Superparamagnetic Behavior Research Articles

Tuning the physical properties of ternary alloys (NiCuCo) for in vitro magnetic hyperthermia: experimental and theoretical investigation

Most of published research on magnetic hyperthermia focused on iron oxides, ferrites, and binary alloy nanostructures, while the ternary alloys attracted much limited interest. Herein, we prepared NiCuCo ternary alloy nanocomposites with variable compositions by mechanical alloying. Physical properties were fully characterized by XRD, Rietveld analysis, XPS, SEM/EDX, TEM, ZFC/FC and H-M loops. DFT calculations were used to confirm the experimental results in terms of structure and magnetism. The results showed that the fabricated nanoalloys are face centered cubic (FCC) with average core sizes of 9–40 nm and behave as superparamagnetic with saturation in the range 4.67–42.63 emu/g. Langevin fitting corroborated the superparamagnetic behavior, while law of approach to saturation (LAS) was used to calculate the magnetic anisotropy constants. Heating effciencies were performed under an alternating magnetic field (AMF, H0 = 170 Oe and f = 332.5 kHz), and specific absorption rate (SAR) values were determined. The highest magnetic saturation (Ms), heating potentials, and SAR values were attained for Ni35Cu30Co35 containing the lowest Cu but highest Ni and Co percentages, and the least for Ni15Cu70Co15. Importantly, the nanoalloys reached the required temperatures for magnetic hyperthermia (42 °C) in relatively short times. We also showed that heat dissipiation can be simply tuned by changing many parameters such as concentration, field amplitude, and frequency. Finally, cytotoxicity viability assays against two different breast cancer cell lines treated with Ni25Cu50Co25 nanoalloy in the presence and absence of AMF were investigated. No significant decrease in cancer cell viability was observed in the absence of AMF. When tested against tumorigenic KAIMRC2 breast cancer cells under AMF, the NiCuCo nanoalloy was found to be highly potent to the cells (~ 2-fold enhancement), killing almost all the cells in short times (20 min) and clinically-safe AC magnetic fields. These findings strongly suggest that the as-prepared ternary NiCuCo nanoalloys hold great promise for potential magnetically-triggered cancer hyperthermia.

STRUCTURAL, MORPHOLOGICAL AND MAGNETIC PROPERTIES OF FUNCTIONALIZED MANGANESE IRON OXIDE NANOPARTICLES FOR BIOLOGICAL APPLICATIONS

The chitosan functionalized MnFe2O4 nanoparticles were synthesized using thermal decomposition method. The morphological, structural and magnetic properties of obtained chitosan functionalized magnetic nanoparticles were studied to assess the feasibility for biomedical applications. The crystallite size of nanoparticles observed using XRD was 15nm. Functional group attachment to surface of nanoparticles was analyzed using FTIR. Particle size of nanoparticles was studied by TEM analysis and it showed that particles were roughly spherical. Thermal stability and bonding strength of ligands to the surface of material was determined using TGA. The magnetization of chitosan functionalized nanoparticles observed by VSM is 56emu/g and VSM showed no coercivity and remanence existence, stipulating the super-paramagnetic behavior. The cell viability of chitosan functionalized nanoparticles was above 85% at concentration up to the 1.0mg mL-1 on mouse fibroblast cell line i.e. L929 cell line. These studies revealed that, MnFe2O4 nanoparticles are potential materials for biomedical applications.

Supraparticles from Cubic Iron Oxide Nanoparticles: Synthesis, Polymer Encapsulation, Functionalization, and Magnetic Properties.

