Superparamagnetic Properties Research Articles

8-Anilino-1-naphthalenesulfonate-Conjugated Carbon-Coated Ferrite Nanodots for Fluoromagnetic Imaging, Smart Drug Delivery, and Biomolecular Sensing

Background: Superparamagnetic properties and excitation independence have been incorporated into carbon-decorated manganese ferrite nanodots (MnFe@C) to introduce an economical and safer multimodal agent for use in both T1-T2 MRI and fluorescence-based imaging to replace the conventional highly toxic heavy metal contrast agents. Methods: The surface conjugation of 8-anilino-1-naphthalenesulfonate (ANS) to MnFe@C nanodots (ANS-MnFe@C) enhances both longitudinal and transverse MRI relaxation, improves fluorescence for optical imaging, and increases protein detection sensitivity, showing higher multimodal efficacy in terms of molar relaxivity, radiant efficiencies, and fluorescence sensitivity compared to MnFe@C. Results: The band gap energy was determined using Tauc’s equation to be 3.32 eV, while a 72% quantum yield demonstrated that ANS-MnFe@C was highly fluorescent, with the linear range and association constant calculated using the Stern–Volmer relation. The synthesized ANS-MnFe@C demonstrated excellent selectivity and sensitivity for bovine serum albumin (BSA), with a nanomolar detection limit of 367.09 nM and a broad linear range from 0.015 to 0.225 mM. Conclusions: In conclusion, ANS-MnFe@C holds ease of fabrication, good biocompatibility, as assessed in A375 cells, and an effective pH-sensitive doxorubicin release profile to establish anticancer activity in lung cancer cell line (A549), highlighting its potential as an affordable therapeutic agent for multimodal imaging, drug delivery, and protein sensing.

Mitoxantrone release from Fmoc-protected amino acids coated magnetic carbon nanotubes: Computational and experimental study for cancer treatment

Nanoparticles have a high potential for use as drug carrier systems in cancer treatment to reduce severe side effects, as in the treatment of many other diseases. Due to their unique properties, carbon-based nanoparticles such as carbon nanotubes (CNTs) are among the most frequently used nanoparticles in drug carrier systems. In this study, magnetic single-walled CNTs (mCNTs) were synthesized, characterized, coated and their ability to carry the anticancer drug mitoxantrone (MTO) was investigated using computational and experimental methods. First, the mCNT coating capabilities of Fmoc-protected amino acids, Fmoc-Cys(trt)-OH and Fmoc-Trp-OH were demonstrated by Raman spectroscopy, thermogravimetric analysis, and X-ray photoelectron spectroscopy. Then, full-atom molecular dynamics simulations of MTO-CNT complexes in explicit water were used to understand Fmoc-amino acid and MTO loading experiments at the molecular level. Binding free energies calculated by the Molecular Mechanics/Poisson-Boltzmann Surface Area method suggested MTO-CNT complex stability even at elevated temperatures up to 350 K that can be achieved due to external magnetic stimuli. Drug loading at pH 9 and releases at physiological (pH 7.4) and lysosomal pH (pH 5.5) were carried out for uncoated and coated mCNTs. The drug release and characterization results showed that coated mCNTs have pH-responsive drug release, enhanced dispersibility, and superparamagnetic properties so they promise to be beneficial for MTO delivery in cancer treatment. Cell viability results demonstrated that the mCNT-Fmoc-Cys samples had higher cell viability compared to the mCNT and mCNT-Fmoc-Trp groups.

