Pure Magnetite Research Articles

Effect of pure (ligand-free) nanoparticles of magnetite in sodium chloride matrix on hematological indicators, blood gases, electrolytes and serum iron

AbstractOne of the physical methods for obtaining magnetite nanoparticles (NPs) is electron beam physical vapor deposition (EB PVD), which requires complex equipment, but allows obtaining a significant amount of pure (ligand-free) NPs. The biomedical application of such NPs is less studied than materials from other synthesis methods. The objective is to study the effect of pure magnetite NPs in the NaCl matrix obtained by EB PVD on hematological indicators, gases, electrolytes and parameters of iron metabolism in the blood of intact animals. The physical characteristics of NPs were studied using high-resolution transmission electron microscopy, scanning transmission electron microscopy, energy-dispersive X-ray spectroscopy mapping, electron energy-loss spectroscopy, selected area electron diffraction and fast Fourier transform. In vivo experiments were conducted on albino male rats, which were injected with solution of magnetite-sodium chloride NPs (1.35 mg Fe/kg). After 3 and 72 h, hematological parameters, blood gases, electrolytes, and serum iron were determined. The synthesized NPs had an average size of 11 nm. They were identified as magnetite, where polycrystals and single crystals were present. The absence of contamination in crystal boundaries, clear orientation and orderliness of atoms in crystals were established. The administration of NPs in the sodium chloride matrix to animals was characterized by a transient increase in the main indicators of red blood accompanied by an increase in the saturation of erythrocytes with hemoglobin and their mean volume after 3 h. It did not worsen blood gases and pH, but decreased blood Na+ content after 72 h. The investigated NPs caused changes in the parameters of serum iron characteristic to iron preparations, which after 3 h were smaller compared to the reference iron drug, and after 72 h—similar to it. More intense rapid effects on hematological parameters at lower serum iron indicate greater activity of the studied pure magnetite NPs obtained by EB PVD syntesis compared to the reference iron preparation.

Exploring the Substitution of Fe(III) by Gd(III) in Nanomagnetite.

A promising superparamagnetic nanomagnetite dipped with Gd was synthesized for possible medical applications. Its size and morphology are independent of Gd content ranging from 1 to 5%. Gadolinium (III) replaced Fe(III) in the lattice. The sizes of Gd-doped nanoparticles ranged from 5 to 50 nm and exhibited a pure magnetite mineralogical phase.

Synthesis, characterization, and biocompatibility of pure and doped magnetite nanoparticles for magnetic hyperthermia in cancer treatment

Synthesis, characterization, and biocompatibility of pure and doped magnetite nanoparticles for magnetic hyperthermia in cancer treatment

Synthesis of Ag/CuS doped mineral magnetite nanocomposite with improved photocatalytic activity against tetracycline and diclofenac pollutants

The contamination of water sources by pharmaceutical pollutants presents significant environmental and health hazards, making the development of effective photocatalytic materials crucial for their removal. This research focuses on the synthesis of a novel Ag/CuS/Fe₃O₄ nanocomposite and its photocatalytic efficiency against tetracycline (TC) and diclofenac contaminants. The nanocomposite was created through a straightforward and scalable precipitation method, integrating silver nanoparticles (AgNPs) and copper sulfide (CuS) into a magnetite framework. Various analytical techniques, including X-ray diffraction (XRD), scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FTIR),ultraviolet–visible spectrophotometry (UV–Vis) and energy-dispersive X-ray spectroscopy (EDS), were employed to characterize the structural and morphological properties of the synthesized material. The photocatalytic activity was tested by degrading tetracycline and diclofenac under visible light. Results indicated a marked improvement in the photocatalytic performance of the Ag/CuS/Fe₃O₄ nanocomposite (98%photodegradation of TC 60 ppm in 30 min) compared to both pure magnetite and CuS/Fe₃O₄. The enhanced photocatalytic efficiency is attributed to the synergistic interaction between AgNPs, CuS, and Fe3O4, which improves light absorption and charge separation, thereby increasing the generation of reactive oxygen species (ROS) and promoting the degradation of the pollutants. The rate constant k of photodegradation was about 0.1 min−1 for catalyst dosages 0.02 g. Also the effect of photocatalyst dose and concentration of TC and pH of solution was tested. The modified photocatalyst was also used for simultaneous photodegradation of TC and diclofenac successfully. This study highlights the potential of the Ag/CuS/Fe₃O₄ nanocomposite as an efficient and reusable photocatalyst for eliminating pharmaceutical pollutants from water.