Supraparticles (SPs) consisting of superparamagnetic iron oxide nanoparticles (SPIONs) are of great interest for biomedical applications and magnetic separation. To enable their functionalization with biomolecules and to improve their stability in aqueous dispersion, polymer shells are grown on the SPs' surface. Robust polymer encapsulation and functionalization is achieved via atom transfer radical polymerization (ATRP), improving the reaction control compared to free radical polymerizations. This study presents the emulsion-based assembly of differently sized cubic SPIONs (12-30 nm) into SPs with diameters ranging from ∼200 to ∼400 nm using dodecyltrimethylammonium bromide (DTAB) as the surfactant. The successful formation of well-defined spherical SPs depends upon the method used for mixing the SPION dispersion with the surfactant solution and requires the precise adjustment of the surfactant concentration. After purification, the SPs are encapsulated by growing surface-grafted polystyrene shells via activators generated by electron transfer (AGET) ATRP. The polymer shell can be decorated with functional groups (azide and carboxylate) using monomer blends for the polymerization reaction. When the amount of the monomer is varied, the shell thickness as well as the interparticle distances between the encapsulated SPIONs can be tuned with nanometer-scale precision. Small-angle X-ray scattering (SAXS) reveals that cubic SPIONs form less ordered assemblies within the SPs than spherical SPIONs. As shown by vibrating sample magnetometer measurements, the encapsulated SPs feature the same superparamagnetic behavior as their SPION building blocks. The saturation magnetization ranges between 10 and 30 emu/g and depends upon the nanocubes' size and phase composition.

Effective removal of Pb(II) ions using Fe3O4/MgO adsorbent: A comprehensive study  

The effective removal of heavy metal ions, particularly Pb(II), from contaminated water sources remains a pressing environmental concern. This study explores the potential of Fe3O4/MgO nanocomposites as an efficient adsorbent for selective Pb(II) removal. The Fe3O4/MgO nanocomposite was synthesized using a controlled sol-gel method and characterized using various techniques. X-ray diffraction (XRD) analysis confirmed the presence of cubic MgO and cubic Fe3O4. Pb(II) adsorption induced a crystallographic transformation, forming hexagonal Mg(OH)2 crystals, indicating interaction with the adsorbent. Scanning Electron Microscope (SEM) analysis revealed pyramid-like and irregular crystal morphologies. Pyramid-like structures provided a larger surface area and active sites for effective Pb(II) interaction, while irregular crystal particles, representing magnetic Fe3O4, contributed to stability and dispersibility. Vibrating sample magnetometer (VSM) results confirmed superparamagnetic behaviour with a saturation magnetization of 32.02 emu g-1, indicating potential for magnetic separation and recovery in various wastewater treatment applications. Adsorption experiments utilized optimized conditions: an initial concentration of 600 mg L-1, adsorbent dosage of 0.25 g L-1, pH of 7, and 120 minutes of reaction time. The Fe3O4/MgO nanocomposite exhibited exceptional performance with a remarkable 99.98% removal efficiency and a high adsorption capacity of 2399.44 mg g-1. These impressive results underscore the outstanding adsorption potential of the nanocomposite. Adsorption kinetics followed the pseudo-second-order model (R2 = 0.99), confirming suitability for Pb(II) removal. The Freundlich model indicated a heterogeneous surface with different adsorption sites. Overall, the Fe3O4/MgO nanocomposite exhibits potential as a cost-effective, environmentally friendly adsorbent for removing Pb(II) ions, providing a promising solution for water purification and environmental remediation.

Quantitative Analysis of Ferrate(VI) and Its Degradation Products in Electrochemically Produced Potassium Ferrate for Waste Water Treatment

Potassium ferrate(VI) (K2FeO4) as a particularly strong oxidant represents an effective and environmentally friendly waste water treatment material. When produced by anodic oxidation in highly alkaline aqueous solution, the K2FeO4 product is separated and sealed in inert plastic bags with the retention of some liquid phase with high pH. This method proved to be excellent for long-term storage at moderately low temperature (5 °C) for industrial applications. It is still imperative to check the ferrate(VI) content of the product whenever it is to be used. Fe-57 Mössbauer spectroscopy is an excellent tool for checking the ratio of ferrate(VI) to the degradation product iron(III) in a sample. For this purpose, normally the spectral areas of the corresponding subspectra are considered; however, this approximation neglects the possible differences in the corresponding Mössbauer–Lamb factors. In this work, we have successfully determined the Mössbauer–Lamb factors for the ferrate(VI) and for the most common iron(III) degradation products observed. We have found superparamagnetic behavior and low-temperature phase transformation for another iron(III) degradation product that made the determination of the Mössbauer–Lamb factors impossible in that case. The identities of a total of three different iron(III) degradation products have been confirmed.