Exploring different dopant materials in conjunction with iron oxide and analyzing their characterization and magnetic properties

The comparative studies of pure and different doping materials of α-XFe2O3 (X = Co, Mn, Ni and Zn) nanoparticles in Structural, Morphological, Optical, and magnetic behavior were analyzed in this article. The synthesis of α-XFe2O3 nanoparticles through the Sol-gel method for magnetic properties with various doping materials such as Co, Mn, Ni, and Zn. The structural, morphological, optical, and magnetic properties were carefully examined, revealing enhanced characteristics. XRD studies confirmed the successful incorporation of dopants into the crystal structure of α-Fe2O3, while Morphological analysis through SEM images indicated superparamagnetic properties in Co and Zn doped samples, and ferrite behavior in Mn and Ni doped samples. UV Spectra analysis showed optical transitional changes related to magnetic behavior, and the dielectric effect was attributed to the presence of multiple domains within the sample. The study effectively demonstrated the unique magnetic properties of pure and α-XFe2O3 nanoparticles, highlighting the importance of different doping materials in influencing their characteristics.

Multifunctional 1–octadecanol/expanded graphite/Fe3O4 composite phase change materials with effective solar–to–thermal and magnetic–to–thermal conversion and storage

Composite phase change materials (CPCMs) with multifunctional thermal conversion and storage abilities have demonstrated exceptional properties for diverse energy storage applications recently; however, these composite materials often encounter limitations of low heat storage capacity and high cost. In this study, novel 1–octadecanol (OD)/expanded graphite (EG)/Fe3O4 CPCMs were facilely prepared and characterized for multifunctional thermal conversion and storage properties. The composites showed excellent thermal energy storage capacities, reaching 185.5 J/g at 80 % OD accompanied by high crystallization fractions of above 95 %. In addition, they exhibited great thermal conductivities, excellent leakage resistance, thermal stability, and reliability. Under simulated solar irradiation, the prepared OD/EG/Fe3O4 CPCMs exhibited a rapid temperature increase from 34 to 70 °C, achieving solar–to–thermal conversion efficiency of 80.2–90.5 %. This behavior can be attributed to its ability to capture and convert photons into thermal energy, facilitated by the synergistic effects of the conjugated double–bond system of EG and localized surface plasmon resonance of Fe3O4 nanoparticles. Furthermore, the prepared OD/EG/Fe3O4 CPCMs exhibited superparamagnetic properties, accelerating their temperatures from 32 °C to 88 °C within 11–23 s when subjected to an alternating magnetic field. This demonstrates magnetic–to–thermal conversion and storage ability. These findings highlight the potential of OD/EG/Fe3O4 CPCMs as promising and cost–effective materials for various practical thermal storage applications.

Interparticle interaction effect on superparamagnetic properties of ferrimagnetic particles

Uncoated and oleic acid coated ferrimagnetic particles are synthesized. Both samples contain similar magnetite particles. Structural characterization of these particles is performed using x-ray diffraction, Fourier transform infrared spectra, dynamic light scattering, transmission electron microscopy and thermogravimetric analysis. Average crystallite size of magnetite is 7 nm. Thickness of oleic acid layer on each magnetite particle is 1 nm. The oleic acid coated sample contains 23% oleic acid. Temperature dependence of the zero field cooled and field cooled susceptibility of the uncoated magnetite particles peaks at 120 K and both the curves bifurcate at 195 K. The peak temperature and the bifurcation temperature of the system decrease due to the oleic acid coating. The inverse susceptibility does not vary linearly with temperature in high temperature region. Magnetization versus applied magnetic field data at 250 K are analyzed in three different ways to study the interparticle interaction and the particle size distribution effects on magnetization. We find that the both factors affect the magnetization process of ferrimagnetic nanoparticles.

Application of Response Surface Methodology to Design and Optimize Purification of Acetone or Aqueous Acetone Extracts of Hop Cones (Humulus lupulus L.) Using Superparamagnetic Iron Oxide Nanoparticles for Xanthohumol Isolation.

