Size Of Fe3O4 Nanoparticles Research Articles

Investigation of the Application of Reduced Graphene Oxide-SPION Quantum Dots for Magnetic Hyperthermia.

Integrating hyperthermia with conventional cancer therapies shows promise in improving treatment efficacy while mitigating their side effects. Nanotechnology-based hyperthermia, particularly using superparamagnetic iron oxide nanoparticles (SPIONs), offers a simplified solution for cancer treatment. In this study, we developed composites of SPION quantum dots (Fe3O4) with reduced graphene oxide (Fe3O4/RGO) using the coprecipitation method and investigated their potential application in magnetic hyperthermia. The size of Fe3O4 nanoparticles was controlled within the quantum dot range (≤10 nm) by varying the synthesis parameters, including reaction time as well as the concentration of ammonia and graphene oxide, where their biocompatibility was further improved with the inclusion of polyethylene glycol (PEG). These nanocomposites exhibited low cytotoxic effects on healthy cells (CHO-K1) over an incubation period of 24 h, though the inclusion of PEG enhanced their biocompatibility for longer incubation periods over 48 h. The Fe3O4/RGO composites dispersed in acidic pH buffer (pH 4.66) exhibited considerable heating effects, with the solution temperature increasing by ~10 °C within 5 min of exposure to pulsed magnetic fields, as compared to their dispersions in phosphate buffer and aqueous dimethylsulfoxide solutions. These results demonstrated the feasibility of using quantum dot Fe3O4/RGO composites for magnetic hyperthermia-based therapy to treat cancer, with further studies required to systematically optimize their magnetic properties and evaluate their efficacy for in vitro and in vivo applications.

Impact of Iron Oxide on Anaerobic Digestion of Frass in Biogas and Methanogenic Archaeal Communities' Analysis.

With the increasing prominence of the global energy problem, socioeconomic activities have been seriously affected. Biofuels, as a renewable source of energy, are of great significance in promoting sustainable development. In this study, batch anaerobic digestion (AD) of frass (swine manure after bioconversion by black soldier fly larvae) and co-digestion with corn straw after the addition of iron oxide (Fe3O4) nanoparticles is investigated, as well as the start-up period without inoculation. The biochemical methane potential of pure frass was obtained using blank 1 group and after the addition of various sizes of Fe3O4 nanoparticles for 30 days period, and similarly, the digestion of frass with straw (blank 2) and after the addition of various sizes of Fe3O4 nanoparticles for 61 days period. The results showed that the average gas production was 209.43 mL/gVS, 197.68 mL/gVS, 151.85 mL/gVS, and 238.15 mL/gVS for the blank, ~176 nm, ~164 nm, and ~184 nm, respectively. The average gas production of frass with straw (blank 2) was 261.64 mL/gVS, 259.62 mL/gVS, 241.51 mL/gVS, and 285.98 mL/gVS for blank 2, ~176 nm, ~164 nm, and ~184 nm, respectively. Meanwhile, the accumulated methane production of the ~184 nm group was 2312.98 mL and 10,952.96 mL, respectively, which significantly increased the biogas production compared to the other groups. The methanogenic results of the frass (30 days) indicated that Methanocorpusculum, Methanosarcina, and Methanomassiliicoccus are the important methanogenic species in the AD reactor, while the microbial diversity of the ~184 nm group was optimal, which may be the reason for the high gas production of ~184 nm.

Influences of two sizes of nano-Fe3O4 on stereolithography 3D printing properties of gel photoresist for photothermal-responsive hydrogel