Green Chemical Synthesis of Cube‐Shaped CuFe2O4 Nanoparticles for Use as Magnetically Retrievable Catalysts in A3 Coupling Reactions

ABSTRACTA3 coupling reaction is a multicomponent reaction (MCR) involving aryl aldehydes, phenyl acetylenes and amines to synthesize a variety of biologically active propargylamine derivatives. Herein, we report the preparation of cube‐shaped CuFe2O4 nanoparticles (NPs) via the hydrothermal method in the presence of Lantana camara flower (LCF) extract to use them as catalysts to synthesize propargylamine derivatives. X‐ray diffraction study confirms the formation of CuFe2O4 NPs with cubic spinel structures. In the presence of LCF extract, cube‐shaped CuFe2O4 NPs are formed predominantly irrespective of the type of alkali used as the hydrolyzing agent. However, a mixture of nearly spherical and cube‐shaped particles has been formed in the absence of additives. The synthesized CuFe2O4 NPs exhibit superparamagnetic behaviour and are magnetically ordered. The synthesized cube‐shaped CuFe2O4 NPs exhibit excellent catalytic activity in the A3 coupling reaction between benzaldehyde, piperidine and phenylacetylene to give propargylamine with a yield of 90% under the optimum conditions. The catalyst is highly stable and magnetically retrievable facilitating reusability for up to five cycles without considerable loss of catalytic activity. The protocol is suitable for the synthesis of a diverse range of propargylamine derivatives with moderate to excellent yield.

Synthesis, Magnetic, and Photocatalytic Activity of Polypyrrole-Based TiO2–Fe Catalyst for Wastewater Treatment

The primary aim of this study is to investigate the degradation efficacy of the Ppy/TiO2-Fe photocatalyst for MB dye in an aqueous solution. Firstly, the direct addition of TiO2 and Fe was done to prepare Ppy/TiO2-Fe photocatalyst. Fourier transformation infrared spectroscopy, XRD, SEM, BET surface area analysis, and magnetization tests established the formation of the Ppy/TiO2-Fe photocatalyst. The crystallite sizes of TiO2, Fe-TiO2, and Ppy/TiO2-Fe photocatalyst were estimated to be 24.99 nm, 21.94 nm, and 21.84 nm, respectively. For the synthesis confirmation, the FTIR spectrum confirmed the existence of Ti-O, Fe-O, and Ppy-related bonds. While comparing the SEM images, the impact of polypyrrole on the particle shape was observed with less aggregation and increased surface roughness. The VSM analysis revealed that incorporating polypyrrole (Ppy) into Fe-TiO2 significantly enhances its magnetic properties, with Ppy/TiO2-Fe exhibiting superparamagnetic behavior, characterized by a higher saturation magnetization (Ms) of 33.11 emu/g and a lower coercivity (Hc) of 0.160 Oe, compared to Fe-TiO2’s Ms of 1.09 emu/g and Hc of 341.39 Oe. The N2 sorption desorption, with a specific surface area of 2.25 × 102 m2/g, is beneficial for photocatalytic activity. The concentration of dye, amount of catalyst, pH, and temperature were studied to evaluate the photocatalytic efficiency of the synthesized Ppy/TiO2-Fe photocatalyst under different conditions. The findings revealed a degradation efficiency of 91.92%. The degradation rate reached 91.92% under optimal conditions within 120 min and could be fitted well by first-order kinetics. The photocatalytic efficiency was also evaluated for the scavenger, and the concentration of H2O2 and the reusability of the catalyst were demonstrated. Based on the observed results, the Ppy/TiO2-Fe photocatalyst could be applied more effectively and efficiently to photocatalytic degradation of organic dyes in wastewater treatment.

A New Powerful Magnetic Dark Catalyst Based on rGO/Fe3O4/CdSe Nanocomposite for Ultrafast Degradation of Methylene Blue Dye.