Iron oxide nanoparticles (IONPs) are an ideal sorbent for magnetic dispersion extraction due to their superparamagnetic properties and developed and active surface. This work aims to use IONPs, obtained by chemical co-precipitation, to purify 100% acetone and 50% acetone extracts from hop cones (Humulus lupulus L.) obtained by ultrasonic-assisted solvent extraction. The extracts were purified from bitter acids (i.e., humulones, lupulones) to isolate xanthohumol. The sorption conditions were optimized depending on the composition of the extraction mixture, specifically the mass of IONPs and the time needed to achieve effective sorption using response surface methodology (RSM). An analysis of variance (ANOVA) was performed to assess the adequacy of the developed model, and a good agreement was found between the experimental data and the proposed model. The polynomial equation describing the model is highly significant (p < 0.05), with a precision of Adeq (above 4). This indicates the usefulness of the polynomial regression model for prediction in experimental design. The final products of the purification for 100% acetone extracts and 50% acetone contain 40.58 ± 2.84 µg mL-1 and 57.64 ± 0.83 µg mL-1 of xanthohumol, respectively. The use of 50% acetone extract provides more favorable conditions due to the smaller amount of nanoparticles required for extract purification and a higher recovery of xanthohumol. The development of a reliable multivariate model allowed for the optimization of the extract purification process, resulting in high-purity xanthohumol from natural sources.

Water purification and biological efficacy of green synthesized Co/Zn-Doped α-Fe2O3 nanoparticles

In the present study, Co/Zn doped α-Fe2O3 (Hematite) nanoparticles (NPs) were synthesized using polyvinylpyrrolidone (PVP) and Azadirachta indica (AI) leaves aqueous extract. The analytical techniques including XRD, UV, SEM, EDX, VSM, Raman, and FTIR, we were able to identify and characterize the structural, morphological and magnetic attributes of the synthesized NPs. The findings demonstrated that the synthesized NPs exhibit homogeneous spherical shapes with particle sizes ranging from 8.64 to 15.32 nm. The NPs have rhombohedral crystal lattices, with crystallite sizes of 23.25 nm for chemically synthesized doped α-Fe2O3 NPs and 12.52 nm for those synthesized using green methods. The magnetic study has shown that the saturation magnetization (Ms) value of NPs, which ranges from 36 to 45 emu/g at ambient temperature, exhibits superparamagnetic properties (300 K). The treatment of industrial wastewater and its reuse for agricultural purposes are the subjects of the current study. Different concentrations of doped α-Fe2O3 NPs were used as photocatalysts to degrade dyes in a bioreactor under UV light in a heterogeneous mixture. The degradation rates achieved were 96.42 % for Congo Red (CR) and 98.36 % for Eosin Yellow (EY). DPPH assays were conducted to evaluate the antioxidant activity of the synthesized doped α-Fe2O3 NPs. The percentage inhibition of DPPH radicals ranged from 71.13 % to 90.35 %. Our findings indicate that AI leaf extract holds promise as a valuable resource for the development of bioactive compounds and environmentally friendly approaches to synthesizing green NPs. This is primarily attributed to the increased accessibility of bioactive components with potent antioxidant properties. The combination of these benefits provides opportunities for novel uses in environmental cleanup, biological applications, and energy conversion.

A sensitive Fe3O4@MnO2 nanocatalyst designed for visual determination of total antioxidant capacity in fruit juice

Fruit juice is kind of popular beverage food worldwidely, and its total antioxidant capacity (TAC) is generally considered as an important index for people’s rational diet, thus accurate evaluation of its TAC is essential for human health guidance. Herein, we constructed a sensitive Fe3O4@MnO2 nanocatalyst that was delicately cored with magnetite nanoparticles (Fe3O4 NPs) and encapsulated with manganese dioxide (MnO2) nanoshells for fast and accurate TAC colorimetric analysis in fruit juice. The data showed the fabricated Fe3O4@MnO2 nanocatalysts performed with remarkable oxidase mimetic activities and could catalyze oxidization of colorimetric substrate without additional H2O2, and the limit of detection (LOD) was about 0.39 μM for ascorbic acid (AA) evaluation. Applied in commercial fruit juice products, the fabricated Fe3O4@MnO2 nanocatalysts showed a reliable and visual assessment for the accurate TAC analysis. In addition, the fabricated Fe3O4@MnO2 nanocatalysts could be easily recycled due to their intrinsic superparamagnetic property. Together, an intellegent Fe3O4@MnO2 nanocatalyst was well developed for visual TAC analysis in fruit juice with convenient applications in future.

