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The current difficulty in treating blood lead poisoning lies in effectively removing Pb-(II), which is mainly located inside red blood cells (>95%) and is complexed with hemoglobin, without causing damage to the blood environment. In this work, a new type of blood nanoremover that can safely enter red blood cells to remove the Pb-(II) located in the cells is reported. Specifically, using tetraethyl orthosilicate (TEOS) as the silicon source, a silica shell with a mesoporous pore size of about 30 nm was synthesized on the outer surface of Fe3O4 nanoparticles, resulting in Fe3O4/mSi with flower morphology. Then, dimercaptosuccinic acid (DMSA) with good affinity to Pb-(II) was modified inside the pores of the silica shell to obtain Fe3O4/mSi/D. The experimental results showed that the size of the synthesized Fe3O4/mSi/D was relatively uniform, and the pore structures were regular. Fe3O4/mSi/D would not cause obvious hemolysis and coagulation in the blood, and they could avoid the phagocytosis of the immune system and enter the red blood cells. The removal efficiency of Pb-(II) by Fe3O4/mSi/D can reach about 73.5% in 30 min. This strategy provides the possibility for the removal of heavy metals in blood. [ABSTRACT FROM AUTHOR]

Objective(s): Auraptene (AUR) is a monoterpene coumarin compound with several biological activities specifically anti-cancer. The bioavailability of AUR in biological fluids is negligible, thus, the cytotoxicity of this compound for the target cells is low. Herein, the synthesis of AUR-coated Fe3O4 nanoparticles is presented as a strategy to increase the cytotoxicity of AUR on PC3, DU145, and LNCaP prostate cancer cells. Materials and Methods: Fe3O4 nanoparticles were synthesized via co-precipitation method, coated with AUR and stabilized by dextran. They were characterized by X-ray diffraction spectroscopy (XRD), Fouriertransform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), dynamic light scattering (DLS) analysis, and vibrating sample magnetometry (VSM). In vitro release test for coated nanoparticles was performed in both physiologic (pH= 7.4) and acidic (pH= 5.5) environments. Cytotoxicity for prostate cancer cells was evaluated by AlamarBlue assay and the results were analyzed by one-way and two-way ANOVA tests. Results: Characterization outcomes represented the formation of magnetic nanoparticles with good crystalline structure, relatively spherical shape and superparamagnetic properties. AUR release profile from nanoparticles demonstrated that coated nanoparticles are able to inhibit burst release of this compound. AUR release was remarkably higher in acidic medium that can be advantageous for treating tumor regions. Cytotoxicity results indicated that AUR had a very low toxicity against prostate cancer cells at the tested concentrations. In contrast, AUR-coated Fe3O4 nanoparticles were significantly cytotoxic on all the cell lines. Conclusion: The coating of AUR on the surface of Fe3O4 nanoparticles was a successful approach to enhance the efficacy and cytotoxicity of this compound. [ABSTRACT FROM AUTHOR]

A novel molecularly imprinted electrochemical sensor based on ferric oxide nanoparticles modified glassy carbon electrode (GCE) was fabricated for detection of human growth hormone (HGH). The stable proteins molecularly imprinted polymer (MIP) films were made by electro-polymerization using aniline as functional monomer and HGH as the template. Electropolymerization was done in a range of − 0.3 to + 0.9 V at a scan rate of 0.1 V s−1 for 15 cycles. The accuracy of MIP/Fe3O4/GCE formation was confirmed using the square wave voltammetry technique from − 0.2 to + 0.6 V, in 5 mM solution of [Fe(CN)6]3−/4− with 0.1 M KCl. According to the results, the sensor showed a linear range from 1.0 × 10−10 to 1.0 × 10−7 g/cm3 of HGH (R2 = 0.9588) under optimal conditions with a detection limit of 0.6 × 10−10 g/cm3. The calibration curve showed a 95.8% correlation of the data. The human plasma sample analysis confirmed the applicability of the MIP/Fe3O4/GCE sensor to the assay of the HGH molecules. In conclusion, the sensor has sensitivity, high stability, and good repeatability. [ABSTRACT FROM AUTHOR]

Carbohydrate polymers were widely used in pharmaceuticals and drug delivery systems due to their biodegradability and biocompatibility. Among them, chitosan (Cs) has been considered in many new drug delivery systems. Poly(ethylene glycol) as a hydrophilic polymer can increase the solubility and stealth functions of nanocarriers. The Fe3O4 nanoparticles functionalized with polymers act as non-toxic drug vehicles for tumor targeting under external magnetic fields. In present study, the Fe3O4/SiO2-NH2 nanoparticles were prepared and then functionalized with methoxy-PEGylated chitosan (Cs-g-mPEG2000) and the hydroxyurea (HU) was loaded on this nanoparticles. The structure, crystallinity, and morphology of HU/Fe3O4/SiO2/Cs-g-mPEG2000 were determined using spectroscopic and electron microscopy analysis. Encapsulation efficiency of HU and the percentage of loading and release rate at different pH values at 37 °C were examined. Maximum drug release was observed at pH = 7.4. According to TEM results, the nanoparticle sizes were between 18 and 157 nm. The cytotoxicity effect of HU-loaded nanoparticles against MCF-7 human breast cancer cell was evaluated using MTT assay and cell cycle arrest analysis. The inhibitory concentration (IC50) values were 249 and 85 μg/mL on the MCF-7 cell line compared to the control group in 24 h and 96 h, respectively. In addition, the expression of p53 and lincRNA-P21 genes in treated cells and control group was assessed using real-time PCR, and the results showed that the ratio of p53 expression to lincRNA-P21 in MCF-7 cells was significantly increased (P < 0.05). The cell cycle arrested in the S-phase and the population of cells increased 1.3-fold compared to the control group. [ABSTRACT FROM AUTHOR]

At present, high-sensitivity, high-penetration-depth, and accurate tissue resolution clinical imaging effect are required, while computer transverse scanning, microwave imaging, and fluorescence imaging (FL) cannot meet the requirements of clinical imaging, but the magnetic resonance imaging (MRI) can meet the requirements of clinical dissecting details. The effect of MRI imaging is closely related to the contrast agent (CA). As an important type of CA, Fe3O4 and its analogues have been widely concerned because of their low toxicity and relatively low price. In this review, we summarize the development and improvement of CAs based on Fe3O4 and its analogues from T 2 imaging mode and development limitation in the initial single modulus imaging mode, to T 1 imaging mode overcoming the limitations of T 2 imaging and the limitations of its own in application, to the later development of dual modulus imaging form, and to the current multi-modulus imaging form. Simultaneously, we demonstrate the research progress, preparation methods, and future trends based on Fe3O4 and its analogues CAs for MRI, the current application status is preliminarily summarized, and the future development trend is prospected.

Fe3O4@SiO2-L-proline nanoparticles have been used as an effective catalyst for the preparation of pyrimidines by three-component reactions of 1,3-dimethylbarbituric acid, aromatic aldehydes and 4-methyl aniline or 4-methoxy aniline under reflux condition in ethanol. Fe3O4@SiO2-L-proline nanoparticles have been characterized by scanning electronic microscopy (SEM), powder X-ray diffraction (XRD), vibrating sample magnetometer (VSM), thermal gravimetric analysis (TGA), energy dispersive X-ray (EDS), dynamic light scattering (DLS) and FT-IR spectroscopy. This method provides several advantages including, the reusability of the catalyst, low catalyst loading, atom economy, short reaction times and high yields of products.