In the present study, Rgo/Fe3O4/CdSe as a dark catalyst material was synthesized by a refluxing method. The synthesized magnetic nanocomposites were studied by various analyses such as Fourier transform infrared (FTIR), energy-dispersive X-ray spectroscopy (EDS), field emission scanning electron microscopy (FESEM), X-ray diffractometer (XRD), Raman, Zeta and vibrating sample magnetometer (VSM). Characterization of structural analysis showed that the nanocomposites were successfully synthesized. The absorption spectrum was used to determine the dark catalyst activity of rGO/Fe3O4/CdSe nanocomposite. Analysis of the absorption spectrum showed that the prepared nanocomposites degrade the MB organic dye completely (100%) after 2min of stirring in the dark, also experimenting with different pH showed that the best performance for the degradation of MB occurs in neutral and alkaline media. The Raman spectrum analysis showed that the Fe3O4/CdSe quantum dots (QDs) were correctly incorporated on the reduced graphene oxide (rGO) nanosheets. Zeta potential analysis showed that rGO/Fe3O4/CdSe has a large amount of negative charge on its surface and the surface charge increased by about 16 mV compared to the Fe3O4/CdSe compound. BET and BJH techniques were used to determine the effective surface area and pore size diameter, BET results to determine the effective surface area showed that by adding graphene to the compound, the specific surface area increased from 42.877 m2g-1 to 54.1896 m2g-1. The radical scavenger experiment showed that electrons play an essential role in the degradation process. VSM analysis showed that the prepared nanocomposites have excellent superparamagnetic behavior, this advantage enables the easy collection of nanocatalysts by magnets from wastewater after dye degradation.

A structural, magnetic and colloidal stability study of uncoated and silica coated iron oxide samples prepared in two different surfactants

The discovery of new magnetic materials of interest in the biomedicine field is a relevant topic in current research. For years, our research group has been investigating the obtaining and study of nanostructured magnetic samples that behave superparamagnetically to enable their transport in living organisms. We present here a study that summarizes the structural characteristics, magnetic behavior and stability of two Fe3O4 samples synthesized by coprecipitation that were dispersed using two different surfactants (oleylamine, OL, and oleic acid, OA), and two others prepared from the previous ones by reaction with tetraethyl orthosilicate (TEOS). The relationships between the surfactant used in the synthesis, the presence of a certain maghemite (γ-Fe2O3) content, the influence of silica shell thickness and magnetic behaviour of all samples were systematically studied by X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), transmission electron microscopy (TEM), Mössbauer spectroscopy and H vs. M loops. Rietveld refinements of the XRD profiles confirmed a partial oxidation of the non-silica-coated samples and FTIR spectra of the uncoated samples showed a very strong broad metal-oxygen band and additional sets of bands from the different organic chains of the two surfactants. Individual particles with a mean diameter of 7 and 9 nm were distinguished in TEM images of uncoated magnetic samples. Mössbauer data indicated the presence of non-stoichiometric magnetite in all samples, in agreement with XRD refinements. Magnetic measurements confirmed the superparamagnetic behavior of all the samples. Highest negative zeta potential values are found for the silica covered samples in both acidic and basic medium, being Fe3O4-AO@SiO2 the best suited for the purposes of its dispersibility in future applications. Low polydispersity index (PDI) values confirmed the best stability and dispersibility of all samples investigated in tetrahydrofuran (THF).

Optimization of Magnetite Nanoparticles for Magnetic Hyperthermia: Correlation with Physicochemical Properties and Cation Distribution

AbstractThe present study reveals the synthesis of Iron oxide nanoparticles (IONPs) by varying the molar ratio of ferric (Fe3+) to ferrous (Fe2+) ions via chemical coprecipitation method for the study of cationic distribution of Fe‐ions and its potential application for magnetic hyperthermia therapy (MHT). X‐ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), Fourier transform infrared spectroscopy (FTIR), and X‐ray photoelectron spectroscopy (XPS), were used to characterize the physicochemical properties. Several structural parameters were estimated using the Rietveld refinement, resulting in structural modelling verified by magnetic characteristics. A vibrating sample magnetometer (VSM) assessed the magnetic hysteresis loop at room temperature in a field range of ±15 kOe, revealing superparamagnetic behavior for the ratio Fe2+/Fe3+ 1:2. The saturation magnetization (Ms) of IONPs increased with the increasing Fe2+ concentration and attained a maximum value of 60.21 emu g−1 at a molar ratio of 2:1. The potential of the inductive heating capability of IONPs in an alternating current magnetic field (AMF) was studied to treat localized MHT. The changes in magnetic properties and inductive heating properties of IONPs are associated with the cationic distribution of Fe2+ at the tetrahedral (A) and octahedral (B) sites of crystal structure. The variation in cationic properties at the A and B sites may result in varying/tuneable magnetic properties, affecting the overall heating profiles of hyperthermia.