Effective remediation of mercury (II) from aqueous solutions using CS-MnFe2O4-CoS-MWCNTs: Box-Behnken design optimization and adsorption isotherm, kinetics, and thermodynamics evaluation.

Mercury (Hg) is a hazardous heavy metal, non-biodegradable and toxic, posing a serious threat to aquatic life and human health. Therefore, the removal of Hg ions from contaminated water using effective and eco-friendly adsorbents is necessary. In the present study, three magnetic chitosan-based organic-inorganic nanocomposites, such as CS-MnFe2O4, CS-MnFe2O4-CoS, and CS-MnFe2O4-CoS-MWCNTs, were designed and constructed to investigate their capacity for adsorbing Hg ions from aqueous solutions. The physicochemical properties of prepared composites were characterized by various analyses. The BET analyses indicated their high surface area and porous structure, and the N2 adsorption-desorption showed that the modification of CS in three stages by MnFe2O4 and crosslinking reaction, CoS preparation, and MWCNT incorporation resulted in increased N2 adsorption. The XRD confirms the synthesis of MnFe2O4 and CoS in the CS matrix and also the distinct peaks of MWCNTs. The CS-MnFe2O4-CoS-MWCNTs showed acceptable thermal stability with 45% char yields and superparamagnetic properties with magnetic saturation (Ms) of 16 emu g-1. The interactive impacts of independent variables (pH, contact time, and adsorbent dosage) on the removal percentage of Hg(II) onto three prepared adsorbents, as well as the process optimization, were assessed by the Box-Behnken design. The optimum conditions were identified, and the data from the analysis of variance showed that the three independent factors (pH, contact time, and adsorbent dosage) significantly influenced the adsorption of Hg(II). The adsorption isotherm and thermodynamics analysis investigation showed that at low concentrations of Hg(II), the adsorption process was both endothermic and spontaneous for the studied adsorbents.

Highly sensitive colorimetric and paper-based detection for sildenafil in functional food based on monodispersed spherical magnetic graphene composite nanozyme

BackgroundSildenafil (SIL) is regarded as an illegal adulterant in functional foods. Some functional foods doped with SIL have posed significant concern about their safety risks. However, the facile colorimetric detection of SIL is rarely investigated. ResultsHerein, we prepared a monodispersed spherical composite nanozyme (Fe3O4–NH2/GONRs), possessing excellent peroxidase-like (POD-like) and catalase-like (CAT-like) activities and strong superparamagnetic property. The enzyme-like activities of Fe3O4–NH2/GONRs can be selectively inhibited by SIL due to the synergistic effect of hydrogen bonds and π-π stacking between Fe3O4–NH2/GONRs and SIL. Leveraging this mechanism, a highly sensitive and selective colorimetric detection for SIL with a detection limit (LOD) of 0.26 ng/mL was developed. In addition, we prepared a three-dimensional paper-based analytical device (3D-PAD) for SIL colorimetric detection with naked-eyes and the semi-quantitative analysis with a LOD of 88 ng/mL. SignificanceThe proposed colorimetric and PAD detections demonstrated the advantages of low-cost, highly sensitive and selective, thus have promise application potential in the rapid detection of adulterated functional foods.

Synthesis of succinate derivatives using a magnetically separable Fe3O4@gly@Furfural@Co(NO3)2 nanocatalyst at room temperature

A simple, one-pot synthesis of nine 3-(4-oxo-4,5-dihydro-thiazole-2-yl sulfanyl) succinate derivatives has been achieved in moderate to good yields via a three-component reaction of dialkyl acetylenedicarboxylates, phosphites, and rhodanine at room temperature conditions and a magnetically-separable Fe3O4@gly@Furfural@Co(NO3)2 nanocatalyst. The size, surface charge, superparamagnetic properties, crystalline structure, and surface functional groups of nanoparticles were characterized and carried out utilizing several techniques such as X-ray diffraction analysis (XRD), Field emission scanning electron microscopy (FESEM), and Value stream mapping (VSM).