Background: In the past few years, Magnetite (Fe3O4) nanoparticles have gained a significant research interest in the field of biology, chemistry, metallurgy due to their wide range of applications. Some of their important applications include drug delivery, chemotherapy, low-friction seals, magnetic fluid, adsorbent, recovery of hazardous wastes, etc. Methods: In the present paper, we reported an eco-friendly route of preparing magnetite nanoparticles by using leaves of Tilia Tomentosa (Ihlamur) followed by calcination at 400 ˚C for 15 minutes. Results: The bandgap energy of the prepared Fe3O4 nanoparticles was studied by UV–Visible spectroscopy and the value was found to be 3.31 eV. The scanning electron microscopy (SEM) image showed the spherical magnetite nanoparticles with an average size of 25 nm. The phases and thermal properties of Fe3O4 nanoparticles were studied by using X-ray diffraction, thermogravimetric (TG) and differential thermal analysis (DTA). The enthalpy change of Fe3O4 nanoparticles was calculated by using the DTA curve and the value was found to be 4.97 kJ/mol at 8˚C/min heating rate. The antimicrobial activity of Fe3O4 nanoparticles was carried out by the minimum inhibition concentration (MIC) assay method. Except for B. subtilis, Fe3O4 nanoparticles demonstrated significant antibacterial property.Conclusion: The prepared magnetite nanoparticles showed excellent thermal stability and less weight loss over a 30–1000 ˚C temperature range. The size of the prepared magnetite nanoparticles is very less therefore they interacted effectively with the organelle, enzymes, and cells of bacteria and inhibited bacterial growth by killing them.

This study provides new information directed to solving the objective of highlighting and assessing the degree of hazard of nanoparticles to the environment. The proposed procedure is to apply as a model in the practice of monitoring the toxicity of metal oxide nanoparticles of pigmented yeasts. The proposed procedure is to apply, as a model, the nanoparticles of pigmented yeast Rhodosporidium toruloides (synonymous Rhodotorula gracilis) CNMN-Y-30 in the practice of monitoring the toxicity of metal oxide. Based on the response of the yeast, the level of toxicity of nanoparticles is determined based on the concentrations decrease by 50 % of the content of β-carotene in the biomass of yeasts and catalase antioxidant enzyme activity. This information can be used by professionals in the food industry, microbiology, medicine, cosmetology, textiles, etc., where those nanomaterials have applications.

Phenolic mediated nanoparticles (NPs) synthesis has gained a great attention as ecofriendly and sustainable approach in a wide range of nano functional materials. Magnetic iron oxide, (Fe3O4) NPs are increasingly studied for various biological applications. In this work, different wt% of Usnea Longissimma (U.L) methanol extract as green stabilizers were used to produce (U.L/Fe3O4) NPs followed by various characterization experiments and their antioxidant evaluation against 2, 2-diphenyl-1-picryl-hydrazyl, (DPPH), respectively. The results showed that the synthesized U.L/Fe3O4 NPs with their excellent antioxidant activities were high degree of crystallinity and purity. It is demonstrated from characterization study that the NPs had average size less than 10 nm. The U.L/Fe3O4 NPs morphological study showed that NPs are porous, well dispersed and mostly in an un-agglomerated form. It has been confirmed from the results that the synthesized NPs at 1–5 wt% U.L extract addition compared to trolox as a positive control gives the maximum antioxidant activity, with IC50 value of 300–800 μg/mL. It has been confirmed that U.L/Fe3O4 NPs are quite smaller in size and are efficient to show antioxidant activity which could be suggested for their possible biological applications.

Light-responsive hydrogel actuators show attractive biomedical applications for in vivo drug delivery tool, surgical tissue repair operation, and vascular cleaning due to its non-contact, rapid, precise, and remote spatial control of light. Conventional visible–light–responsive hydrogels contain special chemical structure or groups, and the difficulty in synthesis results in that few can be applied to fabricate visible–light–driven hydrogel actuators. In this study, based on photothermal effect, surface-modified Fe3O4 nanoparticles were incorporated into poly(N-isopropylacrylamide-acrylamide) hydrogel by UV photopolymerization, which revealed excellent green–light–responsive volume change. Under a laser irradiation of 200 mW at 520 nm, the bending angle deformation of hydrogel strips with 2.62 wt% Fe3O4 reached 107.8°. Strip-shaped hydrogel actuators could be applied to transport tiny objects. Furthermore, a boomerang-like hydrogel actuator was designed and fabricated to drive floating foam on water. By 12 cycles of continuous laser on–off irradiation to a hydrogel actuator underwater, a circular returning movement of the float was accomplished. The study on driving a float using visible–light–triggered hydrogel actuators provides a new idea for the design of light-driven biomedical devices and soft robots.

This work reports the use of mesoporous silica rods as templates for the step-wise preparation of multifunctional Fe3O4 NPs filled polydopamine hollow rods (Fe3O4@PDA HR). The capacity of as-synthesized Fe3O4@PDA HR as a new drug carrier platform was assessed by its loading and the triggered release of fosfomycin under various stimulations. It was found that the release of fosfomycin was pH dependent with ~89% of fosfomycin being released in pH 5 after 24 h, which was 2-fold higher than that in pH 7. The magnetic properties of Fe3O4 NPs and the photothermal properties of PDA enabled the triggered release of fosfomycin upon the exposure to rotational magnetic field, or NIR laser irradiation. Additionally, the capability of using multifunctional Fe3O4@PDA HR to eliminate preformed bacterial biofilm was demonstrated. Upon exposure to the rotational magnetic field, the biomass of a preformed biofilm was significantly reduced by 65.3% after a 20 min treatment with Fe3O4@PDA HR. Again, due to the excellent photothermal properties of PDA, a dramatic biomass decline (72.5%) was achieved after 10 min of laser exposure. This study offers an alternative approach of using drug carrier platform as a physical mean to kill pathogenic bacteria along with its traditional use for drug delivery.

Microwave absorption in radar stealth technology is faced with challenges in terms of its effectiveness in low-frequency regions. Herein, we report a new laser-based method for producing an ultrawideband metamaterial-based microwave absorber with a highly uniform sheet resistance and negative magnetic permeability at resonant frequencies, which results in a wide bandwidth in the L- to S-band. Control of the electrical sheet resistance uniformity has been achieved with less than 5% deviation at 400 Ω sq ^−1 and 6% deviation at 120 Ω sq ^−1 , resulting in a microwave absorption coefficient between 97.2% and 97.7% within a 1.56–18.3 GHz bandwidth for incident angles of 0°–40°, and there is no need for providing energy or an electrical power source during the operation. Porous N- and S-doped turbostratic graphene 2D patterns with embedded magnetic nanoparticles were produced simultaneously on a polyethylene terephthalate substrate via laser direct writing. The proposed low-frequency, wideband, wide-incident-angle, and high-electromagnetic-absorption microwave absorber can potentially be used in aviation, electromagnetic interference (EMI) suppression, and 5G applications.