Impacts of designed vanillic acid-polymer-magnetic iron oxide nanocomposite on breast cancer cells

The engineered nano-vehicle was constructed using magnetic iron oxide nanoparticles (MIONs) and chitosan (CTS) to stabilize anticancer agent vanillic acid (VNA) which was loaded on CTS-coated MIONs nanocarrier, and more importantly, to achieve sustained VNA release and subsequent proper anticancer activity. The new thermally stable VNA-CTS- MIONs nanocomposite was spherical with a middle diameter of 6 nm and had a high drug loading of about 11.8 %. The MIONs and resulting nanocomposite were composed of pure magnetite and therefore, were superparamagnetic with saturation magnetizations of 53.3 and 45.7 emu.g−1, respectively. The release profiles of VNA from VNA-CTS-MIONs nanocomposite in different pH values were sustained and showed controlled pH-responsive delivery of the loaded VNA with 89 % and 74 % percentage release within 2354 and 4046 min at pH 5 and 7.4, respectively, as well as were in accordance with the pseudo-second-order model. The VNA-CTS-MIONs nanocomposite treatment at diverse concentrations remarkably decreased the viability and promoted ROS accumulation and apoptosis in the MDA-MB-231 breast cancer cells. Hence, it can be a propitious candidate for the management of breast cancer in the future.

Fabrication, characterization, spectroscopic, and magnetic properties of polyaniline/magnetite (PANi/Fe3O4) nanocomposites

In this research, pure polyaniline (PANi), pure magnetite (Fe3O4), and then PANi/ Fe3O4 nanocomposites were prepared and characterized. FT-IR spectra of the prepared samples indicate successful polymerization of PANi onto Fe3O4. PANi/Fe3O4 nanocomposites exhibit broad absorption bands at specific wavenumbers, indicating the presence of various functional groups. The observed blue shift in certain peaks suggests the interaction between nitrogen atoms and oxygen atoms on the magnetite surface through hydrogen bonding. The intensity and wavenumber of the Fe3O4 band decrease, indicating weakened Fe–O bonds. These findings demonstrate a strong interaction and combination between PANi and Fe3O4 in the nanocomposites. Fe3O4 nanoparticles exhibit a regular spherical shape with an average diameter of 16 nm. However, they also show non-uniform size distribution due to aggregation into larger secondary particles, likely driven by attractive forces. PANi/Fe3O4 core-shell nanocomposites demonstrate clear morphological changes, with Fe3O4 nanoparticles well spread and wrapped by the PANi shell. The electron diffraction technique confirms the crystalline structure of Fe3O4 nanoparticles, showing diffraction rings consistent with magnetite. The results confirm the potential of incorporating magnetic Fe3O4 nanoparticles to impart magnetic functionality in the resulting PANi-based nanocomposite materials. Magnetic saturation measurements displayed an enhancement in magnetization with increasing Fe3O4 nanoparticles. The change in magnetic behavior for doped samples provides a means of tuning the magnetization strength of the composites to meet the application requirement such as data storage and magnetic sensors.

Towards High-Performance Photo-Fenton Degradation of Organic Pollutants with Magnetite-Silver Composites: Synthesis, Catalytic Reactions and In Situ Insights.

