Search

Magnetic molecularly imprinted polymers (MMIPs) are used as artificial antibody materials. MMIPs have attracted a great deal of interest because of their low cost, wide practicality, predetermination, stability and their ability to achieve rapid separation from complex sample environments by the action of external magnetic field. MMIPs can simulate the natural recognition of entities. They are widely used because of their great advantages in terms of high selectivity. In this review article, the preparation methods of Fe3O4 NPs and a detailed summary of the commonly used methods for amination modification of Fe3O4 NPs are introduced, preparation of Ag NPs of different sizes and Au NPs of various shapes and preparation methods of magnetic molecularly imprinted plasmonic SERS composite nanoparticles such as Fe3O4@Ag NPs, Fe3O4/Ag NPs, Fe3O4@Au NPs, Fe3O4/Au NPs, Fe3O4@Au/Ag NPs and Fe3O4@Ag@Au NPs are main summarized. In addition, preparation process and the current application of MMIPs prepared from magnetic molecularly imprinted plasmonic SERS composite nanoparticles incorporating different functional monomers in a nuclear-satellite structure are also presented. Finally, the existing challenges and future prospects of MMIPs in applications are discussed. [ABSTRACT FROM AUTHOR]

Recently, metal and metal oxide nanoparticles have garnered significant scientific interest due to their distinctive properties and promising applications across diverse fields. This study details the successful synthesis and characterization of Fe3O4, Ag, and magnetite/silver core-shell (Fe3O4/Ag) nanocomposites, prepared through chemical reduction and co-precipitation methods. The successful incorporation of Ag into Fe3O4 nanoparticles was confirmed through X-ray diffraction (XRD), scanning electron microscopy (SEM), and Fourier transform infrared (FTIR) spectroscopy. Physical characterization revealed that the synthesized nanoparticles were small in size and highly pure. Their optical and electrical properties, including bandgap and electrical conductivity, were also characterized. The antibacterial activity of the synthesized Fe3O4, Ag, and Fe3O4/Ag nanoparticles was evaluated using Minimum Bactericidal Concentration (MBC) against pathogenic bacterial strains: S. typhimurium, P. aeruginosa, and S. aureus. The results demonstrated that Ag, Fe3O4, and Fe3O4/Ag nanoparticles could inhibit high concentrations of bacteria, indicating an excellent antimicrobial effect. Furthermore, the Fe3O4/Ag nanoparticles were found to be more effective than both Fe3O4 and Ag nanoparticles in inhibiting the selected pathogenic bacteria strains: S. typhimurium, P. aeruginosa, and S. aureus. [ABSTRACT FROM AUTHOR]

Industrial wastewater containing heavy metals, toxic compounds, and dyes poses significant environmental concerns. These substances harm aquatic and terrestrial life, making their removal essential for safeguarding biodiversity, ecosystems, and human health. This study focused on synthesizing Fe3O4 nanoparticles (NPs) and their chitosan-coated composite (CS/Fe3O4 NC) for effective wastewater treatment. The NPs were synthesized using the aqueous leaf extract of Laurus nobilis and then coated with chitosan extracted from shrimp. Characterization analysis confirmed the spherical morphology of both Fe3O4 NPs and CS/Fe3O4 NC, with average sizes of 21.3 nm and 28 nm, respectively. The Fe3O4 NPs and CS/Fe3O4 NC exhibited optical bandgap energies of 2.62 eV and 1.81 eV, respectively, indicating their potential as efficient photocatalysts. Photocatalytic efficiency was evaluated using methylene blue (MB) and ortho-toluidine blue (O-TB) dyes. After 75 min, CS/Fe3O4 NC achieved degradation rates of 99% for MB and 98.4% for O-TB, surpassing the rates of 79% and 60.0% achieved by Fe3O4 NPs alone. This highlights the superior performance of CS/Fe3O4 NC in dye degradation. Moreover, Fe3O4 NPs and CS/Fe3O4 NC were effective in removing heavy metals from petroleum water, achieving a remarkable 100% removal efficiency within 30 min. The removal of oil in water was 86% for Fe3O4 NPs and 90% for CS/Fe3O4 NC, while the reduction in total suspended solids was 71% and 78%, respectively. Overall, the synthesized Fe3O4 NPs and CS/Fe3O4 NC demonstrate promising potential for wastewater treatment by efficiently degrading dyes and removing heavy metals, oil, and suspended solids. [ABSTRACT FROM AUTHOR]

ABSTRACT Background Methods Results Conclusion Existing studies have shown that transferrin receptor (TfR) is highly expressed on the surface of lung cancer cells, and nanoparticles (NPs) have been widely used as delivery vehicles. The aim of this study was to investigate the effect of the targeted delivery of Fe3O4 NPs modified with transferrin (Tf) compared with photothermal treatment for lung cancer.The morphology and properties of Fe3O4 NPs modified with Tf were tested by internal morphological characterization experiments including transmission electron microscopy, particle size meter infrared spectrometer and other experiments. The delivery of materials was investigated by cell proliferation and apoptosis experiments, and western blot experiment was used to detect yes‐associated protein 1(YAP1) protein expression changes after delivering miR‐15a‐5p. In addition, animal models were constructed to further explore the targeting properties of the material.The results demonstrated that the nanomaterial has good stability and targeting properties. Meanwhile, we also discovered that the miR‐15a‐5p carried by NPs can inhibit cell growth after its entry to the lung cancer cells. The effect became more evident when the nanomaterials were assisted with laser therapy, as verified by in vivo and in vitro experiments. In terms of the related mechanism, miR‐15a‐5p inhibited YAP1 expression, which affected cell proliferation and apoptosis.In this study, Fe3O4 NPs modified with Tf delivered miR‐15a‐5p in combination with photothermal therapy for lung cancer. In future research, the targeted delivery of Tf and the photothermal synergy of nanomaterials will provide a theoretical basis for cancer treatment. [ABSTRACT FROM AUTHOR]

[Display omitted] Hypothesis: We hypothesize that simultaneous incorporation of ion channel peptides (in this case, potassium channel as a model) and hydrophobic magnetite Fe 3 O 4 nanoparticles (hFe 3 O 4 NPs) within lipidic hexagonal mesophases, and aligning them using an external magnetic field can significantly enhance ion transport through lipid membranes. Experiments: In this study, we successfully characterized the incorporation of gramicidin membrane ion channels and hFe 3 O 4 NPs in the lipidic hexagonal structure using SAXS and cryo-TEM methods. Additionally, we thoroughly investigated the conductive characteristics of freestanding films of lipidic hexagonal mesophases, both with and without gramicidin potassium channels, utilizing a range of electrochemical techniques, including impedance spectroscopy, normal pulse voltammetry, and chronoamperometry. Findings: Our research reveals a state-of-the-art breakthrough in enhancing ion transport in lyotropic liquid crystals as matrices for integral proteins and peptides. We demonstrate the remarkable efficacy of membranes composed of hexagonal lipid mesophases embedded with K+ transporting peptides. This enhancement is achieved through doping with hFe 3 O 4 NPs and exposure to a magnetic field. We investigate the intricate interplay between the conductive properties of the lipidic hexagonal structure, hFe 3 O 4 NPs, gramicidin incorporation, and the influence of Ca2+ on K+ channels. Furthermore, our study unveils a new direction in ion channel studies and biomimetic membrane investigations, presenting a versatile model for biomimetic membranes with unprecedented ion transport capabilities under an appropriately oriented magnetic field. These findings hold promise for advancing membrane technology and various biotechnological and biomedical applications of membrane proteins. [ABSTRACT FROM AUTHOR]