(1) Background: Colon cancer is one of the most common cancer types, and treatment options, unfortunately, do not continually improve the survival rate of patients. With the unprecedented development of nanotechnologies, nanomedicine has become a significant direction in cancer research. Indeed, chemotherapeutics with nanoparticles (NPs) in cancer treatment is an outstanding new treatment principle. (2) Methods: Fe3O4 NPs were synthesized and characterized. Caco-2 colon cancer cells were treated during two different periods (24 and 72 h) with Fe3O4 NPs (6 μg/mL), various concentrations of 5-FU (4–16 μg/mL), and Fe3O4 NPs in combination with 5-FU (4–16 μg/mL) (Fe3O4 NPs + 5-FU). (3) Results: The MTT assay showed that treating the cells with Fe3O4 NPs + 5-FU at 16 µg/mL for 24 or 72 h decreased cell viability and increased their LDH release (p < 0.05 and p < 0.01, respectively). Furthermore, at the same treatment concentrations, total antioxidant capacity (TAC) was decreased (p < 0.05 and p < 0.01, respectively), and total oxidant status (TOS) increased (p < 0.05 and p < 0.01, respectively). Moreover, after treatment with Fe3O4-NPs + 5-FU, the IL-10 gene was downregulated and PTEN gene expression was upregulated (p < 0.05 and p < 0.01, respectively) compared with those of the control. (4) Conclusions: Fe3O4 NPs exert a synergistic cytotoxic effect with 5-FU on Caco-2 cells at concentrations below the active drug threshold levels.

Magnetite (Fe 3 O 4 ) particles have been widely reported to enhance the anammox's activity in anammox granular sludge (AnGS), yet the underlying mechanisms remain unclear. This study demonstrates that both Fe 3 O 4 microparticles (MPs) and nanoparticles (NPs) at a dosage of 200 mg Fe 3 O 4 /L significantly increased the specific anammox activity (SAA) of AnGS. Additionally, the transcriptional activities of the hzs and hdh genes involved in the anammox process, as well as the heme c content in AnGS, were also notably enhanced. Notably, Fe 3 O 4 NPs were more effective than MPs in boosting anammox activity within AnGS. Mechanistically, Fe 3 O 4 MPs released free iron, which anammox bacteria utilized to promote the synthesis of key enzymes, thereby enhancing their activity. Compared to MPs, Fe 3 O 4 NPs not only elevated the synthesis of these key enzymes to a higher level but also induced a nanofluids effect on the surface of AnGS, improving substrate permeability and accessibility to intragranular anammox bacteria. Moreover, the nanofluids effect was identified as the primary mechanism through which Fe 3 O 4 NPs enhanced anammox activity within AnGS. These findings provide new insights into the effects of nanoparticles on granular sludge systems, extending beyond AnGS., Competing Interests: The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (© 2024 The Authors.)

Objective: The cartilage regeneration field has not yet overcome the issue of effective "shaping": growing regenerated cartilage in the desired shape, and maintaining that shape, is problematic. This study reports on a new method of cartilage regeneration in which the cartilage is shaped in three dimensions. Since cartilage is composed only of cartilage cells and an abundant extracellular matrix with no blood circulation, once it is damaged, the lack of nutrient supply means that it is difficult to repair. Scaffold-free cell sheet technology plays an important role in cartilage regeneration, avoiding inflammation and immune response caused by scaffold materials. However, cartilage regenerated from the cell sheet needs to be sculpted and shaped before it can be used for cartilage defect transplantation., Design: In this study, we used a new ultra-strong magnetic-responsive Fe3O4 nanoparticle (MNP) to shape the cartilage in vitro . Super-magnetic Fe3O4 microspheres are manufactured by co-assembling negatively charged Cetyltrimethylammonium bromide (CTAB) and positively charged Fe3+ under solvothermal conditions., Results: The Fe3O4 MNPs are swallowed by chondrocytes, and the MNP-labeled chondrocytes are acted upon by the magnetic field. The predetermined magnetic force makes the tissues coalesce to form a multilayer cell sheet with a predetermined shape. The shaped cartilage tissue is regenerated in the transplanted body, and the nano magnetic control particles do not affect cell viability. The nanoparticles in this study improve the efficiency of cell interaction through super-magnetic modification, and to a certain extent change the way the cells absorb magnetic iron nanoparticles. This phenomenon allows a more orderly and compact alignment of the cartilage cell extracellular matrix, promotes ECM precipitation and cartilage tissue maturation, and improves the efficiency of cartilage regeneration., Conclusion: The magnetic bionic structure, which contains specific magnetic particle-labeled cells, is deposited layer by layer to generate a three-dimensional structure with repair function, and further induce the production of cartilage. This study describes a new method for the regeneration of tissue engineered cartilage which has broad application prospects in regenerative medicine., Competing Interests: Declaration of Conflicting InterestsThe author(s) declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article.

This work is an innovative study of ordered mesoporous silica (SBA-15) nanocomposites, with different morphologies, and superparamagnetic iron oxide nanoparticles (SPIONs), as promising drug delivery vehicles guided by magnetization. Incorporating SPIONs into SBA-15 is of great interest because it can improve controlled delivery of drugs as well as avoid agglomeration of the nanoparticles. SPIONs were prepared by coprecipitation and thermal decomposition methods and incorporated into SBA-15, with different morphologies, by the incipient wetness impregnation method. The nanocomposites (SBA-15:SPIONs) were characterized by physicochemical techniques, including small-angle X-ray scattering, X-ray diffraction, nitrogen adsorption–desorption isotherms, scanning and transmission electron microscopies, energy-dispersive spectroscopy, magnetization measurements, pair distribution function analysis, Fourier transform infrared spectroscopy, thermogravimetric analysis, and differential thermal analysis. The X-ray diffraction and small-angle X-ray scattering data of the nanocomposites verified that the crystalline phase of magnetite (Fe3O4) and the pore structure of the SBA-15 did not undergo significant changes. N2 physisorption data evidenced significant changes in the textural properties of the pure SBA-15, indicating the incorporation of SPIONs into the mesopores, with greater incorporation when the nanoparticles are obtained by thermal decomposition, in agreement with the small-angle X-ray scattering results. Transmission electron microscopy images, energy-dispersive spectroscopy, and thermogravimetry results evidence the successful incorporation of SPIONs into the silica matrix. The SBA-15:SPIONs presented superparamagnetic behavior. The pair distribution function method revealed a significant variation in the local structure related to changes in the Si–Si–O coordination caused by the decrease in the SBA-15 particle size. The incorporation of SPIONs was better for silica with smaller particle sizes and a higher proportion of SPIONs. Biological assays, such as myelotoxicity and cell viability, demonstrated that the nanocomposites could be safe potential drug delivery vehicles. [ABSTRACT FROM AUTHOR]