Structural, Morphology and Electromagnetic Interference Shielding Studies of Multifunctional Hybrids of Low-Density Polyethene with Graphene, Carbon Nanotube and Magnetite

ABSTRACT In this study, we investigate the EMI SE (Electromagnetic interference shielding effectiveness) of novel multifunctional polymer hybrids in the X-band and Ku-band frequencies. Magnetite nanoparticles were synthesized via wet chemical reduction and nanographene was synthesized through chemical exfoliation combined with microwave treatment. Nine different composites were prepared with varying weight ratios of graphene and magnetite. X-ray diffraction (XRD) and scanning electron microscopy (SEM) confirmed their structural and morphological properties. SEM analysis revealed magnetite particle sizes ranging from 10.05 nm to 29.8 nm. Vibrating Sample Magnetometer (VSM) analysis indicated that the magnetite nanoparticles exhibit super paramagnetic behavior with a magnetic anisotropy constant (K) of approximately 63.9375 × 106 J/m3. Impedance analysis, permittivity and permeability measurements showed frequency-dependent behaviors, with interfacial polarization effects due to magnetite agglomeration. The highest conductivity, observed in the 50:5:37.5:7.5 hybrid, peaked at 8 S/cm at lower frequencies. The 50:5:37.5:7.5 hybrid demonstrated the highest EMI SE of 50.08 dB (99.999019% suppression) in the X-band, which is suitable for advanced EMI-shielding applications.

Unraveling the properties of [TPA]2Cu2Br6: A holistic investigation into structure, optics, magnetism and dielectric characteristics

The recent technological advances require an aligned innovation in the materials used for the construction of electronic devices. Hybrid materials play a important role in the optoelectronic applications because they combine both the organic and inorganic components To this end, the [TPA]2Cu2Br6 compound was successfully synthesized using the slow evaporation solution growth approach at room temperature. The [TPA]2Cu2Br6 compound crystallizes in the triclinic system with P1‾space group. The atomic arrangement can be described by an alternation of organic and inorganic layers stacked along the c direction and made up of [N(C3H7)4]+ and [CuBr3]− groups, respectively. The examination of SEM analysis allows us to raise the morphology and the good quality of the crystals. The EDX analysis was performed to ensure that all chemical elements were discovered and located in the relevant locations.For the compound under study, the UV–visible spectroscopy spectrum shows the direct band-gap value of ∼3.52 eV, indicating that it is a semiconductor material. Magnetic measurements revealed the superparamagnetic behavior. Studies of the dielectric constant permittivity ε*(ω) confirmed that the relaxation process was thermally activated. The dominant transport mechanism is the s the non-overlapping small polaron tunneling (NSPT) model.

Evaluation of magnetic hyperthermia, drug delivery and biocompatibility (bone cell adhesion and zebrafish assays) of trace element co-doped hydroxyapatite combined with Mn-Zn ferrite for bone tissue applications.