Magnetic activated carbon for the removal of methyl orange from water via adsorption and Fenton-like degradation

Water pollution caused by organic dyes is a critical environmental issue. Although activated carbon (AC) is commonly used for dye adsorption, its effectiveness is limited by challenges in separation and regeneration. To address these limitations, a convenient recyclable magnetic activated carbon (MAC) was fabricated via co-precipitation and calcination method, serving as adsorbent and catalyst for methyl orange (MO) removal through a Fenton-like degradation process. Characterization techniques, including XRD, FTIR, SEM and TEM, confirmed that Fe3O4 nanoparticles (10–20 nm) were uniformly dispersed on AC surface. The MAC maintaining a high surface area (997 m2/g) and pore volume (0.795 cm3/g) and exhibited superparamagnetic properties with a saturated magnetization of 5.52 emu/g, enabling effective separation from aqueous solutions by magnet. Batch adsorption studies revealed that MO adsorption onto MAC followed pseudo-second-order kinetic and Freundlich isotherm model, with a maximum adsorption capacity of 205 mg/g at 25 °C. Thermodynamic analysis showed that the adsorption process was spontaneous and endothermic. Simultaneous degradation of MO and in-situ regeneration of MAC were achieved via Fenton-like reaction using sodium persulfate (PS). Under a PS concentration of 9 mmol/L, the MO removal efficiency near 95% after 60 min, with a total organic carbon (TOC) reduction of 83.1%. The reaction of Fe3O4 and oxygen functional groups on AC surface with PS facilitated the generation of SO4•-, thereby enhancing catalytic degradation of MO. The degradation efficiency improved as the temperature increased from 25 °C to 45 °C. Cycle tests demonstrated that the MO removal efficiency of MAC remained above 90% after 5 cycles of regeneration. Overall, this study highlights the potential of MAC for efficient removal of organic dyes from water through the coupling of adsorption and Fenton-like degradation, providing a promising solution for addressing water pollution challenges.

Magnetite Nanoparticle Assemblies and Their Biological Applications: A Review.

Magnetite nanoparticles (Fe3O4 NPs) have garnered significant attention over the past twenty years, primarily due to their superparamagnetic properties. These properties allow the NPs to respond to external magnetic fields, making them particularly useful in various technological applications. One of the most fascinating aspects of Fe3O4 NPs is their ability to self-assemble into complex structures. Research over this period has focused heavily on how these nanoparticles can be organized into a variety of superstructures, classified by their dimensionality-namely one-dimensional (1D), two-dimensional (2D), and three-dimensional (3D) configurations. Despite a wealth of studies, the literature lacks a systematic review that synthesizes these findings. This review aims to fill that gap by providing a thorough overview of the recent progress made in the fabrication and organization of Fe3O4 NP assemblies via a bottom-up self-assembly approach. This methodology enables the controlled construction of assemblies at the nanoscale, which can lead to distinctive functionalities compared to their individual counterparts. Furthermore, the review explores the diverse applications stemming from these nanoparticle assemblies, particularly emphasizing their contributions to important areas such as imaging, drug delivery, and the diagnosis and treatment of cancer.

Magnetic casein/CaCO3/Fe3O4 microspheres stimulate osteogenic differentiation

The quality of life is significantly impacted by bone defects, which calls for the creation of optimum restorative materials with particular qualities. Current repair materials, such as metal alloys, polymer scaffolds, and bone cement, have a number of drawbacks, such as poor fracture toughness, non-degradability, and insufficient osteogenic ability. To address these challenges, we designed a novel magnetic casein/CaCO3/Fe3O4 microspheres (CCFM), combining biodegradability, osteoinductivity, osteoconductivity, and osteogenesis properties together. In vitro studies confirmed the outstanding biocompatibility and osteogenic differentiation effects on MC3T3-E1 cells of CCFM, highlighting their potential as a promising bone regeneration platform for clinical applications. As a novel bone repair material with superparamagnetic properties, CCFM not only possess good osteoinductivity, osteoconductivity, and osteogenesis properties but also can remain in the lesion location for a long time under an external magnetic field, representing a significant advancement in the field of bone tissue engineering and offering new possibilities for effective bone defect remediation and patient care.