Magnetic nanoparticle-supported heterogeneous catalysts have been widely researched in green catalysis, due to their convenient magnetic separation and nanometer effects. Herein, a magnetic Co(III)-Salen heterogeneous catalyst with uniform spherical core-shell structure was synthesized for the chemical fixation of CO 2 into cyclic carbonate based on the sustainable protocol development and green chemistry principles. Fe 3 O 4 @SiO 2 nanoparticles with uniform spherical core-shell structure were prepared by the reverse microemulsion method, and Co(III)-Salen complexes were subsequently immobilized on the resulted Fe 3 O 4 @SiO 2 nanoparticles via covalent bonding, leading to Fe 3 O 4 @SiO 2 @Co(III)-Salen nanocomposites with particle size of 29 nm and saturation magnetization value of 27.2 emu/g. The catalytic performance study indicated that the catalyst exhibited high yield of 99% with selectivity of 100% for the ring-opening addition reaction of CO 2 and epoxide under solvent-free reaction condition. A plausible reaction mechanism was proposed that the Lewis acidic sites of Co(III)-Salen and nucleophilic bromine ion components played synergetic roles in promoting cycloaddition reactions. A stable geometry of the Co(III)-Salen complex and a detailed evidence for the reaction mechanism were provided by the density functional theory (DFT) calculations. Based on their excellent magnetic properties, the Co(III)-Salen nanocomposites could be easily recovered by using an external magnet and reused for 5 times without significant leaching of metal center and loss of catalytic activity. [ABSTRACT FROM AUTHOR]

Magnetite (Fe3O4) nanoparticles (NPs) are attractive nanomaterials in the field of material science, chemistry, and physics because of their valuable properties, such as soft ferromagnetism, half-metallicity, and biocompatibility. Various structures of Fe3O4 NPs with different sizes, geometries, and nanoarchitectures have been synthesized, and the related properties have been studied with targets in multiple fields of applications, including biomedical devices, electronic devices, environmental solutions, and energy applications. Tailoring the sizes, geometries, magnetic properties, and functionalities is an important task that determines the performance of Fe3O4 NPs in many applications. Therefore, this review focuses on the crucial aspects of Fe3O4 NPs, including structures, synthesis, magnetic properties, and strategies for functionalization, which jointly determine the application performance of various Fe3O4 NP-based systems. We first summarize the recent advances in the synthesis of magnetite NPs with different sizes, morphologies, and magnetic properties. We also highlight the importance of synthetic factors in controlling the structures and properties of NPs, such as the uniformity of sizes, morphology, surfaces, and magnetic properties. Moreover, emerging applications using Fe3O4 NPs and their functionalized nanostructures are also highlighted with a focus on applications in biomedical technologies, biosensing, environmental remedies for water treatment, and energy storage and conversion devices. [ABSTRACT FROM AUTHOR]

Polymyxin B (PMB) exert bactericidal effects on the cell wall of Gram-negative bacteria, leading to changes in the permeability of the cytoplasmic membrane and resulting in cell death, which is sensitive to the multi-resistant Gram-negative bacteria. However, the severe toxicity and adverse side effects largely hamper the clinical application of PMB. Although the molecular pathology of PMB neurotoxicity has been adequately studied at the cellular and molecular level. However, the impact of PMB on the physiological states of central nervous system in vivo may be quite different from that in vitro , which need to be further studied. Therefore, in the current study, the biocompatible ultra-uniform Fe3O4 nanoparticles were employed for noninvasively in vivo visualizing the potential impairment of PMB to the central nervous system. Systematic studies clearly reveal that the prepared Fe3O4 nanoparticles can serve as an appropriate magnetic resonance contrast agent with high transverse relaxivity and outstanding biosafety, which thus enables the following in vivo susceptibility-weighted imaging (SWI) studies on the PMB-treated mice models. As a result, it is first found that the blood-brain barrier (BBB) of mice may be impaired by successive PMB administration, displaying by the discrete punctate SWI signals distributed asymmetrically across brain regions in brain parenchyma. This result may pave a noninvasive approach for in-depth studies of PMB medication strategy, monitoring the BBB changes during PMB treatment, and even assessing the risk after PMB successive medication in multidrug-resistant Gram-negative bacterial infected patients from the perspective of medical imaging. [ABSTRACT FROM AUTHOR]

In this report, portable, quantitative, and sequential monitoring of copper ions and pyrophosphate (PPi) with a single sensor based on a DNAzyme-Fe3O4 system and glucometer readout was performed. Initially, streptavidin was functionalized on the surface of magnetic Fe3O4 spheres through glutaraldehyde. Then, an invertase-modified DNA Cu substrate was connected to the magnetic Fe3O4 spheres by a specific reaction between streptavidin and biotin. The sensing system was formed by a hybridization reaction between the Cu substrate and Cu enzyme. In the presence of Cu2+, Cu2+ will recognize the Cu DNA substrate and form an "off-on" signal switch, thereby resulting in the separation of invertase from the Fe3O4 nanospheres. PPi recognizes Cu2+ to form a Cu2+-PPi complex, resulting in an "on-off" signal switch. Under optimized conditions, linear detection ranges for Cu2+ and PPi of 0.01–5 and 0.5–10 μM, and detection limits for Cu2+ and PPi of 10 nM and 500 nM, respectively, were obtained. Good selectivity was achieved for the analysis of Cu2+ and PPi. Satisfactory results were achieved for this biosensor during the determination of Cu2+ in real tap samples and PPi in human urine samples. This verified that the sensor is portable and low cost, and can be applied to the sequential monitoring of multiple analytes with a single point-of-care biosensor. [ABSTRACT FROM AUTHOR]

Porous magnetite (Fe3O4) and hematite (α-Fe2O3) nanoparticles were prepared via the sol-gel auto-combustion method. The gels were prepared by reacting ferric nitrates (as oxidants) with starch (as fuel) at an elevated temperature of 200 °C. Different ratios (Φ) of ferric nitrates to starch were used for the synthesis (Φ = fuel/oxidant). The synthesized iron oxides were characterized by Fourier transform infrared (FT-IR) spectroscopy, Raman spectroscopy, X-ray diffraction (XRD) spectroscopy, scanning electron microscopy (SEM), transmission electron microscopy (TEM), Brunauer-Emmet-Teller (BET) and vibrating sample magnetometer (VSM) analysis techniques. The crystal structure, morphology, and specific surface area of the iron oxide nanoparticles (Fe3O4 and α-Fe2O3) were found to be dependent on the starch content. The FT-IR, XRD and VSM analysis of the iron oxides for Φ = 0.3 and 0.7 confirmed the formation of the α-Fe2O3 core, whereas at Φ = 1, 1.7, and 2 showed that Fe3O4 cores were formed with the highest saturation magnetization of 60.36 emu/g at Φ = 1. The morphology of the Fe3O4 nanoparticles exhibited a quasi-spherical shape, while α-Fe2O3 nanoparticles appeared polygonal and formed clusters. The highest specific surface area was found to be 48 m² g-1 for Φ = 1.7 owing to the rapid thermal decomposition process. Type II and type III isotherms indicated mesoporous structures. [ABSTRACT FROM AUTHOR]

Small glucose-modified liposomes (GMLs) were loaded with magnetic Fe3O4 nanoparticles (MNPs) and fluorescein using a standard thin layer preparation procedure and a varying lipid/MNPs ratio. The liposomes were characterized with TEM and DLS measurements, and MNPs encapsulation rate was determined using ICP-OES. Prepared liposomes were stored at 5 °C for 30 days and subsequently exposed to an external magnetic field (20 mT) with varying exposure times (2‒20 min), at room temperature. The release of fluorescein from GMLs induced by the magnetic field exposures was quantified, showing a high release rate (25‒85%) depending on the concentration of MNPs in GMLs. EPR measurements were conducted during the liposomes storage period in order to provide semi-quantitative information of possible MNPs oxidation from Fe3O4 to Fe2O3 inside the liposomes, impacting MNPs magnetic properties. In contrast to the MNPs water dispersion, no significant change in the EPR signal of MNPs encapsulated inside GMLs was detected over the course of 30 days. The data presented in this study indicate that GMLs loaded with MNPs maintain a high stability for prolonged periods of time and that this delivery system may be used for magnetically assisted controlled drug release. [ABSTRACT FROM AUTHOR]