Nanocomposite hydrogels enable augmented properties, functions, and responsive behaviors. In the field of stereolithography 3D printing of the photothermal responsive nanocomposite hydrogel, the influence of the size of nano-Fe3O4 on 3D printing properties is significant due to the sedimentation, but the relevant research is rare. In this study, for the fabrication of photothermal responsive hybrid hydrogel, poly(N-isopropylacrylamide-acrylamide)/nano-Fe3O4 [P(NIPAM-AM)/nano-Fe3O4] gel photoresist was prepared and digital light processing (DLP)-based 3D printing as one of the popular stereolithography 3D printing technology was utilized. The influences of two sizes of Fe3O4 nanoparticles (10 and 50 nm) denoted as nano-Fe3O4(10) and nano-Fe3O4(50) on DLP 3D printing properties of the gel photoresist were investigated in detail. The results reveal that the gel photoresist with nano-Fe3O4(10) obtained long exposure time for the basic prototype, low overcuring degree (Od), and good uniformity of nanoparticles in hybrid hydrogels, while those with nano-Fe3O4(50) had the merits of printing high 3D sample due to the low release fore. Unfortunately, the gel photoresist with a high content of nano-Fe3O4 such as 3.11 wt% failed in 3D printing of a high and uniform gel cylinder. A strategy of preparing P(NIPAM-AM)/nano-Fe3O4 gel photoresist with mixed nano-Fe3O4(10) and (50) for 3D printing was proposed. Using the gel photoresist (nano-Fe3O4 content: 3.11 wt%) with two sizes of nano-Fe3O4 mixed with 50% each and the exposure time of 8 s, a gel cylinder with a height of 1 cm was successfully printed with uniform nano-Fe3O4 distribution and low Od values (≤ 1.17%). Further, a biomimetic hydrogel octopus was 3D printed by using the gel photoresist with mixed nano-Fe3O4 and thereafter a near-infrared-light-driven waving motion of octopus tentacle was achieved successfully.

Evaluation of Fe3O4 incorporated functionalized carbon nanotube self-standing buckypaper as electrodes for solid-state symmetric supercapacitor

Iron (II, III) oxide and carbonaceous materials drawn considerable attention in energy storage owing to their special features. In this study, simple reverse co-precipitation, acid functionalization and vacuum filtration methods adopted to synthesis Fe3O4 nanoparticles of size 11 nm and –COOH acid functionalized multi-wall carbon nanotubes (FMWCNT). And further used them to prepare and optimize Fe3O4 in FMWCNT as 15 wt% and 25 wt% self-standing buckypapers of around 30-μm thickness as electrodes for solid-state symmetric capacitor in the form of coin cell. The results show that 15 wt% and 25 wt% of Fe3O4-FMWCNT buckypapers hybrid nanostructures have Fe3O4 nanoparticles successfully incorporated in FMWCNT. The 25 wt% Fe3O4-FMWCNT electrodes with charge transfer resistance of 140 Ohm showed high areal specific capacitance (Cs) 78.5 mF/cm2 and retained 80 % of its Cs until 800 cycles even at high current density of 1 mA/cm2, scan rate of 100 mV/s whereas 15 wt% Fe3O4-FMWCNT showed low Cs of 47 mF/cm2 and retained 80 % of its Cs over 5000 cycles whereas only FMWCNT show Cs is 36 mF/cm2 with 54 Ohm. Finally, a solid-state symmetric supercapacitor coin cell with self-standing 25 wt% Fe3O4-FMWCNT buckypaper showed an excellent power density of 129.5 mW cm−3 and energy density of 3.6 mWh cm−3 is the innovation of the current work. This is mainly attributed to the combined effect of pseudocapacitive behavior from Fe3O4 by faradaic reaction with additional charge transfer resistance and electric double layer (EDLC) behavior from FMWCNTs by non-faradaic of electronic, ionic transport during charging-discharging. As-made solid-state symmetric supercapacitor appears as a high-performance storage device without extra support of current collectors for practical applications and for fabrication of planar capacitors.

Phenomic and transcriptomic analyses reveal the sequential synthesis of Fe3O4 nanoparticles in Acidithiobacillus ferrooxidans BYM.