AbstractThe small size, surface effect, and tunneling effect of nanomaterials enable their applications in various fields, including catalysis, sensing. Fe3O4 has been widely used in nanotechnology owing to its excellent photoelectromagnetic properties. In this study, polygonal Fe3O4 nanoparticles were prepared through a high-temperature synthesis method. Subsequently, silica coating was applied via the Stöber method to obtain a nanomaterial with uniform particles. The prepared Fe3O4 exhibited a distinct crystal structure and an ultra-high saturation magnetization, reaching up to 134.2 emu/g. Moreover, the dodecyl trimethyl ammonium bromide (DTAB) templating agent facilitated the coating of Fe3O4 with silica. The coated Fe3O4@SiO2 particles featured a well-defined core–shell structure and corrosion resistance, making them highly promising candidates for magnetic targeting medical tools, magnetic resonance imaging agents and other biological applications. [ABSTRACT FROM AUTHOR]

4D printing magneto‐responsive shape memory polymers (SMPs) using biodegradable nanocomposites can overcome their low toughness and thermal resistance, and produce smart materials that can be controlled remotely without contact. This study presented the development of 3D/4D printable nanocomposites based on poly (lactic acid) (PLA)‐poly (butylene adipate‐co‐terephthalate) (PBAT) blends and magnetite (Fe3O4) nanoparticles. The nanocomposites are prepared by melt mixing PLA‐PBAT blends with different Fe3O4 contents (10, 15, and 20 wt%) and extruded into granules for material extrusion 3D printing. The morphology, dynamic mechanical thermal analysis (DMTA), mechanical properties, and shape memory behavior of the nanocomposites are investigated. The results indicated that the Fe3O4 nanoparticles are preferentially distributed in the PBAT phases, enhancing the storage modulus, thermal stability, strength, elongation, toughness, shape fixity, and recovery of the nanocomposites. The optimal Fe3O4 loading is found to be 10 wt%, as higher loadings led to nanoparticle agglomeration and reduced performance. The nanocomposites also exhibited fast shape memory response under thermal and magnetic activation due to the presence of Fe3O4 nanoparticles. The 3D/4D printable nanocomposites demonstrated multifunctional multi‐trigger shape‐memory capabilities and potential applications in contactless and safe actuation. [ABSTRACT FROM AUTHOR]

The immunosuppressive tumor microenvironment (TME) significantly inhibits the effective anti-tumor immune response, greatly affecting the efficacy of immunotherapy. Most tumor-associated macrophages (TAMs) belong to the M2 phenotype, which contributes significantly to the immunosuppressive effects in non-small cell lung cancer (NSCLC) TME. The interaction between signal regulatory protein α (SIRPα) expressed on macrophages and CD47, a transmembrane protein overexpressed on cancer cells, activates the "eat-me-not" signaling pathway, inhibiting phagocytosis. In this study, a folic acid (FA)-modified ultrasound responsive gene/drugs delivery system, named FA@ PFP @ Fe3O4 @LNB-SIRPα siRNA (FA-PFNB-SIRPα siRNA), was developed using 1,2-dioleoacyl-3-trimethylammonium-propane (DOTAP), FA-1,2-distearoyl-sn-glycero-3-phosphoethanolamine-N- [amino (polyethylene glycol)2000] (DSPE-PEG2000-FA), cholesterol, and perfluoropentane (PFP), for the delivery of siRNA encoding SIRPα mRNA and immune adjuvant Fe3O4 nanoparticles. Under ultrasound conditions, the nanobubbles effectively transfected macrophages, inhibiting SIRPα mRNA and protein expression, promoting the phagocytosis of TAMs, and synergistically reversing M2 polarization. This system promotes the infiltration of T cells, enhances the proliferation and activation of cytotoxic T cells, and inhibits the infiltration of immunosuppressive cells in tumor tissues. Administration of FA-PFNB-SIRPα siRNA combined with ultrasound significantly inhibits NSCLC progression. The study highlights the potential of ultrasound nanotechnology-enabled delivery of SIRPα siRNA and Fe3O4 as an effective strategy for macrophage-based immunotherapy to reshape the immunosuppressive TME for cancer therapy. [ABSTRACT FROM AUTHOR]

We have carried out a systematic investigation on the impact of Fe3O4 nanoparticles (NPs) and Rhizobium inoculation on nodulation and growth of common bean plants (cv. Red Guama, Phaseolus vulgaris). Three distinct treatments were conducted on the common bean plants: (i) exposure to Fe3O4 NPs; (ii) Rhizobium inoculation; and (iii) a combined treatment involving Fe3O4 NPs + Rhizobium inoculation, with non-treated plants as controls. Temperature and magnetic field dependence of magnetization, M(T, H), measurements were performed on both the soil, and dried organs of the plants including roots, nodules, stems, and leaves. M(T, H) analyses indicated a systematic increase in magnetization across organs of plants treated with Fe3O4 NPs and combined Fe3O4 NPs + Rhizobium. We have found the magnetic contribution, generally related to Fe content in the soil and plant organs, significantly increased in plants exposed to Fe3O4 NPs, further indicating absorption, translocation, and accumulation of Fe3O4 NPs in the areal parts of the plants. Plants treated with Fe3O4 NPs and combined Fe3O4 NPs + Rhizobium exhibited Fe3O4 NPs accumulation in all organs with increasing concentrations of 69.7 to 74.1 NNPs/g in roots, 5.6 to 7.7 NNPs/g in stems, and 3.1 to 5.5 NNPs/g in leaves, respectively. The iron concentration in nodules was found to be close to 65 NNPs/g. No appreciable difference in the absorption index AI of roots between plants treated with Fe3O4 NPs (~ 1.73%) and Fe3O4 NPs + Rhizobium (~ 1.79%) has been observed. The translocation index TI increased by ~ 46% in plants treated with Fe3O4 NPs + Rhizobium (6.9%) compared to Fe3O4 NPs (4.3%). Treated plants showed improved symbiotic performance including nodule leghaemoglobin and iron content, number of active nodules per plant, and nodule dry weight. The best result was obtained using the combined treatment of Fe3O4 NPs + Rhizobium. This study provides evidence that M(T,H) measurements constitute a valuable tool in monitoring the uptake, translocation, and accumulation of Fe3O4 NPs in plant organs of common bean plants. [ABSTRACT FROM AUTHOR]

In this investigation, a novel Fe3O4-enhanced biochar derived from winter melon (Fe3O4@WBC) was synthesised by an innovative ethylene glycol reduction and thermal polymerisation approach for efficiently eliminating U(VI) from contaminated environments. The factors influencing uranium(VI) adsorption by Fe3O4@WBC, including pH, adsorbent dosage, time, temperature, and initial U(VI) concentration were explored. The material's performance was characterised, and the underlying mechanism of U(VI) removal was analysed using various techniques. The results demonstrated that Fe3O4@WBC effectively removed U(VI), achieving a maximum adsorption capacity of 199.84 mg g−1 at a pH of 5.0. These findings provided a theoretical basis for the treatment of wastewater contaminated with U(VI). [ABSTRACT FROM AUTHOR]

Here, the core-shell structured FeSiBCuNb/Fe 3 O 4 soft magnetic composites (SMCs) were successfully designed and fabricated by coating Fe 3 O 4 magnetic nanoparticles on the surface of phosphorylated FeSiBCuNb powder. The effects of Fe 3 O 4 and Polyvinylpyrrolidone (PVP) contents on the micromorphology, interface structure, and soft magnetic properties of SMCs were systematically investigated. The results demonstrate that the Fe 3 O 4 magnetic nanoparticles are uniformly distributed on the surface of magnetic powders, which fill up the air gap in-between the magnetic powder and increase the resistivity. It shows that the permeability gradually decreases with the increase of Fe 3 O 4 from 0 wt% to 1 wt%, while the loss decreases first and then increases. The loss separation of SMCs indicates that the Fe 3 O 4 nanoparticles effectively reduce the hysteresis loss and eddy current loss. Furthermore, the FeSiBCuNb/Fe 3 O 4 SMCs with the addition of PVP as a binder enhance the binding force between Fe 3 O 4 nanoparticles and the powder matrix, which facilitates the formation of a uniform and dense interface structure. When adding 0.3 wt% PVP + Fe 3 O 4 nanoparticles, the FeSiBCuNb/Fe 3 O 4 SMCs exhibit excellent soft magnetic properties with ultra-low loss of 138.5 kW/m3 (100 mT/50 kHz), high permeability of 54, and good frequency stability. The presented results provide a new strategy for synthesizing ultra-low core loss and frequency stability of core-shell structured SMCs, which has great potential for applications at high frequencies. [ABSTRACT FROM AUTHOR]