The treatment and regeneration of bone defects, especially tumor-induced defects, is an issue in clinical practice and remains a major challenge for bone substitute material invention. In this research, a composite material of biomimetic bone-like apatite based on trace element co-doped apatite (Ca10-δ M δ (PO4)5.5(CO3)0.5(OH)2; M = trace elements of Mg, Fe, Zn, Mn, Cu, Ni, Mo, Sr and BO3 3-; THA)-integrated-biocompatible magnetic Mn-Zn ferrite ((Mn, Zn)Fe2O4 nanoparticles, BioMags) called THAiBioMags was prepared via a co-precipitation method. Its characteristics, i.e., physical properties, hyperthermia performance, ion/drug delivery, were investigated in vitro using osteoblasts (bone-forming cells) and in vivo using zebrafish. The synthesized THAiBioMags particles revealed superparamagnetic behaviour at room temperature. Under the influence of an alternating magnetic field, THAiBioMags particles demonstrated a change in temperature, indicating their potential for magnetic hyperthermia, in which THAiBioMags further exhibited a specific absorption rate (SAR) value of 9.44 W g-1 (I = 44 A, H = 6.03 kA m-1 and f = 130 kHz). In addition, the as-prepared particles demonstrated sustained ion/drug (doxorubicin (DOX)) release under physiological pH conditions. Biological assay analysis revealed that THAiBioMags exhibited no toxicity towards osteoblast cells and demonstrated excellent cell adhesion properties. In vivo studies employing an embryonic zebrafish model showed the non-toxic nature of the synthesized THAiBioMags particles, as revealed by evaluation of the survivability, hatching rate, and embryonic morphology. These results could potentially lead to the design and fabrication of magnetic scaffolds to be used in therapeutic treatment and bone regeneration.

Photocatalytic degradation of rhodamine B using Yb3+-Doped Zn-Mg ferrites synthesized via conventional sol-gel auto-combustion method

The primary goal of our research is to develop a photocatalyst capable of degrading organic molecules in water, achieved through the rare earth Yb3+ doping of Zn-Mg spinel ferrites. A key element of our approach is the use of the conventional sol-gel auto-combustion process, which has proven to be an effective method for synthesizing a high-performing, visible light-driven Zn0.9Mg0.1Fe2-xYbxO4 (x = 0.000, 0.015, 0.030, 0.045, 0.060 and 0.075) nano-ferrites. Many analytical techniques were employed to evaluate the material's physicochemical characteristics, including P-XRD, EDX, FE-SEM, HR-TEM, FTIR, UV–vis, BET, VSM, EIS, and photocatalysis was carried out against the RhB. The impact of Yb3+ ion doping on the material's crystallite size and lattice parameter has been evaluated. It was found that all the samples' crystallite sizes increased between 33 and 41 nm. These magnetite nanoparticles have spherical forms and nanometric particle sizes, as revealed through field scanning electron microscopy (FE-SEM). The FTIR spectra bands at ʋ1 (518–535) and (401–411) ʋ2 subsequently revealed the spinel structure of the synthesized nano-ferrites. The band gap in zinc manganese ferrite increases from 2.51 eV to 2.92 eV after adding ytterbium. The surface area of the Yb3+-doped Zn-Mg ferries ranges from 23.6 m2/g to 27.8 m2/g, making them an excellent choice for data storage. The investigation of magnetic behavior shows the superparamagnetic behavior of all the samples. The produced sample's determined squareness value indicates the magnetostatic interaction between the particles. Because of the low produced coercive field value, these materials can be used in ferrofluids and hyperthermia therapy applications. Furthermore, with a higher RhB removal of 93.80 %, the Yb3+-doped sample photocatalyst successfully separated carriers generated by sunlight. The Yb3+-doped sample (ZMY-5) photocatalyst showed outstanding stability after one cycle of the stability test, obtaining an outstanding RhB elimination of 93.80 %. Zn0.9Mg0.1Yb0.075Fe1.925O4 photocatalyst has substantial promise for large-scale pollutant treatment due to its simple synthesis method, superior magnetic characteristics, exceptional photocatalytic activity for RhB, and excellent stability.

A Theoretical Study on the Magnetic Features of Ru2MnX Nano-Heusler Alloys

This study focuses on examining magnetic property performances among three nano-Heusler Ru2MnX alloys (where X is replaced by the atoms V, Ta and Nb). The investigation was conducted through Monte Carlo simulations, exploring the magnetic properties of these alloys. The study established a clear transition from ferrimagnetic to superparamagnetic behavior. Furthermore, it exposed the effects of magnetization in each nano-Heusler alloy relative to physical factors.

