highly soluble AAs valine, proline, and lysine form extensive multilayers on the nanoparticle surface, and infrared measurements indicate intermolecular interactions, particularly with valine and lysine, for higher AA contents. Conversely, the low solubility of tyrosine and glutamic acid restricts their adsorption capacity, despite their higher partitioning on the solid surface. Parameters derived from fitting a classic saturation model seem to align with well‐documented physicochemical properties such as the hydrophobicity and the complexity indices – a promising first step towards formulating design principles. Scaling these parameters by the AA solubility reveals a clear correlation with the adsorption behavior. In adsorption experiments with AA model mixtures, sequential incubation increases the adsorption capacity for valine and proline, whereas simultaneous incubation with these AAs reduces tyrosine's capacity. Future studies should seek to elucidate adsorption patterns to advance our understanding of corona growth and evolution mechanisms.

Magnetic Effects in Textile Fibers Filled with Nanoconstituents Based on Iron Oxides

ABSTRACT The paper proves the possibility of providing magnetic properties in the process of saturation of textile fibers with a nanomixture of divalent and trivalent iron oxides. The mechanisms of interaction of nanostructures with natural and synthetic fibers are analyzed. The peculiarities of the introduction of magnetic components into flax, cotton, polyamide, and polyester fibers are determined. The relative number of particles with nanoscale in the total was statistically proved. To evaluate the macro effects of saturation, the relative amount of the accumulated mixture of divalent and trivalent iron oxides was determined, taking into account the previous fiber weight. Two basic constants characterizing the properties of textile fibers to magnetic interaction are proposed. It is proved that flax fibers exhibit the highest magnetic efficiency. The average size of iron oxide nanoparticles is 80–90 nanometers, which is confirmed by studies using electron microscopy. The final magnetization of the obtained textile materials provides an attractive magnetization of 20–30 mPascal. The magnetic field of magnetic textile fibers acts at a height of up to 6–7 mm. The directions of the use of fibers with magnetic properties are shown as a prospect for the development of textile smart products.

Exploring Multi-Parameter Effects on Iron Oxide Nanoparticle Synthesis by SAXS Analysis

Iron oxide nanoparticles (IONs) are extensively used in biomedical applications due to their unique magnetic properties. This study optimized ION synthesis via the co-precipitation method, exploring the impact of the reactant concentrations (Fe(II) and Fe(III)), NaOH concentration, temperature (30 °C–80 °C), stirring speed (0–1000 rpm), and dosing rate (10–600 s) on particle size and growth. Using small-angle X-ray scattering (SAXS), we observed, for example, that higher temperatures (e.g., 67 °C compared with 53 °C) led to a 50% increase in particle size, while the stirring speed and NaOH concentration also influenced nucleation and aggregation. These results provide comprehensive insights into optimizing synthetic conditions for targeted applications in biomedical fields, such as drug delivery and magnetic resonance imaging (MRI), where precise control over nanoparticle size and properties is crucial.

Augmenting Protein Degradation Capacity of PROTAC through Energy Metabolism Regulation and Targeted Drug Delivery.

The ubiquitin-proteasome system (UPS) is responsible for degrading over 70-80% of cellular proteins. Consequently, proteolysis-targeting chimeras (PROTACs) are developed to induce the ubiquitination and subsequent degradation of proteins of interest (POIs) by the UPS. To amplify the therapeutic efficacy of PROTACs, energy metabolism regulation is first harnessed to boost UPS function in tumor cells. Proteomic and ubiquitinome analyzes reveal that total ubiquitinated proteins and proteasome activity are significantly increased in 143B and MDA-MB-231 tumor cells following fasting-mimicking diet (FMD) treatment. As a result, the degradation efficiency of PROTACs targeting focal adhesion kinase (FAK-P) or bromodomain-containing protein 4 (BRD4-P) is significantly enhanced in FMD-treated 143B and MDA-MB-231 tumor cells. Then, silica-coated iron oxide nanoparticles are developed modified with tumor cell membranes for targeted delivery of PROTACs. Magnetic resonance imaging (MRI) and fluorescence imaging confirm that nanocarriers significantly improve the delivery efficiency of PROTACs in FMD-treated 143B or MDA-MB-231 tumors. In vivo studies demonstrate that the antitumor efficacy of FAK-P and BRD4-P is greatly augmented when combined with targeted delivery and FMD treatment. Overall, this study presents a strategy to enhance the efficacy of PROTACs in cancer therapy.