Abstract The immunosuppressive tumor microenvironment (TME) significantly inhibits the effective anti-tumor immune response, greatly affecting the efficacy of immunotherapy. Most tumor-associated macrophages (TAMs) belong to the M2 phenotype, which contributes significantly to the immunosuppressive effects in non-small cell lung cancer (NSCLC) TME. The interaction between signal regulatory protein α (SIRPα) expressed on macrophages and CD47, a transmembrane protein overexpressed on cancer cells, activates the "eat-me-not" signaling pathway, inhibiting phagocytosis. In this study, a folic acid (FA)-modified ultrasound responsive gene/drugs delivery system, named FA@ PFP @ Fe3O4 @LNB-SIRPα siRNA (FA-PFNB-SIRPα siRNA), was developed using 1,2-dioleoacyl-3-trimethylammonium-propane (DOTAP), FA-1,2-distearoyl-sn-glycero-3-phosphoethanolamine-N- [amino (polyethylene glycol)2000] (DSPE-PEG2000-FA), cholesterol, and perfluoropentane (PFP), for the delivery of siRNA encoding SIRPα mRNA and immune adjuvant Fe3O4 nanoparticles. Under ultrasound conditions, the nanobubbles effectively transfected macrophages, inhibiting SIRPα mRNA and protein expression, promoting the phagocytosis of TAMs, and synergistically reversing M2 polarization. This system promotes the infiltration of T cells, enhances the proliferation and activation of cytotoxic T cells, and inhibits the infiltration of immunosuppressive cells in tumor tissues. Administration of FA-PFNB-SIRPα siRNA combined with ultrasound significantly inhibits NSCLC progression. The study highlights the potential of ultrasound nanotechnology-enabled delivery of SIRPα siRNA and Fe3O4 as an effective strategy for macrophage-based immunotherapy to reshape the immunosuppressive TME for cancer therapy. Graphical Abstract

Background and purpose: Antibiotics are crucial in various scientific fields, including human and veterinary medicine, and are widely utilized medicinal compounds. Ciprofloxacin is a widely used antibiotic in the treatment of infections, most of which is excreted unmetabolized and finally enters water sources through the discharge of sewage and effluents. Even at low concentrations, ciprofloxacin in sewage and effluents can cause ecological harm and pose significant risks to human health. It is crucial to devise effective solutions for the removal of this antibiotic. Advanced Oxidation Processes (AOPs) are a promising method for the future removal of antibiotics, particularly in aquatic solutions, due to their potential to effectively remove ciprofloxacin. This study investigated the antibacterial and catalytic activity of synthesized magnetite nanoparticles (MNPs) (Fe3O4) in removing ciprofloxacin. Materials and methods: In this experimental research, Fe3O4 magnetic nanoparticles (MNPs) were prepared using the co-precipitation method. The nanoparticles were then examined for their physical and structural characteristics using scanning electron microscopy(SEM), X-ray powder diffraction (XRD), transmission electron microscopy (TEM), and BET technique. Fe3O4 magnetic nanoparticles (MNPs) were initially synthesized, and their properties were determined. We performed separate investigations to assess the effectiveness of various methods for removing ciprofloxacin. This included evaluating ultrasound alone (US), hydrogen peroxide alone, magnetite nanoparticles alone (MNPs), and combinations such as ultrasound with hydrogen peroxide, hydrogen peroxide with magnetite nanoparticles, and magnetite nanoparticles with ultrasound. All tests were conducted under the same conditions. The first step assessed the catalytic activity of synthesized nanoparticles for ciprofloxacin through the Fenton process. In this study, experimental parameters such as Fe3O4 catalyst dosage, initial pH of the solution, Hydrogen peroxide concentration, reaction time, and initial antibiotic concentration were investigated. In the second step, the antibacterial efficacy of synthesized nanoparticles against Escherichia coli and Staphylococcus aureus was determined via the Broth Macro dilution method. Results: The examination of the characteristics of synthesized nanoparticles showed that the average size of magnetite nanoparticles is approximately 20-30 nm. TEM results confirmed that the synthesized nanoparticles have a uniform size and structure. The combined process of MNPs/hydrogen peroxide/US exhibited the highest removal efficiency at 88.36%. This high efficiency can be attributed to the direct effect of the reaction between Fenton agents and ultrasonic waves, leading to the generation of numerous hydroxyl radicals. The maximum removal of ciprofloxacin was achieved in 0.5 g/L catalyst, pH=3, five mM hydrogen peroxide concentration, 550 W ultrasonic power, and 60 min reaction time. For Escherichia coli and Staphylococcus aureus, the Minimum Inhibitory and Minimum bactericidal concentrations were 3.125, 6.25, and 1.56, 3.125 μg/mL, respectively. Conclusion: Synthesized iron magnetite nanoparticles have high antibacterial properties against bacterial strains and many catalytic properties in the Sono Fenton process to remove ciprofloxacin, so this process can be an effective method for eliminating hospital and pharmaceutical wastewater.

Cow dung is an abundant agricultural by‐product that poses disposal challenges. Converting this waste into a valuable energy resource aligns with sustainable waste management practices and contributes to a circular economy. This research aims at Cow dung disposal by carbonization and gasification for hydrogen generation and maximizes it by optimizing the process parameters. In the pyrolysis‐carbonization process, the influence of temperature on cow dung and its biochar characteristics was initially investigated. On the cow dung feedstock, different operating temperatures at about 400, 500, and 600 °C and response times of about 30, 60, and 120 min were tested. With CD450 as the feedstock, the gas concentrations and hydrogen yield were around 62 vol% and 0.69 m3 kg−1, respectively, for longer reaction times. Similar to this, the gas concentration and yield value for hydrogen at 600 °C gasification temperature is around 64 vol% and 0.91 m3 kg−1. Cow dung is evidently acceptable for larger hydrogen production at higher gasification temperatures and reaction times when the carbonization temperature is 450 °C. In addition, when compared to feedstock without adding nanoparticles, including Fe3O4 nanoparticles may increase the hydrogen concentration and yield by around 13.5 % and 4.21 %, respectively. [ABSTRACT FROM AUTHOR]

The demand for polymer composites with improved mechanical and electrical properties is crucial for advanced aerospace, electronics, and energy storage applications. Single-walled carbon nanotubes (SWCNTs) and iron oxide (Fe3O4) nanoparticles are key fillers that enhance these properties, yet challenges like orientation, uniform dispersion, and agglomeration must be addressed to realize their full potential. This study focuses on developing SWCNTs/Fe3O4 epoxy composites by keeping the SWCNT concentration constant at 0.03 Vol.% and varying with Fe3O4 concentrations at 0.1, 0.5, and 1 Vol.% for two different configurations: randomly orientated (R-) and magnetic field-assisted horizontally aligned (A-) SWCNTs/Fe3O4 epoxy composites, and investigates the effects of filler concentration, dispersion, and magnetic alignment on the mechanical and electrical properties. The research reveals that both composite configurations achieve an optimal mechanical performance at 0.5 Vol.% Fe3O4, while A- SWCNTs/Fe3O4 epoxy composites outperformed at all concentrations. However, at 1 Vol.% Fe3O4, mechanical properties decline due to nanoparticle agglomeration, which disrupts stress distribution. In contrast, electrical conductivity peaks at 1 Vol.% Fe3O4, indicating that the higher density of Fe3O4 nanoparticles enhances the conductive network despite the mechanical losses. This study highlights the need for precise control over filler content and alignment to optimize mechanical strength and electrical conductivity in SWCNTs/Fe3O4 epoxy nanocomposites. [ABSTRACT FROM AUTHOR]