Although laser-induced graphene (LIG) has great advantages in the cost and manufacturing process, it has been seldom reported in the field of electromagnetic interference (EMI) shielding due to its unobtrusive conductivity and the limitation of inherent substrates. In this work, polybenzoxazine is chosen as precursor to fabricate the LIG via a one-step defocused lasing process. As a result of favorable porous structures and high conductivity, the as-produced LIG exhibits the EMI shielding effectiveness up to 24.8 dB in X-band at the thickness of 68 μm. And the EMI shielding effectiveness of LIG/Fe 3 O 4 composite is increased to 32.7 dB at a smaller thickness of 53 μm which is obtained by a solvent-free approach. When considering the thickness and lightweight properties, the absolute shielding effectiveness is also surpassing most of the other carbon-based shielding materials. More importantly, taking advantage of the difference in the thermal expansion coefficient of carbon material and polymeric substrate, we develop a rapid quench-peeling (RQP) strategy for the separation of LIG from polymeric substrate to obtain the free-standing LIG film. Moreover, the structures and properties of LIG are well preserved. The free-standing LIG films after peeling have wider adaptability in practical EMI shielding applications, and also opened up possibilities for use in other fields, such as Joule heating device. [Display omitted] [ABSTRACT FROM AUTHOR]

Recently, pollen grains (PGs) have been introduced as drug carriers and scaffolding building blocks. This study aimed to assess the in-vitro biocompatibility of Pistacia vera L. hollow PGs/Fe3O4 nanoparticles (HPGs/Fe3O4NPs) composites using human adipose-derived mesenchymal stem cells (hAD-MSCs). In this regard, iron oxide nanoparticles (Fe3O4NPs) were assembled on the surface of HPGs at different concentrations. The biocompatibility of the prepared composites was assessed through MTT assay, apoptosis-related gene expression and field emission scanning electron microscopy (FE-SEM) analysis. Compared to the bare HPGs, the HPGs/Fe3O4NPs exhibited a biphasic impact on hAD-MSCs. The composite containing 1% Fe3O4NPs demonstrated no cytotoxicity up to 21 days while higher Fe3O4NPs contents and long-term exposure revealed adverse effects on the hAD-MSCs' growth. The obtained result was verified by the qRT-PCR and morphological analysis carried out through FE-SEM which suggests that a narrow region below 1% Fe3O4NPs may be the optimum choice for medicinal applications of HPGs/Fe3O4NPs microdevices. [ABSTRACT FROM AUTHOR]

New polymer-coated magnetic nanocarrier using magnetic iron oxide nanoparticles coated with chitosan and nanohydroxyapatite extracted from Sea urchin that both have anti-cancer properties showed good ability to Methotrexate (MTX) delivery. Iron oxide nanoparticles and hydroxyapatite prepared by co-precipitation and hydrothermal methods respectively. To stabilize the nanoparticles and optimization of the nanoparticles with hydroxyapatite, 3-chloropropyltrioethoxysilane and chitosan were performed. The water-soluble anticancer drug Methotrexate was selected as the drug model. The drug loading percentage was % 86.66, loading efficiency was % 99.5 and the polydispersity of the nanoparticles was 0.01. The kinetic pattern of drug release is consistent with the Peppas equation and the results of the thermal analysis confirm the stability of the crystalline form of the drug. The FTIR results and FE-SEM images showed that the nanoparticles were successfully prepared and coated and their size ranged from 30 nm to 1.5μm. The VSM analysis confirms the magnetic properties of the nanoparticles and the magnetic indices for the magnetic nanocarrier and the magnetic nanocarrier carrying MTX are 23 and 19 emu/g–1, respectively. The present study demonstrates the potential of iron oxide nanoparticles for the design of new magnetic nanocarrier and for guiding Methotrexate drug therapy in cancer chemotherapy. [ABSTRACT FROM AUTHOR]

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Polymyxin B (PMB) exert bactericidal effects on the cell wall of Gram-negative bacteria, leading to changes in the permeability of the cytoplasmic membrane and resulting in cell death, which is sensitive to the multi-resistant Gram-negative bacteria. However, the severe toxicity and adverse side effects largely hamper the clinical application of PMB. Although the molecular pathology of PMB neurotoxicity has been adequately studied at the cellular and molecular level. However, the impact of PMB on the physiological states of central nervous system in vivo may be quite different from that in vitro, which need to be further studied. Therefore, in the current study, the biocompatible ultra-uniform Fe3O4 nanoparticles were employed for noninvasively in vivo visualizing the potential impairment of PMB to the central nervous system. Systematic studies clearly reveal that the prepared Fe3O4 nanoparticles can serve as an appropriate magnetic resonance contrast agent with high transverse relaxivity and outstanding biosafety, which thus enables the following in vivo susceptibility-weighted imaging (SWI) studies on the PMB-treated mice models. As a result, it is first found that the blood-brain barrier (BBB) of mice may be impaired by successive PMB administration, displaying by the discrete punctate SWI signals distributed asymmetrically across brain regions in brain parenchyma. This result may pave a noninvasive approach for in-depth studies of PMB medication strategy, monitoring the BBB changes during PMB treatment, and even assessing the risk after PMB successive medication in multidrug-resistant Gram-negative bacterial infected patients from the perspective of medical imaging.

In this paper, the extract of Citrus aurantium (CA) was used as a green approach for the preparation of Fe3O4 nanoparticles. The green Fe3O4 (Fe3O4/CA) was characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy analysis (EDX), Fourier-transform infrared (FTIR) spectroscopy, Brunauer–Emmett–Teller (BET) surface area measurement, and vibrating sample magnetometry (VSM). The synthesized Fe3O4/CA was used to remove methylene blue (MB) dye from an aqueous solution. A four-factor central composite design (CCD), combined with response surface modeling (RSM), was used to maximize the MB dye removal. The four independent variables, which were initial dye concentration (10–50 mg/L), solution pH (3–9), adsorbent dose (ranging from 200–1000 mg/L), and contact time (30–90 min), were used as inputs to the model of the perecentage dye removal. The results yielded by an analysis of variance (ANOVA) confirmed the high significance of the regression model. The predicted values of the MB dye removal were in agreement with the corresponding experimental values. Optimized conditions for the maximum MB dye removal (93.14%) by Fe3O4/CA were the initial dye concentration (10.02 mg/L), pH (8.98), adsorbent mass (997.99 mg/L), and contact time (43.71 min). The validity of the quadratic model was examined, and good agreement was found between the experimental and predicted values. Our findings demonstrated that green Fe3O4NPs is a good adsorbent for MB removal.