Understanding the molecular mechanism of magnetite (Fe3O4) nanoparticle synthesis in Acidithiobacillus ferrooxidans BYM is particularly important for the commercial development of biogenic Fe3O4 nanoparticles. The phenomic parameters such as intracellular iron content and number and size of Fe3O4 nanoparticles were significantly affected by different treatment conditions, i.e., FeSO4·7H2O concentrations (0, 40, and 80 g/L), growth times (12, 36, and 50 h), and magnetic field intensities (0.05, 3.5, and 15 mT) (P < 0.01). Transcriptome analysis revealed that 2,164, 1,587, and 1,061 differentially expressed genes (DEGs) were accordingly detected, and 24 significant expression profiles were identified in A. ferrooxidans BYM under the three treatment conditions. The construction of gene regulatory networks for Fe3O4 nanoparticle synthesis indicated that DEGs mainly enrich ion transport, oxidation-reduction process, membrane structure, signal transduction, and quorum sensing. The four modules were found to be significantly associated with Fe3O4 nanoparticle phenomic parameters using a weighted gene co-expression network. Ten hub genes significantly correlated with Fe3O4 nanoparticle phenomic parameters (P < 0.01) were finally selected from 24 eigengenes related to iron metabolism screened from these models. On the basis of the previous research results and the present study findings, we provide a hypothetical molecular model for Fe3O4 nanoparticle synthesis mediated by these hub genes in A. ferrooxidans BYM comprising membrane formation, iron uptake and transport, iron redox, and crystal maturity. Our results will enable in-depth studies of Fe3O4 nanoparticle synthesis in non-magnetotactic magnetosome-producing bacteria. IMPORTANCE As the most important non-magnetotactic magnetosome-producing bacteria, Acidithiobacillus ferrooxidans only requires very mild conditions to produce Fe3O4 nanoparticles, thus conferring greater flexibility and potential application in biomagnetic nanoparticle production. However, the available information cannot explain the mechanism of Fe3O4 nanoparticle formation in A. ferrooxidans. In this study, we applied phenomic and transcriptomic analyses to reveal this mechanism. We found that different treatment condition factors notably affect the phenomic data of Fe3O4 nanoparticle in A. ferrooxidans. Using transcriptomic analyses, the gene network controlling/regulating Fe3O4 nanoparticle biogenesis in A. ferrooxidans was proposed, excavating the candidate hub genes for Fe3O4 nanoparticle formation in A. ferrooxidans. Based on this information, a sequential model for Fe3O4 nanoparticle synthesis in A. ferrooxidans was hypothesized. It lays the groundwork for further clarifying the feature of Fe3O4 nanoparticle synthesis.

Green Synthesis of Fe3O4 Nanoparticles Using Green Betel Leaf Extract for Methylene Blue Adsorption

Abstract The synthesis of Fe3O4 nanoparticles has become a matter of interest because it has properties and useful applications in various fields. Using plant extracts using the green synthesis method to manufacture Fe3O4 nanoparticles is considered an effective, efficient, and environmentally friendly approach because it does not contain harmful chemicals. This study uses the green synthesis method to synthesize Fe3O4 nanoparticles from green betel leaf extract. The UV-Vis Fe3O4 nanoparticles showed continuous absorption at wavelengths between 300 nm and 800 nm and obtained a band gap energy of 1.87 eV. XRD analysis confirmed the crystal size of Fe3O4 nanoparticles (≈ 6.93 nm). The FTIR results show that functional groups from the leaf extract play a role in forming Fe3O4 nanoparticles, as evidenced by the presence of two Fe-O absorption bands at wave numbers 567 cm-1 and 482 cm-1. The SEM results showed a needle-like particle shape, the HR-TEM analysis showed spherical and needle-like shapes and nanoparticles size (≈ 29.82 nm) and the EDS analysis showed that Fe and O elements indicated the dominant iron oxide content of Fe3O4 with levels of 73.35% and 20.88%, respectively. The magnetization curve shows that the green synthesized magnetite has ferromagnetic properties. The ferromagnetic properties of Fe3O4 were then applied as methylene blue adsorbent and observed using UV-Vis spectroscopy, the most effective absorption ability was at a contact time of 120 minutes with a color degradation percentage of 98.75%. Keywords: Green synthesis, Fe3O4, Green betel, Adsorption, Methylene blue

Application of Functionalized Fe3O4 Magnetic Nanoparticles Using CTAB and SDS for Oil Separation from Oil-in-Water Nanoemulsions.