In this study, Fe3O4/Ag magnetite-silver (MSx) nanocomposites were investigated as catalysts for advanced oxidation processes by coupling the plasmonic effect of silver nanoparticles and the ferromagnetism of iron oxide species. A surfactant-free co-precipitation synthesis method yielded pure Fe3O4 magnetite and four types of MSx nanocomposites. Their characterisation included structural, compositional, morphological and optical analyses, revealing Fe3O4 magnetite and Ag silver phases with particle sizes ranging from 15 to 40 nm, increasing with the silver content. The heterostructures with silver reduced magnetite particle aggregation, as confirmed by dynamic light scattering. The UV-Vis spectra showed that the Fe:Ag ratio strongly influenced the absorbance, with a strong absorption band around 400 nm due to the silver phase. The oxidation kinetics of organic pollutants, monitored by in situ luminescence measurements using rhodamine B as a model system, demonstrated the higher performance of the developed catalysts with increasing Ag content. The specific surface area measurements highlighted the importance of active sites in the synergistic catalytic activity of Fe3O4/Ag nanocomposites in the photo-Fenton reaction. Finally, the straightforward fabrication of diverse Fe3O4/Ag heterostructures combining magnetism and plasmonic effects opens up promising possibilities for heterogeneous catalysis and environmental remediation.

Ries magnetic mineralogy: Exploring impact and post‐impact evolution of crater magnetism

AbstractLarge‐scale impact events are some of the most catastrophic and instantaneous geological processes in nature, and leave in their wake conspicuous geological structures with characteristic magnetic anomalies. Despite magnetic anomalies in craters being well‐documented, their relationship with the magnetic mineral composition of the target and impactites is not always straightforward. Furthermore, the influence of impact shock and post‐impact events in the magnetism of natural craters remains elusive. In the Ries crater, Germany, the negative magnetic anomalies are attributed to a reverse polarity remanent magnetization in the impact‐melt bearing lithologies. We report new chemical, rock‐, and mineral‐magnetic data from the shocked basement and impactites, from surface samples, NR73 and SUBO‐18 boreholes, and explore how temperature and hydrothermalism may influence the magnetic mineralogy in the crater. We identified shocked, pure magnetite in the basement, and low‐cation substituted magnetite in the impactites as the main magnetic carriers. The shocked basement is demagnetized but remains largely unaltered by post‐impact hydrothermalism, while the impactites show weak magnetization and are extensively altered by neutral‐to‐reducing post‐impact hydrothermalism. We suggest that the magnetic mineralogy of the demagnetized uplifted basement may contribute significantly to the magnetic anomaly variation, in line with recent findings from the Chicxulub peak‐ring.

Enhancing anticorrosive performance of epoxy-based coatings using magnetite/graphene hybrids modified with ionic liquids

Hybrid materials based on magnetite (Fe3O4) and graphene nanoplatelets (GNP) were prepared by the in situ co-precipitation synthesis of Fe3O4 in the presence of GNP aqueous dispersion. Alkyl-phosphonium–based ionic liquids bearing bromide (IL102) and diethyl phosphate (IL169) as the counter-anions were used for the first time to improve the dispersion of GNP. The successful preparation of the hybrids and the final incorporation of the ILs in the hybrids were confirmed by thermogravimetric analysis (TGA) and Fourier transform infrared (FTIR) spectroscopy. The exfoliation of the GNP sheets and the incorporation of Fe3O4 particles on the GNP surface were confirmed by transmission electron microscopy. The effect of different hybrids on the corrosion resistance of the epoxy coatings was evaluated in saline medium using by electrochemical impedance spectroscopy (EIS). Hybrids prepared by the in situ synthesis of magnetite (Mag@GNP) promoted better corrosion resistance than pure magnetite or those hybrids introduced into the epoxy coatings by physical blends, due to better dispersion of the former fillers into the epoxy matrix. The best anti-corrosion response was achieved using 5 % of Mag@GNP 102 due to the better filler dispersion and higher amount of incorporated ionic liquid in the system, which can act as inhibition agent for the corrosion process.