Coconut shell waste-based ZnFe2O4/PANI/rGO nanohybrid composites as excellent radar-absorbing material

In this work, we developed ZnFe2O4/PANI/rGO nanocomposites based on coconut shell waste through in situ polymerization as excellent radar-absorbing material (RAM). This research mainly focused on adjusting the ZnFe2O4 content to obtain optimal absorption of radar waves, especially in the X-band. The results showed that the diffraction pattern of the ZnFe2O4/PANI/rGO nanocomposites showed multiple phases (crystalline and amorphous), which increased the ZnFe2O4 content and affected the increasing diffraction intensity. The functional group of the ZnFe2O4/PANI/rGO nanocomposites was identified with the presence of the M–O group originating from ZnFe2O4 at wavenumbers 517 and 419 cm−1 of Zn–O and Fe–O groups, respectively. Meanwhile, quinoid and benzenoid rings from PANI and CO from rGO were identified at wavenumbers 1580, 1504, and 1710 cm−1, respectively. The morphology of the ZnFe2O4/PANI/rGO nanocomposites showed PANI was distributed on the ZnFe2O4 nanoparticles, which were subsequently deposited on the rGO. The ZnFe2O4/PANI/rGO nanocomposites exhibited superparamagnetic properties, as confirmed by their coercivity values ranging from 9.2 to 124.4 Oe. Interestingly, the ZnFe2O4/PANI/rGO nanocomposites with the P3 sample showed optimal RAM performance with a minimum reflection loss value of −39.8 dB at 7.6-GHz frequency with an effective absorption bandwidth of 1.1 GHz.

Single-domain structure of Fe3O4 nanoparticles encapsulation by magnetic surfactant M(AOT)2 (M=Co, Ni)

Investigating the magnetic nanoparticle size and the effective magnetic interactions that form the magnetic domain can lead us to nanoparticles with targeted applications, such as targeted drug delivery and higher resolution MRI imaging. In this study magnetic susceptibility and coercive field properties, and the structure size range of single-domain magnetic capsules with high magnetization were obtained by structural analysis of volumetric DLS properties. In this regard, the role of exchange, anisotropy, and magnetostatic interaction was investigated in the structure of a magnetic capsule containing Fe3O4 nanoparticles (MCap-NPs). The stable capsules were synthesized in an emulsion solution with magnetic surfactants M(AOT)2 (M = Co, Ni). Vibrating Sample Magnetometer (VSM) and capsule relative volume (CRV) of Dynamic Light Scattering (DLS) were used to determine the magnetic properties of the single-domain (SD) structure. The produced emulsion samples were found to have superparamagnetic properties property with saturation magnetization in the range of 2–6 × 10−3emu/g for NiCap-NPs, and 5-13 × 10−3emu/g for CoCap-NPs. The results show that nanoparticles have the most significant effect on magnetization. The coercive field, the anisotropy energy values, and the SD of M(AOT)2 were determined using magnetic susceptibility distribution. The outcome results show that the surface of the magnetic capsule plays an essential role in forming a single-domain structure. It was also found that the saturation magnetization of the samples in the emulsion solution is proportional to the nanoparticle density and not to the mass of nanoparticles. All produced samples have distinct peaks in CRV versus capsule size, and each peak follows a log-normal distribution. For both samples, except for the samples with molar ratios ω of 23 (Co3 and Ni4 samples), the positions of the second and third relative volume peaks were constant at 269 ± 3 nm and 424±6 nm, respectively. The behavior of the CRV function normalized to the peak size showed a proportionality between the coercive field and the CRV.