Engineered hybrid iron‐cobalt metal oxide nanoparticles for effective adsorption of malachite green dye

AbstractBACKGROUNDHybrid iron and cobalt metal oxide nanoparticles are well known; however, are not optimized in terms of size and stability. We engineered these hybrid nanoparticles using the co‐precipitation method and characterized them by various techniques, which are then used for the effective adsorption and removal of malachite green (MG) dye.RESULTSThe ideal conditions for synthesis are determined to be 50:50 ratio of Fe2O3 and CoO, pH of 11, temperature range of 40 °C–60 °C, and reactant addition time of 20 min. These hybrid nanoadsorbents effectively eliminated MG dye from aqueous solutions. Factors such as initial MG dye concentration, pH of the medium, contact time, temperature, and nanoadsorbent dose were optimized for the MG removal to achieve a maximum removal efficiency of 96.9%. Non‐linear fitting of data indicates that both Langmuir and Freundlich models provided the best fit, suggesting the presence of both monolayer and multilayer adsorption of MG on hybrid nanoparticles. The kinetics of MG dye removal are better controlled by the intraparticle diffusion (IPD) phenomenon. The adsorption of MG onto the hybrid nanoparticles was confirmed to be endothermic, with negative ΔG and positive ΔH values. The optimized synthetic conditions also positively impacted the hybrid nanoparticles which enhanced the adsorption and exhibited ferromagnetic behavior as compared to the superparamagnetic behavior reported in the literature, making them significantly important for dye removal applications.CONCLUSIONThese findings demonstrate the potential of optimized hybrid nanoparticles as effective nanoadsorbents for dye removal applications, with implications for further applications in photocatalysis and sensing. © 2024 Society of Chemical Industry (SCI).

Magnetic, structural, and morphological properties behavior of Ni1–xCoxFe2O4 magnetic nanoparticles: Theoretical and experimental study

In this work, we synthesized nanoparticles of the Ni1-xCoxFe2O4 (with x = 0.25, 0.50, and 0.75) inverse spinel by the hydrothermal method. Scanning transmission electron microscopy (STEM) analysis and elemental characterization revealed the formation of nanoparticles of the order of ∼3 nm with a homogeneous distribution of their constituents, denoting the correct material synthesis. The results show that as the content of Co2+ increases, the cell parameter of the structures increases and the crystallite size increases. Besides, the magnetic characterization exhibits an increase in the saturation magnetization as the Co2+ content moves from x = 0.25 to x = 0.75, on the other hand, the coercive field decreases, which is attributed to the superparamagnetic behavior of the structures. By Density Functional Theory (DFT) calculation demonstrates that the inverse spinel is the most favorable configuration for both NiFe2O4 and CoFe2O4 compounds. Besides, by first-principles thermodynamics, we have shown that Co tends to occupy the Ni sites as the most favorable configuration, with an increase in the cell parameter and total magnetization as Co content increases, in excellent agreement with experimental measurements. Our findings demonstrate that Co-Ni-based ferrites are soft magnetic materials, which are suitable candidates to be employed in devices that require rapid magnetization and demagnetization

Structural, magnetic, and luminescent properties of NaGdF4:Nd3+@Fe3O4 nanocomposites

The diverse applications of nanomaterials, and their rapidly increasing demand, have spurred the development of novel multifunctional materials. As such, this study aimed to synthesize and characterize a magneto-luminescent nanocomposite, composed of magnetite and fluorescent quantum dots (NaGdF4:Nd3+@Fe3O4). Nanomaterial synthesis was accomplished through solvothermal and co-precipitation methods. Stable nanoparticles (NPs) with a zeta potential of -19.57 ± 0.42 mV, and a size of 4.55 ± 1.44 nm were obtained. The crystalline structure of the NPs, verified via x-ray diffraction, affirmed the hexagonal pattern of the NaGdF4:Nd3+NPs and the inverse spinel pattern of Fe3O4NPs. In the diffraction pattern of the NaGdF4:Nd3+@Fe3O4NPs, only the phase pertaining to the Fe3O4NPs was identified, indicating their influence on the nanocomposite. Magnetic measurements revealed the superparamagnetic behavior of the material. Photoluminescence spectra of NaGdF4:Nd3+and NaGdF4:Nd3+@Fe3O4NPs verified the luminescent emission around 1060 nm; a feature of the radiative transitions of Nd3+ions. Based on the assessed characteristics, the nanocomposite's multifunctionality was confirmed, positioning the material for potential use in various fields, such as biomedicine.