Rapid Measurement of Magnetic Particle Concentrations in Wildland–Urban Interface Fire Ashes and Runoff Using Compact NMR

Wildfires are increasing in size, frequency, and intensity, releasing increased amounts of contaminants, including magnetic particles, into the surrounding environment. The aim of this paper is to develop a sensing method for the detection and quantification of magnetic particles (MPs) in fire ash and fire runoff using a compact Time-Domain Nuclear Magnetic Resonance (TD-NMR) system. The system is made up of custom NMR electronics with a compact and rugged permanent magnet array designed to enable future deployment as an in situ sensor. A signal-to-noise ratio of 25 dB was measured for a single scan, and sufficient data can be acquired in one minute. A linear relationship with an R <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sup> value of 0.9699 was established between transverse relaxation rates and MP concentrations in ash samples. This was validated by testing known dilutions of pure magnetite particles and showing that they fit within the same linear curve. The developed approach was then applied to detect MPs in surface water, where changes in the relaxation rates as high as 400% were observed before and after a wildfire event. MPs were removed from the surface water using a magnetic particle separator to confirm that observed changes were solely due to the presence of MPs. The compact NMR system can be used as a simple and rapid approach to track and quantify the concentrations of magnetic particles released from fire ashes and also from other sources such as discharges from coal ash and other combustion ashes.

Green synthesis of gaharu leaf extract-modified magnetite as an adsorbent for methyl orange textile dyes

Magnetite, a widely synthesized compound utilized as an adsorbent in various processes, exhibits reduced adsorption efficiency due to aggregation in aqueous solutions. Addressing this limitation, modification of magnetite is necessary to mitigate agglomeration and enhance adsorption capacity. Herein, we propose the utilization of gaharu leaf extract for magnetite modification, leveraging its abundance as a byproduct of essential oil production and rich secondary metabolite content, which serves as a stabilizing agent in synthesis processes. Magnetite (M) and gaharu leaf extract-modified magnetite (MEDG) were synthesized and evaluated as adsorbents for methyl orange (MO) textile dyes. Characterization via FTIR, PSA, SEM-EDX, XRD, and VSM revealed distinctive features of MEDG, including vibrational peaks corresponding to organic functional groups derived from the secondary metabolites present in the gaharu leaf extract. These functional groups actively participate in the adsorption process and prevent magnetite aggregation. MEDG exhibited a particle size of 4408.7 nm, compared to 4625 nm for M, with both exhibiting face-centered cubic (fcc) crystal structures. Additionally, MEDG demonstrated a crystallinity percentage of 92.49 % and saturation magnetization of 34.43 emu/g, attributed to the incorporation of gaharu leaf extract. Adsorption studies demonstrated that MEDG and gaharu leaf simplicia (SDG) achieved maximal adsorption of MO at pH 3 for 60 min and pH 4 for 70 min, respectively, with an adsorption efficiency of 95–99 % for a 5 ppm MO solution. The adsorption kinetics followed Ho’s pseudo-second-order model, and the isotherm conformed to Freundlich’s model. Furthermore, M and MEDG exhibited high reusability, with up to 5 cycles of reuse, while SDG demonstrated 3 cycles. However, the adsorption efficiency decreased to 87 % for MEDG and 85.19 % for SDG upon the fifth repetition. In conclusion, modification of magnetite with gaharu leaf extract enhances its adsorption capacity, offering economic advantages over pure magnetite due to increased surface area andactivesites.