Utilizing biomass waste as a potential resource for cellulose production holds promise in mitigating environmental consequences. The current study aims to utilize pineapple biowaste extract in producing bacterial cellulose acetate-based membranes with magnetic nanoparticles (Fe3O4 nanoparticles) through the fermentation and esterification process and explore its characteristics. The bacterial cellulose fibrillation used a high-pressure homogenization procedure, and membranes were developed incorporating 0.25, 0.50, 0.75, and 1.0 wt.% of Fe3O4 nanoparticles as magnetic nanoparticle for functionalization. The membrane characteristics were measured in terms of Scanning Electron Microscope, X-ray diffraction, Fourier Transform Infrared, Vibrating Sample Magnetometer, antibacterial activity, bacterial adhesion and dye adsorption studies. The results indicated that the surface morphology of membrane changes where the bacterial cellulose acetate surface looks rougher. The crystallinity index of membrane increased from 54.34% to 68.33%, and the functional groups analysis revealed that multiple peak shifts indicated alterations in membrane functional groups. Moreover, adding Fe3O4-NPs into membrane exhibits paramagnetic behavior, increases tensile strength to 73%, enhances activity against E. coli and S. aureus, and is successful in removing bacteria from wastewater of the river to 67.4% and increases adsorption for anionic dyes like Congo Red and Acid Orange. [ABSTRACT FROM AUTHOR]

The experimental study examined the potential impact of biosynthesized triiron tetraoxide nanoparticles (Fe3O4 NPs) on seed germination and germination indices of finger millet (Eleusine coracana) to advance sustainable and biocompatible nano-agriculture. The successful production of Fe3O4 NPs, which was capped with numerous phytochemicals found in the Colocasia esculenta extract, was determined by the results of several characterization processes like FTIR, UV, XRD, and FE-SEM. The presence of the peak in UV with 325 nm with band gap energy 2.60 eV indicates the synthesized NPs. The vibration mode of the Fe–O bond at 530.95 cm−1 and 459.30 cm−1 was analyzed in FTIR. Utilizing XRD, NPs with a mean crystalline size of 3.6 nm were discovered, and crucial EDS examination proved the iron element's presence. The FE-SEM images displayed a nanorod appearance with an average diameter of 43.7 nm whereas DLS shows 739 nm due to the aggregation of nanoparticles. It was observed that the nanoparticle has a significant antioxidant capability which was expressed using several assays. Additionally, this experiment was conducted to examine the impact of biogenic Fe3O4 NPs on the germination of Eleusine coracana seeds as well as to examine other aspects of plant growth, including root and shoot lengths, seed vigor index germination rates, peak value (PV), and mean daily germination. A total of four different Fe3O4 NP concentrations (25, 50, 75, and 100 μg/mL) were investigated. The Eleusine coracana seeds' ability to germinate and thrive is affected by the Fe3O4 NPs' penetration. Efficient treatment with Fe3O4 NPs resulted in a notable improvement in germination index values for Eleusine coracana seeds compared to untreated seeds. In addition to that, the nanoparticles were also treated with Allium cepa and its roots were examined for the mitotic cycle, and lipid peroxidation and Evans blue test were performed. [ABSTRACT FROM AUTHOR]

Background and purpose: Antibiotics are crucial in various scientific fields, including human and veterinary medicine, and are widely utilized medicinal compounds. Ciprofloxacin is a widely used antibiotic in the treatment of infections, most of which is excreted unmetabolized and finally enters water sources through the discharge of sewage and effluents. Even at low concentrations, ciprofloxacin in sewage and effluents can cause ecological harm and pose significant risks to human health. It is crucial to devise effective solutions for the removal of this antibiotic. Advanced Oxidation Processes (AOPs) are a promising method for the future removal of antibiotics, particularly in aquatic solutions, due to their potential to effectively remove ciprofloxacin. This study investigated the antibacterial and catalytic activity of synthesized magnetite nanoparticles (MNPs) (Fe3O4) in removing ciprofloxacin. Materials and methods: In this experimental research, Fe3O4 magnetic nanoparticles (MNPs) were prepared using the co-precipitation method. The nanoparticles were then examined for their physical and structural characteristics using scanning electron microscopy(SEM), X-ray powder diffraction (XRD), transmission electron microscopy (TEM), and BET technique. Fe3O4 magnetic nanoparticles (MNPs) were initially synthesized, and their properties were determined. We performed separate investigations to assess the effectiveness of various methods for removing ciprofloxacin. This included evaluating ultrasound alone (US), hydrogen peroxide alone, magnetite nanoparticles alone (MNPs), and combinations such as ultrasound with hydrogen peroxide, hydrogen peroxide with magnetite nanoparticles, and magnetite nanoparticles with ultrasound. All tests were conducted under the same conditions. The first step assessed the catalytic activity of synthesized nanoparticles for ciprofloxacin through the Fenton process. In this study, experimental parameters such as Fe3O4 catalyst dosage, initial pH of the solution, Hydrogen peroxide concentration, reaction time, and initial antibiotic concentration were investigated. In the second step, the antibacterial efficacy of synthesized nanoparticles against Escherichia coli and Staphylococcus aureus was determined via the Broth Macro dilution method. Results: The examination of the characteristics of synthesized nanoparticles showed that the average size of magnetite nanoparticles is approximately 20-30 nm. TEM results confirmed that the synthesized nanoparticles have a uniform size and structure. The combined process of MNPs/hydrogen peroxide/US exhibited the highest removal efficiency at 88.36%. This high efficiency can be attributed to the direct effect of the reaction between Fenton agents and ultrasonic waves, leading to the generation of numerous hydroxyl radicals. The maximum removal of ciprofloxacin was achieved in 0.5 g/L catalyst, pH=3, five mM hydrogen peroxide concentration, 550 W ultrasonic power, and 60 min reaction time. For Escherichia coli and Staphylococcus aureus, the Minimum Inhibitory and Minimum bactericidal concentrations were 3.125, 6.25, and 1.56, 3.125 μg/mL, respectively. Conclusion: Synthesized iron magnetite nanoparticles have high antibacterial properties against bacterial strains and many catalytic properties in the Sono Fenton process to remove ciprofloxacin, so this process can be an effective method for eliminating hospital and pharmaceutical wastewater. [ABSTRACT FROM AUTHOR]

As the global climate environment continues to change, the frequency of extreme temperature events is expected to increase. The temperature stress environments of low and high temperatures can directly or indirectly affect the growth of rice (Oryza sativa L.), affecting its normal metabolism, which in turn can have an impact on yields and threaten global food security. Agriculture needs new technologies to mitigate temperature stress and improve grain yield and quality. In this study, two iron (Fe)-based nanoparticles (NPs), Fe2O3 NPs and Fe3O4 NPs, as well as groups of Fe ions corresponding to the Fe concentration, were selected for hydroponic experiments on rice under normal (25°C), low (20°C), and high (38°C) temperature conditions, respectively. It was found that low and high temperature stresses reduced stem length (3 and 7.02%), root length (49.53 and 26.01%), and aboveground (52.49 and 26.04%) and belowground biomass (53.94 and 35.22%) in rice. Both Fe2O3 NPs and Fe3O4 NPs could promote root development by nutrient uptake, transferring to the aboveground to enhance photosynthesis, and promoting the activity of antioxidant enzymes to eliminate oxidative stress to alleviate the stress of low and high temperatures. The Fe3O4 NPs were more stable and had obvious effects at both high and low temperatures. [ABSTRACT FROM AUTHOR]