Using magnetic nanoparticles (MNPs) for emulsified oil separation from wastewater is becoming increasingly widespread. This study aims to synthesize MNPs using amphiphilic coatings to stabilize the MNPs and prevent their agglomeration for efficiently breaking oil-in-water nanoemulsions. We coat two different sizes of Fe3O4 nanoparticles (15-20 and 50-100 nm) using cetyltrimethylammonium bromide (CTAB) and sodium dodecyl sulfate (SDS) with surfactant-to-MNP mass ratios of 0.4 and 0.8. We study the effect of various variables on the demulsification performance, including the MNP size and concentration, coating materials, and MNP loading. Based on the oil-water separation analysis, the smaller size MNPs (MNP-S) show a better demulsification performance than the larger ones (MNP-L ) for a 1000 ppm dodecane-in-water emulsion containing nanosized oil droplets (250-300 nm). For smaller MNPs (MNP-S) and at low dosage level of 0.5 g/L, functionalizing with surfactant-to-MNP mass ratio of 0.4, the functionalization increases the separation efficiency (SE) from 57.5% for bare MNP-S to 86.1% and 99.8 for the SDS and CTAB coatings, respectively. The highest SE for MNP-S@CTAB and the zeta potential measurements imply that electrostatic attraction between negatively charged oil droplets (-55.9 ± 2.44 mV) and positively charged MNP-S@CTAB (+35.8 ± 0.34 mV) is the major contributor to a high SE. Furthermore, the reusability tests for MNP-S@CTAB reveal that after 10 cycles, the amount of oil adsorption capacity decreases slightly, from 20 to 19 mg/g, indicating an excellent stability of synthesized nanoparticles. In conclusion, functionalized MNPs with tailored functional groups feature a high oil SE that could be effectively used for oil separation from emulsified oily wastewater streams.

Electrochemical Sensing of H2O2 by Employing a Flexible Fe3O4/Graphene/Carbon Cloth as Working Electrode

We report the synthesis of Fe3O4/graphene (Fe3O4/Gr) nanocomposite for highly selective and highly sensitive peroxide sensor application. The nanocomposites were produced by a modified co-precipitation method. Further, structural, chemical, and morphological characterization of the Fe3O4/Gr was investigated by standard characterization techniques, such as X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscope (TEM) and high-resolution TEM (HRTEM), Fourier transform infrared (FTIR), and X-ray photoelectron spectroscopy (XPS). The average crystal size of Fe3O4 nanoparticles was calculated as 14.5 nm. Moreover, nanocomposite (Fe3O4/Gr) was employed to fabricate the flexible electrode using polymeric carbon fiber cloth or carbon cloth (pCFC or CC) as support. The electrochemical performance of as-fabricated Fe3O4/Gr/CC was evaluated toward H2O2 with excellent electrocatalytic activity. It was found that Fe3O4/Gr/CC-based electrodes show a good linear range, high sensitivity, and a low detection limit for H2O2 detection. The linear range for the optimized sensor was found to be in the range of 10-110 μM and limit of detection was calculated as 4.79 μM with a sensitivity of 0.037 µA μM-1 cm-2. The cost-effective materials used in this work as compared to noble metals provide satisfactory results. As well as showing high stability, the proposed biosensor is also highly reproducible.

Comparative X-Ray Diffraction (XRD) Study on the Synthesis of Natural Based Magnetic Silica Nanoparticles

The aim of this study was to compare the synthesis process of magnetic silica nanoparticles (Fe-SNP) through the analysis of X-ray Diffraction (XRD) results. Fe3O4 magnetic nanopowders was synthesized by ultrasonic assisted co-precipitation and Fe-SNP was synthesized by direct mixing method of sodium silicate (Na2SiO3) and magnetite (Fe3O4) and the sol-gel method. Silica sludge was used as a silica source from Indonesia geothermal power plant waste. The synthesized of Fe-SNP is the functionalization of Fe3O4 with silica. Variations concentration of Na2SiO3 is used for the direct mixing method and variations of Fe3O4 form is used for the sol-gel method. Particles formed and particle size were characterized by XRD. The XRD results showed that there is no SiO2 phase in the sample synthesized by direct mixing method while two phases of SiO2 and Fe3O4 were found in the sample synthesized by sol-gel method. The size of the Fe3O4 nanoparticles calculated with Scherer’s formula and it obtained 19.9 nm, while the Fe3O4 nanoparticles with the addition of 20 mL and 6 mL Na2SiO3 concentrations were 6,53 nm and 10,23 nm. For the sol-gel method the size of Fe3O4 nanoparticles obtained was 11,03 using Fe3O4 powders and 9,86 using Fe3O4 solutions.