CREATION AND PROPERTIES OF BIOCOMPOSITE NANOPARTICLES BASED ON FUCOIDAN AS CARRIERS OF FIBRINOLYTIC ENZYME

Magnetically guided biodegradable nanocomposites are a new class of functional materials that expand the possibilities of clinical therapy. The paper describes the chemistry of the formation of a nanobiocomposite material based on a natural polymer synthesized by electrostatic interaction of a polysaccharide and magnetite in an aqueous medium. The possibility of electrostatic immobilization of a model fibrinolytic enzyme was studied. An increase in the electrochemical potential of particles during immobilization of a fibrinolytic enzyme was established by the method of dynamic light scattering. The degree of enzyme inclusion was 9.95±0.05 mass%. The average particle size of the nanobiocomposite material after immobilization of the enzyme was 264.3 nm. The study of the magnetic properties showed the absence of residual magnetization, which makes it possible to exclude the possibility of magnetic aggregation when using the biocomposite in a biological application. The saturation magnetization of the formed material was 57.1 ± 2.3 kA/m, which is lower than that of pure magnetite sol (MS ∼ 73.8 ± 3.4 kA/m), but sufficient for manipulation under conditions of resistance to blood flow. The kinetics of the release of an enzyme preparation in a phosphate buffer from a nanocomposite carrier based on fucoidan was studied. To study the kinetics of enzyme release by mathematical modeling, zero and first order models, the Korsmeier-Peppas model, the Higuchi model, and the Baker-Lonsdale model were used. It has been established that the kinetics of fibrinolytic enzyme release is described with high accuracy (r2 = 0.98) by the Korsmeier–Peppas equation, where the process of release of the enzyme preparation is influenced by diffusion obeying Fick's law. It has been established that zero and first order models are applicable only to the initial (0-40 min, where r2 = 0.96) and final (80-320 min, r2 = 0.93) stage of release.

Photoelectrochemical, optical and magnetic properties of magnetite nanoparticles

AbstractMagnetite magnetic nanoparticles are prepared using olive leaf extract as a green reducing and stabilizing agents. After reaction the product is heated up to get rid of the organic compounds and get pure magnetite nanoparticles. Differential scanning calorimetry is used to study the phase transformation as a function of heating temperature. Scanning electron microscope and high resolution transmission electron microscope show spherical and crystallized nanoparticles with a size of 5 nm. X‐ray diffraction and Raman and x‐ray photoelectron spectroscopy indicate the formation of Magnetite phase with high cristallinity and purity. The synthesized Magnetite nanoparticles are semiconductors with gap energy around 2 eV. Observed by transmission electron microscope graphite rods with stacked carbon disks are decorated with the prepared nanoparticles and show enhanced photocurrent. The vibrating sample magnetometer measurements indicate that the prepared Magnetite nanoparticles have superparamagnetic behavior. These results are very promising for clinical and water splitting applications.

Insight into the function of waste cooking oil in the magnetite reduction process

Using waste cooking oil (WCO) as a green reductant in the pyrometallurgical field can relieve environmental pressure, and the corresponding mechanism involved in the WCO reduction process should be clarified. Based on the cracking characteristics of oil, the mechanism of WCO in the reduction process was investigated by using pure magnetite (Fe3O4) as the reduction object. The reaction system of WCO–Fe3O4 under two different contact modes was analyzed. The results indicated that 700 μL WCO was completely cracked at 1200 °C within 2 min, and 84.1% Fe3O4 was reduced during this process. This result suggested that the reductions mainly occurred after oil cracking. Furthermore, the reducibility of carbon produced by cracking was weaker than that of conventional fossil-based carbon. Thus, WCO mainly provides reductants (H2, CO, C, etc.) for the reduction system and is difficult to directly use in reduction.

The influence of pure (ligandless) magnetite nanoparticles functionalization on blood gases and electrolytes in acute blood loss

Objective was to compare the effect of functionalization of magnetite (Fe3O4) nanoparticles (NPs) with sodium chloride (NaCl), or its combination with ethylmethylhydroxypyrydine succinate (EMHPS) and polyvinylpyrrolidone (PVP) on blood gases and electrolytes in acute blood loss. Ligandless magnetite NPs were synthesized by the electron beam technology and functionalized by mentioned agents. Size of NPs in colloidal solutions Fe3O4@NaCl, Fe3O4@NaCl@EMHPS, Fe3O4@NaCl@PVP, Fe3O4@NaCl@EMHPS@PVP (nanosystems 1–4) was determined by dynamic light scattering. In vivo experiments were performed on 27 Wistar rats. Acute blood loss was modeled by removal 25 % circulating blood. Nanosystems 1–4 were administered to animals intaperitoneally after the blood loss with followed determination of blood gases, pH and electrolytes. In blood loss, nanosystems Fe3O4@NaCl and Fe3O4@NaCl@PVP were able to improve the state of blood gases, pH, and the ratio of sodium/potassium in the blood. So, magnetite NPs with a certain surface modification can promote oxygen transport under hypoxic conditions.