The aim of this study is to evaluate the applicability of the catalytic activity (CA) of the Fe3O4 magnetic system in the adsorption/degradation of methylene blue and esterification. The thermal decomposition method allowed the preparation of Fe3O4 nanoparticles. The crystallites of the Fe3O4 structural phase present an acicular form confirmed by X-ray diffraction. Transmission electron microscopy results identified the acicular shape and agglomeration of the nanoparticles. Mössbauer spectroscopy showed that the spectrum is composed of five components at room temperature, a hyperfine magnetic field distribution (HMFD), two sextets, a doublet, and a singlet. The presence of the HMFD means that a particle size distribution is present. Fluorescence spectroscopy studied the CA of the nanoparticles with methylene blue and found adsorption/degradation properties of the dye. The catalytic activity of the nanoparticles was evaluated in the esterification reaction by comparing the results in the presence and absence of catalyst for the reaction with isobutanol and octanol, where it is observed that the selectivity for the products MIBP and MNOP is favored in the first three hours of reaction.

A series of new composite materials based on Fe3O4 magnetic nanoparticles coated with SiO2 (or aminated SiO2) were synthesized. It has been shown that the use of N-(phosphonomethyl)iminodiacetic acid (PMIDA) to stabilize nanoparticles before silanization ensures the increased content of a SiO2 phase in the Fe3O4@SiO2 nanocomposites (NCs) in comparison with materials obtained under similar conditions, but without PMIDA. It has been demonstrated for the first time that the presence of PMIDA on the surface of NCs increases the level of Dox loading due to specific binding, while surface modification with 3-aminopropylsilane, on the contrary, significantly reduces the sorption capacity of materials. These regularities were in accordance with the results of quantum chemical calculations. It has been shown that the energies of Dox binding to the functional groups of NCs are in good agreement with the experimental data on the Dox sorption on these NCs. The mechanisms of Dox binding to the surface of NCs were proposed: simultaneous coordination of Dox on the PMIDA molecule and silanol groups at the NC surface leads to a synergistic effect in Dox binding. The synthesized NCs exhibited pH-dependent Dox release, as well as dose-dependent cytotoxicity in in vitro experiments. The cytotoxic effects of the studied materials correspond to their calculated IC50 values. NCs with a SiO2 shell obtained using PMIDA exhibited the highest effect. At the same time, the presence of PMIDA in NCs makes it possible to increase the Dox loading, as well as to reduce its desorption rate, which may be useful in the design of drug delivery vehicles with a prolonged action. We believe that the data obtained can be further used to develop stimuli-responsive materials for targeted cancer chemotherapy.

Active rheology control (ARC) or active stiffening control (ASC) is a concept with which the conflicting rheological requirements during different stages of concrete casting can be reconciled. For instance, formwork leakage could be reduced by actively controlling structuration at the formwork joints, without having the negative impact of increased structuration during pumping and form filling. Using the concepts of magnetorheology, an active control methodology was thus recently developed by the authors to study the control of formwork leakages under pressure. This was performed using a small-scale laboratory test setup, using cementitious pastes containing magnetisable particles. To upscale from paste to mortar, the effect of volume fraction of sand on the magnetorheological (MR) response and blocking mechanisms of mixtures containing Fe3O4 nanoparticles is thus investigated in the current study. The MR response is determined using storage modulus tests, and the impact of ASC for leakage reduction is investigated by measuring the flow rate. Experimental results show that increasing the sand volume beyond a threshold causes a reduction in mobility of the magnetic particles, and thus lowers the MR effect. Despite this reduction in the MR effect at high sand volume, the increased particle interactions induce clogging and filtration effects, drastically lowering the flow rate. Applying the ASC method refines the voids in the clog, thereby eliminating the filtration effect. It is concluded that ASC can be used on mortar, with the expectation that there would be a reduction in the magnetorheological effect with increasing volume of fine aggregates.

Solar desalination devices utilizing sustainable solar energy and the abundant resource of seawater has great potential as a response to global freshwater scarcity. Herein, a bilayered solar evaporator was designed and fabricated utilizing a facile paper sheet forming technology, which was composed of cellulose fibers decorated with Fe3O4 nanoparticles as the top absorbent layer and the original cellulose fibers as the bottom supporting substrate. The characterization of the cellulose fibers decorated with Fe3O4 nanoparticles revealed that the in situ formed Fe3O4 nanoparticles were successfully loaded on the fiber surface and presented a unique rough surface, endowing the absorber layer with highly efficient light absorption and photothermal conversion. Moreover, due to its superhydrophilic property, the cellulose fiber-based bottom substrate conferred ultra-speed water transport capability, which could enable an adequate water supply to combat the water loss caused by continuous evaporation on the top layer. With the advantages mentioned above, our designed bilayered paper-based evaporator achieved an evaporation rate ~1.22 kg m−2 h−1 within 10 min under 1 sun irradiation, which was much higher than that of original cellulose cardboard. Based on the simple and scalable manufacture process, the bilayered paper-based evaporator may have great potential as a highly efficient photothermal conversion material for real-world desalination applications.

The emerging nano biosystems are competent in diagnosis, drug delivery, and monitoring of therapeutic response. Both imaging and therapeutic functions can be achieved by using nanoplatforms. These nanoplatforms promise to revolutionize the medical management of many personalized illnesses. The well-developed surface chemistry of iron oxide (Fe3O4) makes it easy to charge them with pharmaceutics, promoting them as nanoplatforms for building up nanoparticle-based drug delivery systems. The strategy to design multifunctional Fe3O4 conjugates with bioactive molecules of plant origin to show enhanced activity is reported here. The conjugation reveals the magnetic Fe3O4 core nanoparticle surface readily link to hydroxyl sites of the Dextrin molecule, which further conjugate to conjugated with Curcumin and D-Limonene, which are powerful anti-cancer, anti-inflammatory, and antioxidant agents. The structural, morphological, optical, and magnetic properties were analyzed by X-ray diffraction, FT-Infrared, HR-Tunneling Electron Microscopy, and Vibrating Sample Magnetometer techniques. The potential drug loading was measured as Drug Entrapment Efficiency using UV-Vis spectroscopy. The antibacterial property was tested on the bacterium S. aureus and E. coli. Fe3O4-Dextrin nanoconjugates proved to be efficient for loading and stabilizing Curcumin and Limonene. Thus, multifunctional Fe3O4 conjugates are explored as exciting nano-drug carriers for targeted drug delivery. [ABSTRACT FROM AUTHOR]

The fabrication of the inorganic metal oxide nanoparticles by using extract of the different part of the plant was gaining an overwhelming response from the last few years. Magnetic iron oxide nanoparticles exhibiting verity of biomedical applications hence in the current proposed work we use an unexplored Euphorbia herita leaf extract in the green synthesis of magnetic iron oxide nanoparticles (Fe3O4 NPs). The tailored Fe3O4 NPs was structurally characterized by using advanced analytical tools like UV–visible spectroscopy, Scanning electron microscopy (SEM) analysis, Fourier transform infra-red (FT-IR) analysis and X-ray diffraction study. The fabricated nanoparticles were naturally stabilized, having cavity like structure with average particle size in the range of 25–80 nm. The phytochemicals especially polyphenols and alcoholic compound play crucial role in the fabrication of magnetic iron oxide nanoparticles. The antimicrobial activity of the fabricated iron oxide nano particles was evaluated against selected bacterial and fungal pathogen and the result of antimicrobial study was very promising. [ABSTRACT FROM AUTHOR]