Size-controlled synthesis of Fe3O4 and Fe3O4@SiO2 nanoparticles and their superparamagnetic properties tailoring

Superparamagnetic properties and fine-tuning of colloidal Fe3O4 nanoparticles are important for their widespread biomedical applications. Herein, colloidal Fe3O4 nanoparticles (NPs) of different sizes (8–20 ​nm) were prepared, and their hydrophilization with SiO2 shell coating to be Fe3O4@SiO2 core-shell had been realized successively. The size of Fe3O4 NPs was controlled by different heating rates. Transmission electron microscope (TEM), powder X-ray diffractometry (XRD), and vibrating sample magnetometer (VSM) were performed to examine the morphology, crystallinity, and magnetic properties of the prepared Fe3O4 and Fe3O4@SiO2 core-shell NPs, respectively. In addition, high resolution transmission electron microscope (HRTEM) results suggested that Fe3O4 NPs had well crystallization. Enabled by such, their superparamagnetic properties can be fine-tuned accordingly and cater to their potential applications.

Effect and mechanism of paclitaxel loaded on magnetic Fe3O4@mSiO2-NH2-FA nanocomposites to MCF-7 cells

Magnetic Fe3O4 nanoparticles were prepared via a simple hydrothermal method and utilized to load paclitaxel. The average particle size of Fe3O4 nanoparticles was found to be 20.2 ± 3.0 nm, and the calculated saturation magnetization reached 129.38 emu/g, verifying superparamagnetism of nanomaterials. The specific surface area and pore volume were 84.756 m2/g and 0.265 cm3/g, respectively. Subsequently, Fe3O4@mSiO2 nanoparticles were successfully fabricated using the Fe3O4 nanoparticles as precursors with an average size of 27.81 nm. The relevant saturation magnetization, zeta potential, and specific surface area of Fe3O4@mSiO2-NH2-FA were respectively 76.3 emu/g, −14.1 mV, and 324.410 m2/g. The pore volume and average adsorption pore size were 0.369 cm3/g and 4.548 nm, respectively. Compared to free paclitaxel, the solubility and stability of nanoparticles loaded with paclitaxel were improved. The drug loading efficiency and drug load of the nanoformulation were 44.26 and 11.38%, respectively. The Fe3O4@mSiO2-NH2-FA nanocomposites were easy to construct with excellent active targeting performance, pH sensitivity, and sustained-release effect. The nanoformulation also showed good biocompatibility, where the cell viability remained at 73.8% when the concentration reached 1200 μg/mL. The nanoformulation induced cell death through apoptosis, as confirmed by AO/EB staining and flow cytometry. Western blotting results suggested that the nanoformulation could induce iron death by inhibiting Glutathione Peroxidase 4 (GPX4) activity or decreasing Ferritin Heavy Chain 1 (FTH1) expression. Subsequently, the expression of HIF-1α was upregulated owing to the accumulation of reactive oxygen species (ROS), thus affecting the expression of apoptosis-related proteins regulated by p53, inducing cell apoptosis.

Macrophage-Mediated Delivery of Fe3O4-Nanoparticles: A Generalized Strategy to Deliver Iron to Tumor Microenvironment.