Magnetic Nanoparticle-Mediated Extraction and Electrochemical Detection of E. coli O157:H7 Genomic DNA

We report a rapid magnetic nanoparticle-mediated protocol to extract and detect DNA of E. coli O157:H7. Bare iron oxide nanoparticles (Fe3O4 NPs) were used as solid phase support to extract high purity DNA from concentrated and spiked water samples. Electrochemical detection of the DNA is achieved by employing polyaniline-functionalized magnetic nanoparticles (PANI-MNPs) which serve as DNA pre-concentrator and transducer. The DNA-based nanobiosensor shows good selectivity and sensitivity (detection limit of 0.10 ng/µL DNA) and offers faster and comparable results relative to conventional methods. This DNA extraction and detection method is expected to be applicable in food, water, and environmental samples.

Effect of mitochondrial oxidative stress on Regulatory T Cell manufacturing for clinical application in transplantation: results from a pilot study

The manufacturing process of Regulatory T (Treg) cells for clinical application begins with the positive selection of CD25+ cells using superparamagnetic iron-oxide nanoparticle (SPION)-conjugated anti-CD25 antibodies (spCD25) and immunomagnetic cell separation technology. Our findings revealed that the interaction of spCD25 with its cell target induced the internalization of the complex spCD25-Interleukin-2 Receptor. Accumulation of intracellular spCD25 triggered oxidative stress, causing delayed Treg expansion and temporary reduction in suppressor activity. This activation delay hindered the efficient generation of clinically competent cells. During this early phase, Treg cells exhibited elevated mitochondrial superoxide and lipid peroxidation levels, with concomitant decrease on mitochondrial respiration rates. The results uncovered the increased mitochondrial unfolded protein response (mitoUPR). This protective, redox-sensitive activity is inherent of Tregs when contrasted with homologous, spCD25-treated, conventional T cells. While the temporary effects of spCD25 on clinically competent cells did not impede their use in a safety/feasibility pilot study with kidney transplant recipients*, it is reasonable to anticipate a potential reduction in their therapeutic efficacy. The mechanistic understanding of the adverse effects triggered by spCD25 is crucial for improving the manufacturing process of clinically competent Treg cells, a pivotal step in the successful implementation of immune cell therapy in transplantation.*Clinical trial registration number NCT03284242 at ClinicalTrials.gov.

Silica-coated superparamagnetic iron oxide nanoparticles interacting with superoxide dismutase in the mouse primary hepatocytes

Given the great potential of superparamagnetic iron oxide nanoparticles (SPIONs) in the application of biomedical and water treatment fields, it is of vital significance to evaluate their toxicity and explore the underlying mechanism. Silica-coated SPIONs (SPIONs@SiO2) might generate oxidative stress and cytotoxicity by interfering antioxidant enzyme. This study investigated the response of superoxide dismutase (SOD) under SPIONs@SiO2-induced oxidative stress using a strategy integrating cellular and molecular methods. Results showed that intracellular SOD activity exhibited hormetic effects in response to SPIONs@SiO2-induced structural changes of SOD molecule and oxidative stress, which subsequently generated lipid oxidation and cell viability loss in the mouse primary hepatocytes. The structural changes and increasing activity of SOD molecule were resulted from the direct interaction with SPIONs@SiO2. Then, multi-spectroscopy, zeta potential measurements and isothermal titration calorimetry were used to study the interaction of SPIONs@SiO2 with SOD and the underlying mechanism. SOD interacts with SPIONs@SiO2 through electrostatic and hydrophobic forces, enhancing the hydrophobicity around Tyr 108. The enthalpy and entropy change of the interaction are 1.03 × 105 J.mol−1 and 474.6 J.mol−1.K−1, respectively, indicating the dominant driving forces are hydrophobic forces. The interaction led to the loosen of peptide chains and the reduction of aggregation state. And the α-helix content of SOD decreased to 13 % in the presence of SPIONs@SiO2.

Efficient synthesis of novel phenanthroline-dimedone derivatives using Pd@HQBI-SPION as a versatile palladium-immobilized catalyst

This paper presents the synthesis and application of a novel catalyst for carbon–carbon bond formations, comprising palladium immobilized on 2-(5-hydroxyquinolin-8-yl)-1H-benzo[d]imidazole-5-carboxylic acid modified superparamagnetic iron oxide nanoparticles (Pd@HQBI-SPION). The synthesis involved the attachment of HQBI ligands to SPION using APTES, followed by the immobilization of palladium. Characterization techniques, including FTIR, TEM, and magnetic measurements, confirmed the successful synthesis and structural integrity of Pd@HQBI-SPION. The catalytic activity of Pd@HQBI-SPION was evaluated in various carbon–carbon bond formation reactions, demonstrating high efficiency and reusability. 8 different derivatives bearing several electron withdrawing and electron donating functionalities were used as starting materials and the products were obtained in high isolated yields (75–97%). The catalyst exhibited excellent performance in one-pot synthesis of phenanthroline-dimedone polycyclic derivatives via C-alkylation followed by intramolecular O-alkylation of phenanthroline with dimedone. The products are obtained in high to excellent yields is described. This protocol presents a highly selective synthetic method for the construction of polycyclic aromatic compounds containing nitrogen and oxygen atoms.