The rampant hepatitis B virus (HBV) seriously endangers human health, and hepatitis B surface antigen (HBsAg) is its early diagnostic marker. Therefore, it is crucial to construct a fast and highly sensitive HBsAg detection method. Based on high-efficiency magnetic separation technology and fluorescent composite material labelling technology, an accurate, fast and sensitive fluorescent immunosensing system for HBsAg detection was developed. Immunomagnetic beads constructed from carboxyl-functionalized Fe3O4 nanoparticles (Fe3O4-COOH) with excellent magnetic response performance were used as efficient capture carriers for HBsAg. Immunofluorescence composite microspheres constructed based on ultra-stable polystyrene-coated CsPbBr3 perovskite nanocrystals (CPB@PSAA) with high hydrophilic properties, were excellent fluorescent markers for HBsAg. Using this sensitive sandwich fluorescence sensing system a good linear relationship within the range of 0.2–15 ng/mL was established between HBsAg concentration and fluorescence intensity with a limit of detection (LOD) of 0.05 ng/mL. The system obtained satisfactory results when tested on real human serum samples. The magnetic-assisted fluorescence immune-sandwich sensor system has broad application prospects in biomedicine such as rapid and early diagnosis and effective prevention of infectious diseases. [ABSTRACT FROM AUTHOR]

Textile industry effluents contain several hazardous substances, such as dye-containing effluents, which pose environmental and aesthetic challenges. Presently, the microbial-based remediation process is in use. This study investigated the application of ferrous–ferric oxide (Fe3O4) nanoparticles, a readily formulated nanoadsorbent, to remove scattered dye molecules from industrial effluents. The ferrous–ferric oxide nanoparticles were prepared using a chemical co-precipitation method. The nanoparticles had 26.93 emu g−1 magnetization, with sizes smaller than 20 nm, and possessed a highly purified cubic spinel crystallite structure. The catalytic activity of the iron oxide depended on the dose, photocatalytic enhancer, i.e., H2O2 level, pH of the reaction medium, and dye concentration. We optimized the Fenton-like reaction to work best using 1.0 g/L of ferrous–ferric oxide nanoparticles, 60 mM oxalic acid at pH 7.0, and 60 ppm of dye. Iron oxides act as photocatalysts, and oxalic acid generates electron–hole pairs. Consequently, higher amounts of super-radicals cause the rapid degradation of dye and pseudo-first-order reactions. Liquid chromatography–mass spectrometry (LC-MS) analysis revealed the ferrous–ferric oxide nanoparticles decolorized and destroyed Disperse Red 277 in 180 min under visible light. Hence, complete demineralization is observed using a photo-Fenton-like reaction within 3 h under visible light. These high-capacity, easy-to-separate next-generation adsorption systems are suggested to be suitable for industrial-scale use. Ferrous–ferric oxide nanoparticles with increased adsorption and magnetic properties could be utilized to clean environmental pollution. [ABSTRACT FROM AUTHOR]

In this study, nanosilica was utilized as a substrate for the deposition of polymeric layers imprinted with copper-(II) ions, which were used for the colorimetric detection of Cu-(II). The nanosilica was first prepared using the Stober method and then used in an in situ polymerization of aminopropyltriethoxysilane and tetraethyl orthosilicate in the presence of the template copper ions. Following the elution process, the polymer was washed with a proper solution to obtain the Cu-(II)-imprinted polymers on nanosilica (SiO2@MIP), which were characterized by transmission electron microscopy to reveal the diameter of the silica core to be approximately 350 nm, and the polymeric layers were about 40 nm in thickness. The SiO2@MIP was successfully employed in the colorimetric detection of Cu-(II) in aqueous solutions with concentrations ranging from 0.001 to 0.1 M, using xylenol orange as the colorimetric indicator. The color change could be easily observed by the naked eye, with colors shifting from yellowish-orange to dark purple. The sensing signal was quantitatively assessed using UV–vis absorbance, and the limit of detection for Cu-(II) was determined to be 0.064 mg/mL. Additionally, SiO2@MIP was demonstrated to be highly specific for the adsorption of Cu-(II) with the imprinted cavities. The proposed Cu-(II) imprinted polymers show promise in real-world detection of Cu-(II) with advantages of low cost, user-friendliness, and high selectivity. [ABSTRACT FROM AUTHOR]

In this study, an amperometric dopamine sensor based on carbon nanofibers (CNF), Fe3O4 nanoparticles (Fe3O4NP), and silver nanoparticles (AgNP) modified glassy carbon electrode (GCE) was developed. In order to determine the optimum surface composition, the effects of CNF amount, Fe3O4 amount and the electrodeposition step of AgNP were investigated. Optimum experimental parameters such as working potential and pH of test solution were also explored. The morphological and electrochemical properties of the AgNP/CNF − Fe3O4NP/GCE were studied using scanning electron microscopy, cyclic voltammetry, and chronoamperometry. The AgNP/CNF − Fe3O4NP/GCE showed linear response to dopamine between 2.0 × 10−7 and 5.5 × 10−4 M with a detection limit of 1.8 × 10−7 M and sensitivity of 37.24 μA mM−1. Analytical performance characteristics such as reproducibility, reusability, and selectivity were also investigated for the presented dopamine sensor. The sensor was successfully applied to the detection of dopamine in dopamine hydrochloride injection samples using the standard addition method and good recoveries were obtained. [ABSTRACT FROM AUTHOR]

This study employs molecular dynamic simulations to investigate the sintering mechanisms of Fe3O4 nanoparticles and determine the sintering activation energy. The melting temperature has been calculated using atomic volume to verify the accuracy of this EAM function and its parameters. Neck width has been defined to demonstrate the sintering degree under different temperatures, from 1373 K to 1773 K. Following sections divide the whole evolution into three mechanisms: surface diffusion, grain boundary diffusion and viscous flow according to the atomic migration vector. Finally, the sintering activation energy has been figured out based on the neck diameter ratio which later has been employed to predict the neck growth curve at 1523 K. Therefore, this investigation reveals the sintering mechanisms and introduces a method to predict the growth rate using activation energy. [ABSTRACT FROM AUTHOR]

Featured Application: This magnetic marker material is used for large-scale field signal marking, offering the advantages of stable, rapid, and portable detection. With the widespread application of tagging materials, existing chemical tagging materials exhibit limitations in stability and detection under field conditions. This study introduces a novel magnetic detection scheme. Hydrophilic material-modified Fe3O4 nanoparticles (COOH-PEG@Fe3O4 NPs) were synthesized using the co-precipitation technique. The content of Fe3O4 nanoparticles in the magnetic tagging liquid can reach up to 10 wt% and remain stable in an aqueous phase system for seven days. This research details the preparation process, the characterization methods (IR, 1HNMR, EDX, XRD, SEM, TEM, VSM, DLS), and the performance effects of the materials in magnetic tagging. Experimental results indicate that COOH-PEG@Fe3O4 NPs exhibit high remanence intensity (Br = 1.75 emu/g) and considerable stability, making it possible to quickly detect tagged liquids in the field using portable flux meters and optical pump magnetometers. This study provides new insights into the design and application of magnetic tagging materials, making it particularly suitable for long-term tagging and convenient detection in field scenarios. [ABSTRACT FROM AUTHOR]

Salicylic acid (SA) has strong tendency to form complexes with iron (III). Depending upon the concentrations of SA, the complexes formed are FeR+, FeR2+, FeR32+where R represents salicylate ion (-OC₆H₄COO-). Fe3O4 nanoparticles binds with the salicylate ions through the sites having Fe3+ and at the site containing Fe2+ reacts with H2O2 to produces OH* radicals. The OH* radicals oxidise the salicylic acid attached to Fe3O4 nanoparticles. Thus, the degradation occurs through the formation of SA-Fe3O4 nanoparticles complexes and then followed by the reaction with H2O2 at the nanoparticle site. FT-IR, TGA were used to confirm the synthesis of Fe3O4 nanoparticles as well as to investigate SA-Fe3O4 nanoparticles complex formation and the degradation of the complex by H2O2. Spectrophotometric studies were employed for the monitoring of the degradation of SA at the surface. Here, the nanoparticles act as platform to which both the reactants SA and H2O2 get activated and the degradation reaction occurs. The concentrations of SA, H2O2, nanoparticle dosage, surfactants and polymers were changed and the % degradation were noted. It has been observed that the degradation percentage decreased with the increase in nanoparticle dosage, [surfactant] and [polymers]. The [H2O2] and [HClO4] gave peaked-like curve for the degradation of SA for the plot of % degradation versus concentrations of H2O2 and HClO4. Degradation of SA was observed maximum at [H2O2](= 8.0 × 10−4 mol dm−3) and at [HClO4] (= 1.0 × 10−2 mol dm−3).