Green synthesized Fe3O4@CD nanocomposites using Acacia caesia leaves: In vitro biological properties and cytotoxicity assessment

The aim of the present study is to prepare carbon dots (CDs) from Acacia caesia leaves and use them to synthesize Magnetite@CD (Fe3O4@CD) nanocomposites (NCs). The absorbance spectrum, photoluminescence, and surface functional groups were revealed in the optical and morphological properties analysis, which confirmed the successful formation of Fe3O4@CD NCs. Electron microscopy showed that the NCs had an almost spherical shape, with an average particle diameter of 11.02 nm. A vibrating sample magnetometer (VSM) also confirmed the superparamagnetic behavior of Fe3O4@CD NCs behaved in a superparamagnetic way. This study also observed effective in vitro antioxidant, anti-inflammatory, and cytotoxicity properties, all with low inhibitory concentration 50 (IC50) values. However, neither Candida albicans nor Aspergillus niger showed any potential antifungal activity by both CDs and Fe3O4@CD NCs. The synthesized Fe3O4@CD NCs demonstrate significant potential for biomedical applications due to their superparamagnetic properties and low IC50 values, offering new insights into the design of multifunctional nanocomposites. Tuning the physiochemical properties of nanomaterials can have broad-field scientific applications.

A comparative study of sericin and gluten for magnetic nanoparticle-mediated drug delivery to breast cancer cell lines

With breast cancer emerging as a pressing global health challenge, characterized by escalating incidence rates and geographical disparities, there is a critical need for innovative therapeutic strategies. This comprehensive research navigates the landscape of nanomedicine, specifically focusing on the potential of magnetic nanoparticles (MNPs), with magnetite (Fe3O4) taking center stage. MNPs, encapsulated in biocompatible polymers like silica known as magnetic silica nanoparticles (MSN), are augmented with phosphotungstate (PTA) for enhanced chemodynamic therapy (CDT). PTA is recognized for its dual role as a natural chelator and electron shuttle, expediting electron transfer from ferric (Fe3+) to ferrous (Fe2+) ions within nanoparticles. Additionally, protein-based charge-reversal nanocarriers like silk sericin and gluten are introduced to encapsulate (MSN-PTA) nanoparticles, offering a dynamic facet to drug delivery systems for potential revolutionization of breast cancer therapy. This study successfully formulates and characterizes protein-coated nanocapsules, specifically MSN-PTA-SER, and MSN-PTA-GLU, with optimal physicochemical attributes for drug delivery applications. The careful optimization of sericin and gluten concentrations results in finely tuned nanoparticles, showcasing uniform size, enhanced negative zeta potential, and remarkable stability. Various analyses, from Dynamic Light Scattering (DLS) and scanning electron microscopy (SEM) to transmission electron microscopy (TEM), Fourier Transform Infrared Spectroscopy (FTIR), X-Ray diffraction analysis (XRD), and Thermogravimetric analysis (TGA), provide insights into structural integrity and surface modifications. Vibrating Sample Magnetometer (VSM) analysis underscores superparamagnetic behavior, positioning these nanocapsules as promising candidates for targeted drug delivery. In vitro evaluations demonstrate dose-dependent inhibition of cell viability in MCF-7 and Zr-75–1 breast cancer cells, emphasizing the therapeutic potential of MSN-PTA-SER and MSN-PTA-GLU. The interplay of surface charge and pH-dependent cellular uptake highlights the robust stability and versatility of these nanocarriers in tumor microenvironment, paving the way for advancements in targeted drug delivery and personalized nanomedicine. This comparative analysis explores the suitability of silk sericin and gluten, unraveling a promising avenue for the development of advanced, targeted, and efficient breast cancer treatments.