Iron oxide nanoparticles synthesized by coprecipitation method: Impacts of zinc doping and surface functionalization by polyvinylpyrrolidone on the magnetic properties and heating efficiency

Iron oxide nanoparticles synthesized by coprecipitation method: Impacts of zinc doping and surface functionalization by polyvinylpyrrolidone on the magnetic properties and heating efficiency

Influence of annealing temperature on Fe₂O₃ nanoparticles: Synthesis optimization and structural, optical, morphological, and magnetic properties characterization for advanced technological applications

In this study, Iron oxide nanoparticles (Fe₂O₃ NPs) were synthesized using iron chloride hexahydrate (FeCl3·6H2O) and ammonia solution through a straightforward co-precipitation method. The nanoparticles were annealed at temperatures of 100 °C, 300 °C, 500 °C, 700 °C, and 900 °C, with one sample left unannealed. Comprehensive analyses were performed using X-Ray Diffraction (XRD), Fourier Transform Infrared Spectroscopy (FTIR), Zeta potential, Dynamic Light Scattering (DLS), Scanning Electron Microscopy (SEM), and UV–Vis Spectrophotometry. The XRD patterns confirmed the presence of both Maghemite (γ-Fe2O3) and Hematite (α-Fe2O3) phases, with a phase transition observed between 100 °C and 300 °C, and the most pronounced transition occurring at 500 °C. At this optimal temperature, the crystallite size was 19.14 nm, the average particle size was 37.36 nm, and the band gap energy was measured at 1.76 eV. SEM images revealed that nanoparticles formed clusters as the annealing temperature increased. The zeta potential measurements showed a range from 6.12 mV at 100 °C to −1.9 mV at 900 °C, indicating changes in particle stability. DLS analysis indicated a size increase from 86.81 nm at 300 °C to 1577 nm at 900 °C, reflecting aggregation trends. The reduction in band gap energy with higher temperatures is attributed to enhanced crystallinity and increased particle size. The magnetic properties of Fe₂O₃ NPs were evaluated using a Physical Property Measurement System (PPMS), revealing an increase in magnetic response with rising annealing temperatures. The transition from superparamagnetic γ-Fe₂O₃ to weakly ferromagnetic α-Fe₂O₃ was confirmed through changes in the hysteresis loop area and shape. These findings suggest that 500 °C is the optimal annealing temperature for producing Fe₂O₃ NPs with desirable properties for applications in targeted drug delivery, MRI contrast enhancement, and environmental remediation. This research advances the engineering of Fe₂O₃ NPs, paving the way for their use in various technological applications.

Construction of iron oxide nanoparticles modified with Angelica sinensis polysaccharide for the treatment of iron deficiency anemia

Construction of iron oxide nanoparticles modified with Angelica sinensis polysaccharide for the treatment of iron deficiency anemia

Correlative Multi-Scale Characterization of Nanoparticles Using Transmission Electron Microscopy

Chemical and physical properties of nanoparticles (NPs) are strongly influenced not only by the crystal structure of the respective material, including crystal structure defects but also by the NP size and shape. Contemporary transmission electron microscopy (TEM) can describe all these NP characteristics, however typically with a different statistical relevance. While the size and shape of NPs are frequently determined on a large ensemble of NPs and thus with good statistics, the characteristics on the atomic scale are usually quantified for a small number of individual NPs and thus with low statistical relevance. In this contribution, we present a TEM-based characterization technique, which can determine relevant characteristics of NPs in a scale-bridging way—from the crystal structure and crystal structure defects up to the NP size and morphology—with sufficient statistical relevance. This technique is based on a correlative multi-scale TEM approach that combines information on atomic scale obtained from the high-resolution imaging with the results of the low-resolution imaging assisted by a semi-automatic segmentation routine. The capability of the technique is illustrated in several examples, including Au NPs with different shapes, Au nanorods with different facet configurations, and multi-core iron oxide nanoparticles with a hierarchical structure.