Magnetite (Fe3O4) particles have been widely reported to enhance the anammox's activity in anammox granular sludge (AnGS), yet the underlying mechanisms remain unclear. This study demonstrates that both Fe3O4 microparticles (MPs) and nanoparticles (NPs) at a dosage of 200 mg Fe3O4/L significantly increased the specific anammox activity (SAA) of AnGS. Additionally, the transcriptional activities of the hzs and hdh genes involved in the anammox process, as well as the heme c content in AnGS, were also notably enhanced. Notably, Fe3O4 NPs were more effective than MPs in boosting anammox activity within AnGS. Mechanistically, Fe3O4 MPs released free iron, which anammox bacteria utilized to promote the synthesis of key enzymes, thereby enhancing their activity. Compared to MPs, Fe3O4 NPs not only elevated the synthesis of these key enzymes to a higher level but also induced a nanofluids effect on the surface of AnGS, improving substrate permeability and accessibility to intragranular anammox bacteria. Moreover, the nanofluids effect was identified as the primary mechanism through which Fe3O4 NPs enhanced anammox activity within AnGS. These findings provide new insights into the effects of nanoparticles on granular sludge systems, extending beyond AnGS.

Abstract Background The general sluggish clearance kinetics of functional inorganic nanoparticles tend to raise potential biosafety concerns for in vivo applications. Renal clearance is a possible elimination pathway for functional inorganic nanoparticles delivered through intravenous injection, but largely depending on the surface physical chemical properties of a given particle apart from its size and shape. Results In this study, three small-molecule ligands that bear a diphosphonate (DP) group, but different terminal groups on the other side, i.e., anionic, cationic, and zwitterionic groups, were synthesized and used to modify ultrasmall Fe3O4 nanoparticles for evaluating the surface structure-dependent renal clearance behaviors. Systematic studies suggested that the variation of the surface ligands did not significantly increase the hydrodynamic diameter of ultrasmall Fe3O4 nanoparticles, nor influence their magnetic resonance imaging (MRI) contrast enhancement effects. Among the three particle samples, Fe3O4 nanoparticle coated with zwitterionic ligands, i.e., Fe3O4@DMSA, exhibited optimal renal clearance efficiency and reduced reticuloendothelial uptake. Therefore, this sample was further labeled with 99mTc through the DP moieties to achieve a renal-clearable MRI/single-photon emission computed tomography (SPECT) dual-modality imaging nanoprobe. The resulting nanoprobe showed satisfactory imaging capacities in a 4T1 xenograft tumor mouse model. Furthermore, the biocompatibility of Fe3O4@DMSA was evaluated both in vitro and in vivo through safety assessment experiments. Conclusions We believe that the current investigations offer a simple and effective strategy for constructing renal-clearable nanoparticles for precise disease diagnosis. Graphical Abstract

Ultra-small magnetic Fe3O4 nanoparticles are successfully synthesized in basic solutions by using the radiolytic method of the partial reduction in FeIII in the presence of poly-acrylate (PA), or by using the coprecipitation method of FeIII and FeII salts in the presence of PA. The optical, structural, and magnetic properties of the nanoparticles were examined using UV–Vis absorption spectroscopy, high-resolution transmission electron microscopy (HRTEM), X-ray diffraction (XRD), and SQUID magnetization measurements. The HRTEM and XRD analysis confirmed the formation of ultra-small magnetite nanoparticles in a spinel structure, with a smaller size for radiation-induced particles coated by PA (5.2 nm) than for coprecipitated PA-coated nanoparticles (11 nm). From magnetization measurements, it is shown that the nanoparticles are superparamagnetic at room temperature. The magnetization saturation value Ms = 50.1 A m2 kg−1 of radiation-induced nanoparticles at 60 kGy is higher than Ms = 18.2 A m2 kg−1 for coprecipitated nanoparticles. Both values are compared with nanoparticles coated with other stabilizers in the literature. [ABSTRACT FROM AUTHOR]

In this study, Fe3O4 nanoparticles (FeNPs) decorated with halogenated perylene diimides (PDIs) have been used for capturing VOCs (volatile organic compounds) through noncovalent binding. Concretely, we have used tetrachlorinated/brominated PDIs as well as a nonhalogenated PDI as a reference system. On the other hand, methanol, ethanol, propanol, and butanol were used as VOCs. Experimental studies along with theoretical calculations (the BP86-D3/def2-TZVPP level of theory) pointed to two possible and likely competitive binding modes (lone pair–π through the π-acidic surface of the PDI and a halogen bond via the σ-holes at the Cl/Br atoms). More in detail, thermal desorption (TD) experiments showed an increase in the VOC retention capacity upon increasing the length of the alkyl chain, suggesting a preference for the interaction with the PDI aromatic surface. In addition, the tetrachlorinated derivative showed larger VOC retention times compared to the tetrabrominated analog. These results were complemented by several state-of-the-art computational tools, such as the electrostatic surface potential analysis, the Quantum Theory of Atoms in Molecules (QTAIM), as well as the noncovalent interaction plot (NCIplot) visual index, which were helpful to rationalize the role of each interaction in the VOC···PDI recognition phenomena. [ABSTRACT FROM AUTHOR]

Biodiesel is a mixture of fatty acid alkyl esters (FAAEs) mainly produced via transesterification reactions among triglycerides and short-chain alcohols catalyzed by chemical catalysts (e.g., KOH, NaOH). Lipase-assisted enzymatic transesterification has been proposed to overcome the drawbacks of chemical synthesis, such as high energy consumption, expensive separation of the catalyst from the reaction mixture and production of large amounts of wastewater during product separation and purification. However, one of the main drawbacks of this process is the enzyme cost. In recent years, nano-immobilized lipases have received extensive attention in the design of robust industrial biocatalysts for biodiesel production. To improve lipase catalytic efficiency, magnetic nanoparticles (MNPs) have attracted growing interest as versatile lipase carriers, owing to their unique properties, such as high surface-to-volume ratio and high enzyme loading capacity, low cost and inertness against chemical and microbial degradation, biocompatibility and eco-friendliness, standard synthetic methods for large-scale production and, most importantly, magnetic properties, which provide the possibility for the immobilized lipase to be easily separated at the end of the process by applying an external magnetic field. For the preparation of such effective magnetic nano-supports, various surface functionalization approaches have been developed to immobilize a broad range of industrially important lipases. Immobilization generally improves lipase chemical-thermal stability in a wide pH and temperature range and may also modify its catalytic performance. Additionally, different lipases can be co-immobilized onto the same nano-carrier, which is a highly effective strategy to enhance biodiesel yield, specifically for those feedstocks containing heterogeneous free fatty acids (FFAs). This review will present an update on the use of magnetic iron oxide nanostructures (MNPs) for lipase immobilization to catalyze transesterification reactions for biodiesel production. The following aspects will be covered: (1) common organic modifiers for magnetic nanoparticle support and (2) recent studies on modified MNPs-lipase catalysts for biodiesel production. Aspects concerning immobilization procedures and surface functionalization of the nano-supports will be highlighted. Additionally, the main features that characterize these nano-biocatalysts, such as enzymatic activity, reusability, resistance to heat and pH, will be discussed. Perspectives and key considerations for optimizing biodiesel production in terms of sustainability are also provided for future studies. [ABSTRACT FROM AUTHOR]