Fluoride contamination in drinking water is one of the major problems worldwide imposing a serious threat to human health. For fluoride removal, the superparamagnetic Fe3O4 nanoparticles (Fe3O4 NPs) were successfully synthesized in a non-aqueous medium through a simple and facile hydrothermal reduction route. These nanoparticles had a mesoporous structure with a specific surface area of 70.14 m2 g-1. Fluoride adsorption behavior was investigated and the optimization of several experimental parameters was explored. The adsorption properties of the sample were excellent. The adsorption capacity could reach up to 70.64 mg g-1 at 25°C when the initial fluoride concentration was 200 mg L-1. Kinetic data were consistent with the pseudo-second-order model and also indicated the adsorption process was limited by the pore diffusion. The adsorption isotherms were found fitting well with the Freundlich model. The presence of bicarbonate, carbonate, and phosphate adversely affected the adsorption of fluoride. The revelation of the adsorption mechanism was based on Fourier transform infrared spectroscopy, X-ray photoelectron spectroscopy analysis, and zeta potential study. The results showed the surface hydroxyl groups and sulfate anions played important roles in the fluoride removal. In the magnetic hysteresis curves, the Fe3O4 nanoparticles exhibited a superparamagnetic characteristic with a saturation magnetization of 29.86 emu g-1, which was beneficial for magnetic separation. [ABSTRACT FROM AUTHOR]

The significance of sulfasalazine (SSZ) as a therapeutic agent has garnered paramount research interest in the design and fabrication of a viable sensor for the detection of SSZ. Herein, we demonstrate a new strategy for the sensitive determination of SSZ employing single walled carbon nanotubes decorated with Fe3O4 nanoparticles sensing platform for the first time. The synthesized Fe3O4 nanoparticles and the surface morphology of the developed sensor were investigated by exerting various analytical techniques. The optimization of operational parameters was effectuated. The developed sensor exhibited pronounced electrocatalytic activity for the electro oxidation of SSZ in the dynamic detection range of 25 nM–1.5 μM manifesting noteworthy high sensitivity and phenomenal low detection limit of 18.6 μA μM−1 and 1.6 nM respectively. Apparent specificity in the presence of interferents along with remarkable stability and reproducibility were attained by the sensor. The prominence of the developed methodology was emphasized by the determination of SSZ in pharmaceutical formulations. Furthermore, the applicability of the developed electrode was established by utilizing it effectually for the first time to quantify SSZ in serum sample of patients undergoing pharmacological treatment for rheumatoid arthritis. [ABSTRACT FROM AUTHOR]

Firstly, magnetic Fe3O4 nanoparticles are prepared by solvothermal method and then coated with SiO2 to form Fe3O4@SiO2 core-shell magnetic nanomaterials. Fe3O4@SiO2 core-shell magnetic nanomaterials are characterized by XRD, SEM, TEM, magnetic properties and adsorption properties. The results show that Fe3O4@SiO2 core-shell magnetic nanomaterials have two crystal structures of Fe3O4 and SiO2. SiO2is successfully coated on the magnetic Fe3O4 nanoparticles and has no significant effect on the structure and composition of each structure. The particle size of Fe3O4@SiO2 core-shell magnetic nanomaterials is about 200 ~ 400 nm and the structure is core-shell. The color of Fe3O4 nanoparticles in the inner layer is darker but that of SiO2 in the outer layer is lighter. The saturation magnetization of Fe3O4@SiO2 core-shell magnetic nanomate rials is 76.31 A. m²/kg at room temperature and the remanent magnetization is almost zero. The adsorption of Cu (II) on Fe3O4@SiO2 core-shell magnetic nanomaterials reaches saturation at 1500 min. The highest removal rate is 6:3 % and the maximum adsorption capacity is 120 mg/g. It has a good adsorption effect on Cu (II). [ABSTRACT FROM AUTHOR]

In this work the interaction characteristics of nucleobases with As(III) are studied. Novel materials consisting of magnetic nanoparticles (MNPs) functionalized with adenine hydrazide (AH), guanine hydrazide (GH) and uracil hydrazide (UH) were elaborated. The adsorption isotherms were investigated electrochemically and it was shown that the adsorption capacity of the nanoparticles towards arsenic (III) increased in the following order: AH

[Display omitted] • A facile and up-scalable method was proposed to disperse Fe grains on BC nanofibers. • No organic solvents or toxic reagents was used in BC-induced hydrolytic deposition. • The inherited networks of CBC favor the transmission of both electrons and ions. • The space created by intertwined CBC fibers accommodate the volume changes of Fe 3 O 4. • The free-standing Fe 3 O 4 /CBC anodes show decent electrochemical performances in LIBs. An extremely facile and up-scalable approach has been proposed to disperse ferric grains onto bacterial cellulose (BC) nanofibers. The BC-induced hydrolytic deposition can be performed at room temperature without using any organic solvents, toxic reagents, or complicated apparatuses, enabling a green pathway in realizing industrialization. After carbonization, the randomly oriented carbonized BC (CBC) nanofibers transmit the electrons throughout the electrode, while the inherited reticular morphology boosts the thorough penetration of electrolyte. Moreover, the sufficient space created by interconnected CBC nanofibers is able to accommodate the volume change of the nanosized Fe 3 O 4 active materials during repeated Li+ intercalation and deintercalation. As a result, the as-prepared Fe 3 O 4 /CBC composites deliver the superior electrochemical performance as the free-standing anodes in Li-ion batteries (LIBs), including the impressive reversible capacity of 702 mAh g−1 after 400 cycles at 400 mA g−1, decent rate capability with capacity of 437 mAh g−1 at 2000 mA g−1, and a long cycling lifespan up to 1000 cycles at 800 mA g−1. This work provides a scalable and green approach to fabricate high-performance LIBs anode with the natural sustainable biomass. [ABSTRACT FROM AUTHOR]

Objective: To explore the synergistic effect of Fe3O4 nanoparticles (PION), as a drug carrier, on enhancing the effect of chlorin e6 (Ce6) in glioma. Methods: PEG-Fe3O4@Ce6 composite nanoparticles (PION@E6) were prepared by high temperature degradation method and phase transfer method, and then verified by hydrated particle size analysis, transmission electron microscopy, colloidal stability analysis and ultraviolet-visible light absorption spectroscopy, etc. CCK-8 method was used to detect the proliferation activity of glioma U251 cells, Flow cytometry was used to detect the apoptosis of the cells, and the DCFH-DA probe method was used to detect the level of reactive oxygen species (ROS) in the cells. Glioma U251 cell transplanted tumor model was constructed on BALB/c-nu nude mice. The retention time of PION@E6 and Ce6 in transplanted tumors was observed with animal fluorescence imaging technology and magnetic resonance imaging (MRI), and the survival and tumor volume on the 28th day in the PION@E6 sonodynamic therapy group and Ce6 sonodynamic therapy group were compared. Results: Transmission electron microscopy and hydrated particle size analysis showed that the core particle size of PION@E6 was 10 nm and the hydrated particle size was (37.86±12.90) nm; colloidal stability analysis showed that PION@E6 had good water solubility and stability; and the absorption spectrum and XRD atlas showed that Ce6 had been loaded on Fe3O4 nanoparticles. Compared with the Ce6 sonodynamic group, the proliferation activity of U251 cells in the PION@E6 sonodynamic group was significantly decreased (P<0.05), the apoptosis rate was significantly increased (all P<0.05), and the level of ROS in the cells was significantly increased (P<0.05). In vivo experiments on nude mice bearing glioma U251 cell transplanted tumors showed that compared with Ce6 sonodynamic therapy group, the retention time of Ce6 in the transplanted tumor tissues of the PION@E6 sonodynamic therapy group was significantly prolonged (P<0.05), the number of survived nude mice was significant increased, and the transplanted tumor volume was significantly reduced (P<0.01). Conclusion: Fe3O4 nanoparticles have a significant synergistic effect on Ce6-mediated sonodynamic therapy of glioma U251 cells. [ABSTRACT FROM AUTHOR]