A Multifunctional Exosome with Dual Homeostasis Disruption Augments cGAS-STING-Mediated Tumor Immunotherapy by Boosting Ferroptosis.

Ferroptosis has shown great potential in activating antitumor immunity. However, the cunning tumor cells can evade ferroptosis by increasing the efflux of iron and promoting the production of the reductant glutathione to mitigate oxidative stress. Herein, a multifunctional exosome loaded with manganese-doped iron oxide nanoparticles (MnIO), GW4869, and l-buthionine sulfoximine (BSO) is developed to disrupt the iron metabolism homeostasis and redox homeostasis to enhance tumor immunotherapy. The efficient transport of MnIO by exosomes and the inhibition of iron exocytosis by GW4869 led to a high retention of up to 29.57% ID/g for iron in the tumors. Such a high retention of iron, in combination with the BSO-induced disruption of the redox homeostasis, effectively promotes the ferroptosis of tumor cells. Consequently, the multifunctional exosomes that noticeably enhance ferroptosis by dual homeostasis disruption provoke the cGAS-STING-based antitumor immune response and effectively suppress tumor growth and lung metastasis in orthotopic breast cancer.

Magnetic targeting enhances the neuroprotective function of human mesenchymal stem cell-derived iron oxide exosomes by delivering miR-1228-5p

BackgroundTreating mitochondrial dysfunction is a promising approach for the treatment of post-stroke cognitive impairment (PSCI). HuMSC-derived exosomes (H-Ex) have shown powerful therapeutic effects in improving mitochondrial function, but the specific effects are unclear and its brain tissue targeting needs to be further optimized.ResultsIn this study, we found that H-Ex can improve mitochondrial dysfunction of neurons and significantly enhance the cognitive behavior performance of MCAO mice in OGD/R-induced SHSY5Y cells and MCAO mouse models. Based on this, we have developed an exosome delivery system loaded with superparamagnetic iron oxide nanoparticles (Spion-Ex) that can effectively penetrate the blood-brain barrier (BBB). The research results showed that under magnetic attraction, Spion-Ex can more effectively target the brain tissue and significantly improve mitochondrial function of neurons after stroke. Meanwhile, we further confirmed that miR-1228-5p is a key factor for H-Ex to improve mitochondrial function and cognitive behavior both in vivo and in vitro. The specific mechanism is that the increase of miR-1228-5p mediated by H-Ex can inhibit the expression of TRAF6 and activate the TRAF6-NADPH oxidase 1 (NOX1) pathway, thereby exerting protective effects against oxidative damage. More importantly, we found that under magnetic attraction, Spion-Ex exhibited excellent cognitive improvement effects by delivering miR-1228-5p.ConclusionsOur research found that H-Ex has a good therapeutic effect on PSCI by increasing the expression of miR-1228-5p in PSCI, while H-Ex loaded with Spion-Ex exhibited more excellent effects on improving mitochondrial function and cognitive impairment under magnetic attraction, which can be used as a novel strategy for the treatment of PSCI.

The synergistic effects on the magnetic CoNi and Fe3O4 nanoparticles co-embedded porous carbon toward enhanced microwave absorbing performance

Abstract Lightweight and environmentally friendly three-dimensional biomass-derived porous carbon (3D BPC) holds great potential as a highly effective material for microwave absorption (MA) applications. However, the high complex permittivity and lack of magnetic loss in a single 3D BPC lead to impedance mismatching and a limited absorption bandwidth. Developing 3D BPC–based absorbers with multiple loss mechanisms and excellent impedance matching remains a notable yet challenging task. In this study, inspired by a synergistic composition and microstructure design, 3D BPC co-embedded with magnetic cobalt–nickel (CoNi) and iron(III) oxide (Fe3O4) nanoparticles (3D BPC@CoNi@Fe3O4) was developed. 3D BPC@CoNi@Fe3O4 exhibited consistently low complex permittivity, primarily due to the suppression of conductive loss, whereas the introduction of magnetic phases (CoNi and Fe3O4) enhanced the magnetic loss. Optimised impedance matching, achieved through the synergistic regulation of the electromagnetic parameters, emerged as the key mechanism for improving the MA properties. The as-synthesised 3D BPC@CoNi@Fe3O4 composite, with only 20 wt.% loading demonstrated a wide effective absorption bandwidth (reflection loss [RL] < −10 dB) of 6.08 GHz and an impressive minimum RL value of −40.08 dB. These findings offer valuable insights into the development of high-performance 3D BPC–based microwave absorbers through composition and microstructure optimisation.