Imparting of Nearly Superparamagnetic Properties to Cryogel Scaffolds With Mesoporous MNPs for Magneto-Sensitive Tissue Engineering Strategies.

This work reports the assembly of mesoporous iron oxide nanoparticles (meso-MNPs) with cryogel scaffolds composed of chitosan and gelatin. Meso-MNPs with a particle size ranging from 2 and 50 nm, a surface area of 140.52 m2 g-1, and a pore volume of 0.27 cm3 g-1 were synthesized on a porous SiO2 template in the presence of PEG 6000 followed by leaching of SiO2. Different ratios of meso-MNPs were successfully incorporated into chitosan:gelatin cryogels up to an amount equivalent to the entire amount of polymer. The morphological structure and physicochemical properties of the cryogels were directly affected by the amount of MNPs. VSM curves showed that all composite cryogels could be magnetized by applying a magnetic field. In the context of the safety of magnetic cryogel scaffolds for use in biomedicine, it is important to note that all values are below the exposure limit for static magnetic fields, and according to cytotoxicity data, scaffolds containing meso-MNPs showed nontoxicity with cell viability ranging from 150% to 275%. In addition, microbial analysis with gram-negative and gram-positive bacteria showed that the scaffolds exhibited activity against these bacteria.

Agarose-coated Fe3O4 magnetic nanoparticles (ACMNPs) as draw solute for enhance forward osmosis (FO) desalination

Drawing on the collective insights and findings of prior researchers in the field of draw solution (DS) exploration, we have synthesized agarose-coated Fe3O4 magnetic nanoparticles (ACMNPs) with precise control at each stage to achieve superparamagnetic properties. This allows them to be separated from the DS at the end of the forward osmosis (FO) desalination process using a magnet, thereby producing fresh water. Furthermore, coating the magnetic nanoparticles (MNPs) with agarose, a superhydrophilic polymer, increases their solubility in an agarose-shell/Fe3O4-core structure. This approach represents the culmination of our efforts and ensures alignment with our desired objectives. In the experimental phase, Fe3O4 MNPs and ACMNPs were compared at different concentrations as draw solutes in the FO desalination process. The results demonstrated the effect of the agarose coating on the hydrophilicity of the ACMNPs. Ultimately, the findings indicate that MNPs, when appropriately coated with agarose, can be used as effective draw solutes in FO systems.

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.

Study on the adsorption efficiency and mechanism of Sb(V) in aqueous solutions using enhanced surfactant-modified iron-calcium composite

The presence of Sb(V) in aqueous solutions poses a significant threat to the surrounding environment, and current treatment methods are inadequate. In this study, a magnetic surfactant (CTAB)-modified iron-calcium composite (CTAB-IC) was successfully synthesized using iron-calcium composite as the base material. This novel composite was used for the efficient removal of Sb(V) from textile wastewater solutions. Characterization analyses revealed that the CTAB-IC material exhibits a rich long-prismatic structure and superparamagnetic properties, classifying it as a soft magnetic material. Post-adsorption particle agglomerates were found to comprise Ca, S, and O. Sequential batch experiments demonstrated a maximum adsorption capacity of 54.05 mg/g, with adsorption kinetics data fitting the pseudo-second-order model. The intraparticle diffusion model indicated the presence of multiple diffusion steps during the adsorption process. Additionally, the adsorption of Sb(V) by CTAB-IC was identified as a heterogeneous surface adsorption process, best described by the Freundlich model. The primary adsorption mechanisms involved the formation of surface Ca-O-Sb complexes and inner-sphere Fe-O-Sb complexes, as well as amorphous surface precipitation and electrostatic adsorption. Notably, the treatment of textile wastewater often results in iron-calcium-rich sludge, which is challenging to manage and valorize. This study explored the potential for resource recycling by utilizing CTAB to harness the Fe elements in textile wastewater sludge, thereby promoting waste-to-resource conversion.