Hepatocellular carcinoma (HCC), the fifth most prevalent cancer worldwide, is influenced by a myriad of clinic-pathological factors, including viral infections and genetic abnormalities. This study delineates the synthesis, characterization, and the biological efficacy of iron oxide nanoparticles (Fe3O4) and chitosan-coated iron oxide nanoparticles (Fe3O4-CS) against HCC. Analytical methods confirmed the successful synthesis of both nanoparticles, with Fe3O4-CS demonstrating a smaller, uniform spherical morphology and distinct surface and magnetic properties attributable to its chitosan coating. The prepared materials were analyzed using various techniques, and their potential cytotoxic effects on HepG2 cancer cells line for HCC were investigated. In biological evaluations against HepG2 cells, a notable distinction in cytotoxicity was observed. Fe3O4 showed modest anticancer activity with an IC50 of 383.71 ± 23.9 µg/mL, whereas Fe3O4 exhibited a significantly enhanced cytotoxic effect, with a much lower IC50 of 39.15 ± 39.2 µg/mL. The Comet assay further evidenced Fe3O4-CS potent DNA damaging effect, showcasing its superior ability to induce apoptosis through extensive DNA fragmentation. Biochemical analyses integrated into our results reveal that Fe3O4-CS not only induces significant DNA damage but also markedly alters oxidative stress markers. Compared to control and Fe3O4-treated cells, Fe3O4-CS exposure significantly elevated levels of oxidative stress markers: superoxide dismutase (SOD) increased to 192.07 U/ml, catalase (CAT) decreased to 0.03 U/L, glutathione peroxidase (GPx) rose dramatically to 18.76 U/gT, and malondialdehyde (MDA) levels heightened to 30.33 nmol/gT. These results underscore the potential of Fe3O4-CS nanoparticles not only in inducing significant DNA damage conducive to cancer cell apoptosis but also in altering enzymatic activities and oxidative stress markers, suggesting a dual mechanism of action that may underpin their therapeutic advantage in cancer treatment. Our findings advocate for the further exploration of Fe3O4-CS nanoparticles in the development of anticancer drugs, emphasizing their capability to trigger oxidative stress and enhance antioxidant defense mechanisms. [ABSTRACT FROM AUTHOR]

Background: The general sluggish clearance kinetics of functional inorganic nanoparticles tend to raise potential biosafety concerns for in vivo applications. Renal clearance is a possible elimination pathway for functional inorganic nanoparticles delivered through intravenous injection, but largely depending on the surface physical chemical properties of a given particle apart from its size and shape. Results: In this study, three small-molecule ligands that bear a diphosphonate (DP) group, but different terminal groups on the other side, i.e., anionic, cationic, and zwitterionic groups, were synthesized and used to modify ultrasmall Fe3O4 nanoparticles for evaluating the surface structure-dependent renal clearance behaviors. Systematic studies suggested that the variation of the surface ligands did not significantly increase the hydrodynamic diameter of ultrasmall Fe3O4 nanoparticles, nor influence their magnetic resonance imaging (MRI) contrast enhancement effects. Among the three particle samples, Fe3O4 nanoparticle coated with zwitterionic ligands, i.e., Fe3O4@DMSA, exhibited optimal renal clearance efficiency and reduced reticuloendothelial uptake. Therefore, this sample was further labeled with 99mTc through the DP moieties to achieve a renal-clearable MRI/single-photon emission computed tomography (SPECT) dual-modality imaging nanoprobe. The resulting nanoprobe showed satisfactory imaging capacities in a 4T1 xenograft tumor mouse model. Furthermore, the biocompatibility of Fe3O4@DMSA was evaluated both in vitro and in vivo through safety assessment experiments. Conclusions: We believe that the current investigations offer a simple and effective strategy for constructing renal-clearable nanoparticles for precise disease diagnosis. [ABSTRACT FROM AUTHOR]

The utilization of metals and metal oxides as photocatalysts is a common method for treating dye contamination. Titanium dioxide nanoparticles (TNPs) are well known for their effectiveness as a photocatalyst in ultraviolet regions, while the inclusion of silver nanoparticles (AgNPs) can improve the photocatalytic properties of the nanocomposite materials in visible light. However, the TNPs and AgNPs are difficult to collect for reuse in water treatment due to their limited dispersion. Henceforth, this work recommended a novel photocatalyst based on hydrotalcite Mg−Al, magnetic Fe3O4 nanoparticles (FNPs), AgNPs, and TNPs prepared using the co‐precipitation method. Additionally, organic silane was first time used as a coupling agent to combine the components together. Consequently, the obtained products were applied for the degradation of methylene blue (MB) under natural sunlight. The characteristics of the synthesized nanocomposites were determined using infrared spectroscopy, vibrating‐sample magnetometer, X‐ray diffraction, dynamic light scattering, and scanning electron microscopy methods. The degradability of MB under sunlight was investigated using ultraviolet‐visible method. Moreover, the antibacterial activity and cytotoxicity of these nanocomposites has been tested and discussed. [ABSTRACT FROM AUTHOR]

Fe3O4 magnetite nanoparticles (MNPs) were prepared using the co-precipitation method at room temperature. The MNPs were modified by coating with SiO2 and APTES to enhance their efficiency for protein detection applications. The MNPs were characterized by Transmission Electron Microscopy (TEM), Scanning Electron Microscopy with Energy Dispersive X-ray spectroscopy (SEM/EDXS), Fourier Transform Infrared (FT-IR), Thermogravimetry Analysis (TGA), X-ray diffraction (XRD), and Vibrating Sample Magnetometer (VSM). The results indicated differences in the size of particles, as around 10-40 nm and there was observed agglomeration among the sample, which, according to SEM image. Moreover, FT-IR analysis confirmed the presence of silica and NH2 coating on the magnetic nanoparticle surface. The immobilization of amine molecules (-NH2) onto the SiO2 surface is evident in TGA. The crystalline structure of the MNPs was identified as the cubic inverse spinel structure of pure-phase polycrystalline magnetite through XRD. Results from the vibrating sample magnetometer (VSM) revealed that the prepared MNPs exhibited a high magnetization saturation (Ms) of 61.31 emu/g and a coercive field strength (Hc) of 30.94 Oe (near ferromagnetism). After being surface modification with SiO2, Ms reduced to 43.24 emu/g, which further decreased to 40.17 emu/g following modification with APTES. Additionally, the Bradford assay was used to measure the percentage binding for BSA, assessing the efficiency of protein detection application. [ABSTRACT FROM AUTHOR]

Radiofrequency ablation is a nominally invasive technique to eradicate cancerous or non-cancerous cells by heating. However, it is still hampered to acquire a successful cell destruction process due to inappropriate RF intensities that will not entirely obliterate tumorous tissues, causing in treatment failure. In this study, we are acquainted with a nanoassisted RF ablation procedure of cardiac tumor to provide better outcomes for long-term survival rate without any recurrences. A three-dimensional thermo-electric energy model is employed to investigate nanothermal field and ablation efficiency into the left atrium tumor. The cell death model is adopted to quantify the degree of tissue injury while injecting the Fe3O4 nanoparticles concentrations up to 20% into the target tissue. The results reveal that when nanothermal field extents as a function of tissue depth (10 mm) from the electrode tip, the increasing thermal rates were approximately 0.54362%, 3.17039%, and 7.27397% for the particle concentration levels of 7%, 10%, and 15% compared with no-particle case. In the 7% Fe3O4 nanoparticles, 100% fractional damage index is achieved after ablation time of 18 s whereas tissue annihilation approach proceeds longer to complete for no-particle case. The outcomes indicate that injecting nanoparticles may lessen ablation time in surgeries and prevent damage to adjacent healthy tissue. [ABSTRACT FROM AUTHOR]