Specific absorption rate in quasispherical and elongated aggregates of magnetite nanoparticles: Experimental characterization and numerical simulation

Assemblies of magnetite nanoparticles created by the ultrasonic mechanocavitation in a viscous liquid have been obtained for use in magnetic hyperthermia. The magnetite nanoparticles inherit the perfect crystal structure of the original coarse-grained magnetite powder, with characteristic sizes of 0.2–8 μm, and have a high saturation magnetization, Ms = 92 emu/g, close to the value of pure magnetite. Measurements of the specific absorption rate (SAR) of assemblies in an alternating (ac) magnetic field showed a significant dependence of SAR on the nanoparticle concentration, as well as on the shape of particle macroaggregates. A 4-fold increase in the SAR of elongated clusters of particles oriented parallel to the action of ac magnetic field was found in comparison with an assembly of quasi-spherical clusters. In addition a sharp dependence of the SAR of an assembly of elongated clusters on the ac magnetic field direction with respect to the cluster orientation axis was revealed. The results obtained are in qualitative agreement with the results of numerical simulation of dense clusters of magnetic nanoparticles based on the solution of the stochastic Landau-Lifshitz equation.

A Simple Portable Magnetometer Based on Magnets and Hall-Effect Sensors Capable of Measuring Magnetic Properties

A magnetometer based on Hall effect sensors was developed using a 1020 steel base, two magnets (K&amp;J Magnetics, Pipersville, PA, USA), and two Hall effect sensors: MLX-90215 (Melexis Inc., San Jose, CA, USA) and AD-AD22151 (Analog Devices, Inc., Wilmington, MA, USA). Both sensors were assembled on an acrylic support and powered with a 5-volt battery. The readings can be taken using bench multimeters (HP 34401A or Iminipa ET-2042D). The magnetometer records magnetic hysteresis loop and saturation by applying a field of up to 0.33 T at room temperature. The device was tested using magnetic hysteresis data from samples of 99% pure nickel sphere and magnetite microparticles. A dipole magnetic model was used to obtain the moment of the samples. The sensor used for reading the induced magnetic field of the sample AD-AD22151 has a sensitivity can be adjusted from to 110 mV/mT. This device is cheap, versatile, and easy to build, and despite its low accuracy, when compared to commercial equipment, it can be useful in low-budget teaching and research laboratories.

Sorafenib tosylate loaded superparamagnetic nanoparticles: Development, optimization and cytotoxicity analysis on HepG2 human hepatocellular carcinoma cell line

Iron oxide (magnetite) is the core of magnetic nanoparticles, which can be directed to the desired location using an external magnet. In this study, the magnetic nanoparticles were prepared by an emulsion solvent evaporation method and optimized using Box Behnken design. The mean particle size, polydispersity index, and zeta potential of optimized nanoparticles (formulation PMP-11) were 71.81 ± 4.4 to 384.1 ± 10.5 nm, 0.203 ± 0.008 to 0.777 ± 0.010, and −34.4 ± 3.1 to −10.2 ± 0.6 mV, respectively. The entrapment efficiency was found to be 84.64 ± 0.78%. TEM image confirmed formation of spherical nanoparticles. After 24 h, the formulations released 25.18%–56.63% and 54.38%–90.56% of loaded drug in phosphate buffer (6.8 pH) and 0.1 N HCl (pH 1.2), respectively. In HepG2 cell lines, the IC50 value of optimized formulation was recorded to be 38.12 μg/mL. XRD analysis confirmed amorphous form of loaded drug. The mean average surface roughness for magnetite and optimized formulation was found to be 5.27025 nm and 8.29138 nm, respectively. The magnetization saturation for magnetite and optimized was 28.58 emu/g and 25.46 emu/g, respectively. Electron paramagnetic resonance spectroscopy of pure magnetite indicated g-Lande factor of 4.30 (typical for Fe3+ ions). The g factor for optimized formulation was 4.24 suggesting superparamagnetic nature of the particles.