Iron is used to alter macrophage phenotypes and induce tumor cell death. Iron oxide nanoparticles can induce macrophage polarization into the M1 phenotype, which inhibits tumor growth and can dissociate into iron ions in macrophages. In this study, we proposed to construct high expression of Ferroportin1 macrophages as carriers to deliver Fe3O4-nanoparticles and iron directly to tumor sites. Three sizes of Fe3O4-nanoparticles with gradient concentrations were used. The migration ability of iron-carrying macrophages was confirmed by an in vitro migration experiment and monocyte chemoattractant protein-1 detection. The release of iron from macrophages was confirmed by determining their levels in the cell culture supernatant, and we constructed a high expression of ferroportin strain of macrophage lines to increase intracellular iron efflux by increasing membrane transferrin expression. Fe3O4-NPs in Ana-1 cells were degraded in lysosomes, and the amount of iron released was correlated with the expression of ferroportin1. After Fe3O4-nanoparticles uptake by macrophages, not only polarized macrophages into M1 phenotype, but the nanoparticles also dissolved in the lysosome and iron were released out of the cell. FPN1 is the only known Fe transporter; we use a Lentiviral vector carrying the FPN1 gene transfected into macrophages, has successfully constructed Ana-1-FPN1 cells, and maintains high expression of FPN1. Ana-1-FPN1 cells increase intracellular iron release. Fe3O4-nanoparticles loaded with engineered Ana-1 macrophages can act as a "reservoir" of iron. Our study provides proof of strategy for Fe3O4-NPs target delivery to the tumor microenvironment. Moreover, increase of intracellular iron efflux by overexpression of FPN1, cell carriers can act as a reservoir for iron, providing the basis for targeted delivery of Fe3O4-NPs and iron ions in vivo.

Encapsulating ultrafine Fe3O4 nanoparticles into interconnected 3D multiporous carbon for superior Li-ion energy storage

Although Fe3O4 has low cost and high theoretical capacity, its low electrical conductivity and significant volume changes during the reaction process result in poor electrochemical performance, particularly cycling performance, which limit its application as anode materials. To overcome these limitations, this study created Fe3O4@3D cellular carbon composites (Fe3O4@3D cellular carbon: Fe3O4@3D-CC) by homogeneously embedding ultrafine Fe3O4 nanoparticles of size around 10 nm in a three-dimensional cellular carbon skeleton using a template-assisted method. The porous structure enables for large volumes of electrolyte to be stored and features a dual continuous transport channel for ions and electrons, which can considerably improve the conductivity of the Fe3O4. Furthermore, 3D cellular carbon locks Fe3O4 nanoparticles, allowing them to adapt to volume changes during charge-discharge process and preventing structural degradation. Due to the aforementioned structural properties, this material has a first discharge-specific capacity of 2534 mA h g−1 at a rate of 0.1 C and can still reach 1011 mA h g−1 after 400 cycles at a high rate of 2 C. This keeps the theoretical capacity at 109 % and distinctly enhances the electrochemical performance of Fe3O4, particularly the cycling performance.

Fe3O4 embedded κ-carrageenan/sodium alginate hydrogels for the removal of basic dyes

Here, we introduce κ-carrageenan and sodium alginate based hydrogel (CAG-NaAlg-cl-polyAA) and hydrogel nanocomposite (CAG-NaAlg-cl-polyAA/Fe3O4) through a free radical crosslinking method using acrylic acid/ N,N′- methylenebisacrylamide as a monomer/crosslinker system. The hydrogel is stimuli-responsive and its water absorption efficiency is enhanced through the optimization of synthesis parameters. The synthesized superabsorbents have been sequentially characterized through HR-TEM, powder XRD, FTIR, SEM-EDS, and XPS analysis. The average particle size of Fe3O4 nanoparticles stabilized through the CAG-NaAlg-cl-polyAA hydrogel matrix is 10.7 ± 2.5 nm. The CAG-NaAlg-cl-polyAA hydrogel exhibited > 95 % dye removal efficiency for the removal of basic dyes (auramine O, crystal violet and malachite green), whereas the % dye removal potential of CAG-NaAlg-cl-polyAA/Fe3O4 is enhanced upto 99 % after the incorporation of Fe3O4 nanoparticles. Langmuir adsorption is the most favorable adsorption isotherm with R2 = 0.992 (auramine O, AU), 0.989 (malachite green, MG), and 0.974 (crystal violet, CV). Kinetic studies indicate that the adsorption of AU, CV, and MG follows pseudo 2nd order kinetics. Moreover, the reusability of the fabricated samples upto five consecutive cycles further explores its potential for the separation of basic textile dyes from industrial wastewater.