Water contamination caused by hexavalent chromium [Cr(VI)] ions has attracted interest since Cr(VI) ions are highly poisonous and carcinogenic, posing major health risks. We report a simple and efficient approach for preparing Fe3O4 nanoparticles and Fe3O4/NiO composite using the chemical co-precipitation method for Cr(VI) removal. The produced magnetic adsorbents could be readily isolated from the solution using an external magnet and were used for Cr(VI) ion adsorption. The adsorbents were characterized by XRD, VSM, FT-IR, FE-SEM, EDX, and BET analyses. The Langmuir type 1 isotherm provided a good representation of the adsorption data when the Langmuir, Freundlich, Temkin, Harkins–Jura, Hasley, and Redlich-Peterson models were utilized to analyze the adsorption isotherm data. The adsorption capacities of Fe3O4 and Fe3O4/NiO composite calculated from the Langmuir type 1 model were 96.15 mg g−1 and 150 mg g−1, respectively. The saturation magnetization of Fe3O4 and Fe3O4/NiO composite was 60.54 emu/g and 11.09 emu/g, respectively. Both adsorbents may be easily and quickly separated from tainted water by an external magnetic field. According to the findings, both adsorbents are possibly reusable adsorbents for Cr(VI) adsorption. The main advantage of the material is that, due to its magnetic nature, it is easily separated from the adsorbate and may thus be used efficiently in sorption studies. As a result, this magnetic adsorbent provides a viable solution for the successful management of chromium-containing wastewater. [ABSTRACT FROM AUTHOR]

Herein, TiO2 single-tube (TiO2 ST-NT) powders with and without magnetite Fe3O4 nanoparticles (TiO2 ST-NT@Fe3O4NPs) are presented for the first time as excellent photocatalysts for the degradation of one of the most popular non-steroidal anti-inflammatory drugs (NSAIDs), naproxen (NPX). The TiO2 ST-NT powders were synthesized by anodization followed by etching of the double wall, bending, sonication, ultra-centrifugation, and finally annealing at 600°C. A part of the obtained TiO2 ST-NT powders was decorated with Fe3O4 nanoparticles using a simple one-step decoration process. The best photocatalytic performance of TiO2 ST-NT and TiO2 ST-NT@Fe3O4NPs powders was obtained under the white light (6.2 x 10-4 s-1) and the blue light (2.7 x 10-4 s-1), respectively. During NPX photodegradation using TiO2 ST-NT powders, three main NPX transformation products (P1, P2, and P3) were detected. Upon excitation with the blue light illumination, TiO2 ST-NT@ Fe3O4NPs powders exhibited higher performance (~80%) than TiO2 ST-NT powders (~23%) within 1 h, resulting in an approximately three times increased photocatalytic rate constant. Moreover, under simulated sunlight conditions, TiO2 ST-NT powders demonstrated remarkable activity, achieving a 94% NPX degradation within 1 h. TiO2 ST-NT and TiO2 ST-NT@Fe3O4NPs powders represent excellent photocatalysts for NPX degradation. [ABSTRACT FROM AUTHOR]

Standard purification systems have mainly demonstrated the inefficient removal of neonicotinoid insecticides with high persistence in the environment. In the present work, a new magnetic adsorbent composed of Fe3O4 and CuO nanoparticles impregnated with activated carbon (AC) has been used to remove imidacloprid (IMCP) as the most common neonicotinoid insecticide from the water solutions. Various techniques such as Fourier Transform infrared spectroscopy, x-ray diffraction, field emission scanning electron microscopy, energy-dispersive x-ray diffraction, and vibrating sample magnetometer were employed to characterise the fabricated composite. The main affecting parameters, including adsorbent amount, solution pH, agitating time, initial pesticide concentration, and temperature, were examined to obtain the optimised conditions. According to the obtained results from kinetic and isotherm modelling, the adsorption mechanism of IMCP on Fe3O4/CuO@AC nanocomposite (NC) is a combination of chemisorption and physisorption phenomena. The presence of heterogeneous sites for IMCP adsorption was shown by fitting the experimental data to the Freundlich isotherm model. In addition, the adsorption process was well consistent with the pseudo-second-order kinetic model, which indicates that chemisorption is the determining step in the adsorption process. Thermodynamic data showed the exothermic and spontaneous nature of the adsorption process. Under optimal conditions (initial concentration of pesticide 10 mg L−1, pH = 7, and contact time of 10 min), 99.6% of IMCP was effectively removed, indicating the excellent ability of the adsorbent to adsorb this insecticide from aqueous solutions. [ABSTRACT FROM AUTHOR]

A multicomponent reaction (MCR) for the synthesis of five novel N'-(6-chloroquinoxalin-2-yl) benzohydrazide derivatives in excellent yields at room temperature have been achieved via a reaction between 1-(6-chloroquinoxalin-2-yl) hydrazine was added 4-chloroethyl benzoyl chloride followed by the addition of Fe3O4 nanoparticles. This was applied as an efficient and recoverable nanocatalyst for the one‐pot synthesis of hydrazine Derivatives. The catalyst was magnetically recovered and reused for 4 consecutive cycles without significant loss of its activity and selectivity. Fe3O4 Nano catalyst was prepared by the co-precipitation method and characterized by X-ray diffraction (XRD), FT-IR, TEM, VSM, and analyses. This study presents an efficient multicomponent protocol, which provides several advantages, such as short reaction times, high yields, and easy working up this work. [ABSTRACT FROM AUTHOR]

In this work, a novel polycarbonate (PC) nanocomposite membrane was prepared by incorporation of iron oxide (Fe3O4) nanoparticles using the nonsolvent induced phase separation method. The prepared membranes was applied in a submerged membrane system for bovine serum albumin (BSA) filtration through two cycles of 60 min. The properties and performance of fabricated membranes was characterized using water content, porosity, water contact angle, mechanical and thermal properties, membrane morphology including FESEM and AFM, antifouling performance, and BSA rejection. Results showed that by incorporation of Fe3O4 up to 0.5 wt.% in membrane, the hydrophilicity and porosity was increased and then decreased again by more nanoparticles concentration. DSC analysis indicated that Tg of membrane increased from 135.2 to 140.1°C when 0.5 wt.% of Fe3O4 was used. Also, the results of FESEM images revealed that addition of Fe3O4 nanoparticles significantly increased the number and pore size of membrane surface. According to AFM analysis, the membrane containing 0.5 wt.% showed smoother surface as compared to other membranes. Additionally, the PC/Fe3O4–0.5 membrane had better antifouling properties in term of high flux recovery ratio of 82.3% and 85% in the first and second cycles, respectively, while the neat PC membrane showed lower FRR of 70.4% and 74%. [ABSTRACT FROM AUTHOR]

Water-based nanolubricants are widely used in rolling processes due to their unique characteristics. As a common additive, nanoparticles could significantly improve the tribological properties of the lubricant. However, the effect of the physical properties of the particles on the anti-friction behavior is unclear. In this study, the effect of Fe3O4 nanoparticles as an additive for the prepared lubricant is studied. The tribological properties of Fe3O4 water-based nanolubricant are examined using a tribometer and a scratch meter. The absorption energy is calculated using the molecular dynamic simulation method, and the best parameters for the preparation of the nanolubricant are obtained. The developed nanolubricant is used in the rolling process. The results show that the processing quality of samples is promoted and the tribological properties of water-based lubricant can be significantly promoted by an Fe3O4 nanoparticle additive. An economical and environmentally friendly method is presented through which the water-based Fe3O4 nanolubricant can be prepared for the replacement of oil-based lubricant in cold rolling strips. [ABSTRACT FROM AUTHOR]