Functionalization and Haemolytic analysis of pure superparamagnetic magnetite nanoparticle for hyperthermia application.

Superparamagnetic iron oxide nanoparticles (SPIONPs) are widely used in clinical research. The single domain nanoparticles are used in magnetic fluid hyperthermia (MFH) to treat cancer. When nanoparticles are exposed to an external magnetic field, it generates heat destroying tumour cells. SPIONPs have a large surface area, so the particles tend to aggregate, which leads to the destabilization of the colloidal system. To enhance the stability and biocompatibility of the nanomaterials, it is necessary to coat the surface with biocompatible material. Magnetite (Fe3O4) is a superparamagnetic nanoparticle (SPNPs) that was functionalized with oleic acid (OA) by sol-gel process using ethanol as the solvent. The oleic acid-coated magnetite (OA-Fe3O4) was characterized by X-ray powder diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), transmission electron microscopy (TEM), thermogravimetric analysis (TGA), UV-Visible diffuse reflectance spectroscopy (UV-DRS) and vibrating sample magnetometer (VSM). The haemolysis test has been used to investigate the haemocompatibility properties of nanomaterials. Hyperthermia study shows a high SAR value for the concentration of 1mg/ml at the field of 600 Oe and frequency of 316kHz. The OA coating enhanced the haemocompatibility of synthesized magnetite nanoparticles which can be used for magnetic fluid hyperthermia applications.

Carboxyl and thiol-functionalized magnetic nanoadsorbents for efficient and simultaneous removal of Pb(II), Cd(II), and Ni(II) heavy metal ions from aqueous solutions: Studies of adsorption, kinetics, and isotherms

Magnetic nanoparticles (MNPs) are important adsorbents for removing heavy metal ions (HMIs) from water due to their high surface area, abundant active adsorption sites after functionalization, magnetic separability, and reusability. However, compared with removing a single type of metal ion (single system), the simultaneous removal of multiple coexisting types of HMIs (e.g., ternary system) is challenging. To address this issue, in this study, Fe3O4 MNPs were functionalized with thiol (–SH) and carboxylic (–COOH) groups using meso-2,3-dimercaptosuccinic acid (DMSA). The MNP-DMSA nanoadsorbent was used for the simultaneous removal of Pb(II), Ni(II), and Cd(II) from aqueous solutions. The nanoadsorbent was extensively characterized and its adsorption behavior was investigated based on kinetic and isotherm studies using batch adsorption experiments. Highly monodispersed MNPs with the size of 8.24 ± 1 nm and the pure magnetite phase were synthesized using the thermal decomposition method. Fourier transform infrared spectroscopy and X-ray photoelectron spectroscopy analyses confirmed the successful modification of the surfaces of the MNPs by DMSA ligands. The MNP-DMSA nanoadsorbents exhibited good colloidal stability according to zeta potential measurements. The maximum adsorption capacities (qm) for the simultaneous removal of Pb(II), Ni(II), and Cd(II) in the ternary system were determined as 64.5, 53.9, and 27.18 mg/g, respectively. In single systems, the qm values for Pb(II), Ni(II), and Cd(II) were increased to 116.54, 102.73, and 75.48 mg/g, respectively. The adsorption kinetics and isotherm followed Langmuir and pseudo-second order models, respectively. An adsorption/desorption experiment demonstrated the reusability of the nanoadsorbent.