Synthesis of Fe3O4 Nanoparticles with Different Shapes Through a Co-Precipitation Method and Their Application

Magnetic Fe3O4 nanoparticles (NPs) were successfully synthesized via co-precipitation method using ferric chloride and ferrous sulphate as the starting materials. The shape and the size of Fe3O4 NPs were controlled by using different types of additive including ammonium hydroxide and sodium hydroxide. The results revealed that by adding ammonium hydroxide, the particles attained a spherical shape with a uniform size. On the other hand, the shape of the particles turned from spherical to cubic using sodium hydroxide. The magnetic results showed that both samples attained hysteresis loop, which indicated that both samples have ferromagnetic behavior. In addition, Fe3O4 NPs with cubic shape showed higher adsorptive behaviour towards Congo red compared to spherical Fe3O4 NPs, which is attributed to the enhancement of their magnetic properties. The adsorption of Congo red onto cubic Fe3O4 NPs was best described by Langmuir isotherm model, while spherical Fe3O4 NPs followed Freundlich isotherm model.

Remediation of Heavy Metals in the Leachate of the Final Waste Processing Site Using Magnetite Nanoparticles

Nanoparticles are iron oxides that are used in various fields of life, one of which is to absorb heavy metals. In this study, magnetite (Fe3O4) nanoparticles were synthesized using the correspirate method and magnetite nanoparticle templates with PEG-6000. Synthesis of magnetite nanoparticles was carried out to obtain magnetite nanoparticles to be used to remediate heavy metals Cu, Ni and Mn in waste leachate. The susceptibility analysis of the leachate sample type showed that the type of magnetic material. The calculation results from the XRD diffractogram obtained that the crystal size of Fe3O4 nanoparticles is 56.35 nm. By varying the mass of 0.4 grams of Fe3O4, 0.8 grams of Fe3O4 and coating Fe3O4 using PEG 6000, it is known that the reduction in the concentration of heavy metal Cu is 7.71%, 23.09% and 42.31%, respectively. The percentage reduction in the concentration of heavy metal Ni was 6.29%, 9.45% and 7.09%, respectively.The percentage reduction in the concentration of heavy metal Mn was 25.369%, 19.98% and 4.05%, respectively. This indicates that Fe3O4 and PEG-6000 nanoparticles are able to reduce the concentration of heavy metals in waste leachate contained in the leachate sample

Remediation of Heavy Metals in the Leachate of the Final Waste Processing Site Using Magnetite Nanoparticles

Nanoparticles are iron oxides that are used in various fields of life, one of which is to absorb heavy metals. In this study, magnetite (Fe3O4) nanoparticles were synthesized using the correspirate method and magnetite nanoparticle templates with PEG-6000. Synthesis of magnetite nanoparticles was carried out to obtain magnetite nanoparticles to be used to remediate heavy metals Cu, Ni and Mn in waste leachate. The susceptibility analysis of the leachate sample type showed that the type of magnetic material. The calculation results from the XRD diffractogram obtained that the crystal size of Fe3O4 nanoparticles is 56.35 nm. By varying the mass of 0.4 grams of Fe3O4, 0.8 grams of Fe3O4 and coating Fe3O4 using PEG 6000, it is known that the reduction in the concentration of heavy metal Cu is 7.71%, 23.09% and 42.31%, respectively. The percentage reduction in the concentration of heavy metal Ni was 6.29%, 9.45% and 7.09%, respectively.The percentage reduction in the concentration of heavy metal Mn was 25.369%, 19.98% and 4.05%, respectively. This indicates that Fe3O4 and PEG-6000 nanoparticles are able to reduce the concentration of heavy metals in waste leachate contained in the leachate sample

Toxicological effects of the mixed iron oxide nanoparticle (Fe3O4 NP) on murine fibroblasts LA-9

ABSTRACT The increase in large-scale production of magnetic nanoparticles (NP) associated with the incomplete comprehensive knowledge regarding the potential risks of their use on environmental and human health makes it necessary to study the biological effects of these particles on organisms at the cellular level. The aim of this study to examine the cellular effects on fibroblast lineage LA-9 after exposure to mixed iron oxide NP (Fe3O4 NP). The following analyses were performed: field emission gun–scanning electron microscopy (SEM-FEG), dynamic light scattering (DLS), zeta potential, ultraviolet/visible region spectroscopy (UV/VIS), and attenuated total reactance-Fourier transform infrared (ATR-FTIR) spectroscopy analyses for characterization of the NP. The assays included cell viability, morphology, clonogenic potential, oxidative stress as measurement of reactive oxygen species (ROS) and nitric oxide (NO) levels, cytokines quantification interleukin 6 (IL-6) and tumor necrosis factor (TNF), NP uptake, and cell death. The size of Fe3O4 NP was 26.3 nm when evaluated in water through DLS. Fe3O4 NP did not reduce fibroblast cell viability until the highest concentration tested (250 µg/ml), which showed a decrease in clonogenic potential as well as small morphological changes after exposure for 48 and 72 hr. The NP concentration of 250 µg/ml induced enhanced ROS and NO production after 24 hr treatment. The uptake assay exhibited time-dependent Fe3O4 NP internalization at all concentrations tested with no significant cell death. Hence, exposure of fibroblasts to Fe3O4 NP-induced oxidative stress but not reduced cell viability or death. However, the decrease in the clonogenic potential at the highest concentration demonstrates cytotoxic effects attributed to Fe3O4 NP which occurred on the 7th day after exposure.

Synthesis of heterogeneous photo-Fenton catalyst from iron rust and its application to degradation of Acid Red 97 in aqueous medium

In this work, magnetic nanoparticles were synthesized from iron rust waste and used as a catalyst for photo-Fenton degradation of Acid red 97 (AR97). The morphology and size of Fe3O4 nanoparticles could be controlled by adding an appropriate amount of water as co-solvent in solvothermal treatment. For a comparative study, α-FeOOH and α-Fe2O3 with nanorod shape were also prepared from iron rust and employed as photo-Fenton catalyst. The photo-Fenton degradation results showed that the prepared Fe3O4 nanoparticles with spherical-like shape possessed higher catalytic activity than octahedral-shaped Fe3O4, α-FeOOH, and α-Fe2O3. It was demonstrated that the synergetic effect between H2O2 and oxalic acid (OA) led to an improvement in the catalytic efficiency of the photo-Fenton system towards AR97 degradation in awide pH range. At 180 min, about 81% of total organic carbon (TOC) was removed. Thus, the mineralization of organic matter is strongly involved during the photo-Fenton process. The quenching experiments showed that •OH radical played a crucial role in the degradation of AR97 by Fe3O4/H2O2/OA/UV system. Benefiting from the high catalytic activity and easy magnetic separation, the prepared Fe3O4 nanoparticles revealed good stability and reusability even after five consecutive cycles. This work offers a sustainable and effective way to recycle iron rust waste into an efficient catalyst for the degradation of organic contaminants in water.

Fabrication of selective gas sensors using Fe3O4 nanoparticles decorated with CuO

Metal-oxide nanoparticles are regarded as favorable candidates for different device applications including gas sensors. Decoration of nanoparticles with smaller ones of different types enables taking advantage of the physical and chemical characteristics of both core and decorate nanoparticles. Fe3O4 nanoparticles decorated with CuO are produced in this work by a coprecipitation method and investigated for their application for H2S gas sensor devices. The average size of Fe3O4 nanoparticles is 33.33∓5.55nm while the average grain size of the CuO nanoparticles is 9.72∓1.39nm. Gas sensors are fabricated by depositing dispersed nanoparticles on substrates with pre-printed interdigitated electrodes. Impedance spectroscopy is utilized to investigate the electrical characteristics of fabricated devices, where their activation energy is evaluated to 0.386±0.076eV. The fabricated sensors are found to be selective to H2S and sensitive to low concentrations, as low as 1.0 ppm, with minimum response time of 1.0 min. The produced sensors indicate potential for field applications due to their various features that include simplified and practical fabrication procedure, low power needs, high sensitivity, reasonable response time, and magnetic properties of nanoparticles that facilitate their recycling.