liquid marbles are liquid droplets that encapsulated with hydrophobic micro-nano sized particles. These liquid soft solids, as a promising digital microfluidic systems, offer a simple alternative to conventional discrete microfluidic systems and may have wide applications in biomedical, biochemistry and nanotechnology. In this experimental and numerical study, first, for production of magnetic liquid marbles, Fe3O4 magnetic nanoparticles were synthesized and hydrophobized with paraffin wax. Second, by slight rolling of water droplet on Fe3O4@Isoleucine-P wax nanoparticles, the formation of our magnetic liquid marble is achieved. Third by modeling our liquid marble by a droplet with an elastic shell, the effect of gravity on marble shape simulated and verified with experimental results. The results obtained from the simulation analysis fit well to the experimental data describing the shape of liquid marble under the force of gravity. [ABSTRACT FROM AUTHOR]

A dual stimuli-responsive magnetic nanohydrogel was fabricated as a potent drug delivery system (DDS) for 'smart' treatment of cancer by chemo/hyperthermia approach. For this objective, Fe3O4 nanoparticles (NPs) were produced via a co-precipitation approach and then modified by 3-(trimethoxysilyl) propylmethacrylate (MPS) moiety. The modified NPs were copolymerized with N,N′-(dimethylamino)ethyl methacrylate (DMAEMA), and maleic anhydride (MA) monomers by a free radical polymerization approach to afford a Fe3O4@P(DMAEMA-co-MA) core-shell NPs. Afterward, the NPs were shell crosslinked by the reaction of anhydride unites with neutralized cystamine (Cys). The fabricated pH- and reduction-responsive magnetic nanohydrogel was physically loaded with methotrexate (MTX), as an anticancer drug, and its drug loading efficiency (LE) was calculated as 64 ± 2.7%. The developed nanohydrogel/MTX exhibited proper stimuli-triggered drug release behavior that qualified it as an efficient DDS according to the abnormal micro-environment of cancerous tumors. The anticancer activity investigation using chemo/hyperthermia therapy approach by MTT-assay revealed that the nanohydrogel/MTX might show better clinical outcomes than those of the free MTX. [ABSTRACT FROM AUTHOR]

Copyright of Materials & Technologies / Materiali in Tehnologije is the property of Institute of Metals & Technology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Herein, photocurrent generating a millimeter‐scale bioelectrochemical cell (mBEC) is fabricated using a thylakoid membrane (TM) on a screen‐printed electrode (SPE). The mBEC is used to generate a direct and mediated photocurrent without using a selective membrane. The mediated photocurrent generation is tested with iron oxide nanoparticles (NPs) coated on the SPE surface and the water soluble mediators potassium hexacyanoferrate (FCN) and p‐Benzoquinone (BQ). The SPE/TM system produces a 4.35 μA cm−2 photocurrent without using a mediator obtained by direct electron transfer (DET). A significant enhancement reaches the current generation when an efficient amount of mediator is used in the system. The SPE/NP/BQ/TM system produces a 55 μA cm−2 photocurrent with an incorporation among TM, NP, and BQ. The performance of the mBECs is tested by taking the measurements from series and parallel connected cells. An enhanced photocurrent generation of 178 μA cm−2 is attained when the four cells are connected in series. Also, a higher light conversion rate is achieved by the parallel connected two cells. In addition, the maximum current density of mBEC obtained from the SPE/NP/BQ/TM cell at a pseudo‐steady state is 180 mA m−2 at a power density of 40 mWm−2. [ABSTRACT FROM AUTHOR]

• Silicone surfactant. • Viscosity change of MF is only 13.9%. • Stable for over 2 months. The Fe 3 O 4 magnetic nanoparticles were prepared using a chemical co-precipitation and were coated with surface-active agents including silane coupling agents KH550 and KH792, carboxyl-functionalized silicone oil, and amine-functionalized silicone oil. In this study, the four types of magnetic nanoparticles coated with different surface-active agents were characterized using XRD, FTIR, TEM, VSM, etc. to determine the effects of different surface-active agents on the magnetic nanoparticles. Furthermore, four different types of silicone oil-based colloidal magnetic fluids were prepared, and their stability was analyzed using an LC oscillation circuit. The results show that the magnetic nanoparticles coated with carboxyl-functionalized silicone oil have an average particle size of about 12.4 nm and a saturation magnetization of 65.2 emu/g. They exhibit the strongest dispersion stability in the base fluid, and the prepared silicone oil-based colloidal magnetic fluids can remain stable under a magnetic field for up to 2 months without sedimentation. Moreover, they exhibit excellent viscosity-temperature performance, which enhances the practical application value of silicone oil-based colloidal magnetic fluids. [ABSTRACT FROM AUTHOR]

Combination of different therapies is an attractive approach for cancer therapy. However, it is a challenge to synchronize different therapies for maximization of therapeutic effects. In this work, a smart composite scaffold that could synchronize magnetic hyperthermia and chemotherapy was prepared by hybridization of magnetic Fe 3 O 4 nanoparticles and doxorubicin (Dox)-loaded thermosensitive liposomes with biodegradable polymers. Irradiation of alternating magnetic field (AMF) could not only increase the scaffold temperature for magnetic hyperthermia but also trigger the release of Dox for chemotherapy. The two functions of magnetic hyperthermia and chemotherapy were synchronized by switching AMF on and off. The synergistic anticancer effects of the composite scaffold were confirmed by in vitro cell culture and in vivo animal experiments. The composite scaffold could efficiently eliminate breast cancer cells under AMF irradiation. Moreover, the scaffold could support proliferation and adipogenic differentiation of mesenchymal stem cells for adipose tissue reconstruction after anticancer treatment. In vivo regeneration experiments showed that the composite scaffolds could effectively maintain their structural integrity and facilitate the infiltration and proliferation of normal cells within the scaffolds. The composite scaffold possesses multi-functions and is attractive as a novel platform for efficient breast cancer therapy. [Display omitted] [ABSTRACT FROM AUTHOR]

Superhydrophobic coatings are ideal for industrial applications involving oil spill cleaning, de-icing, anti-fouling, and anti-icing. The majority of current superhydrophobic coating preparation techniques have significant costs and pollute the environment, which are incompatible with the principles of sustainable green development. In this study, we produced a superhydrophobic coating based on the low-cost green material chitosan, Fe 3 O 4 nanoparticles, and octadecylamine, which possesses photothermal characteristics and magnetic oil-water separation properties. Among these, octadecylamine supplied a lower surface energy and nano-Fe 3 O 4 supplied the coating's surface roughness structure. Under simulated sunlight, the fabricated coatings produced a pronounced photothermal effect. The surface temperatures of the polyurethane sponge coating and the cotton fabric coating rose to 144.6 °C and 117.5 °C, respectively, after just 5 min. Furthermore, the coatings can be used for magnetically-driven oil-water separation with a certain degree of recyclability. The oil-water separation efficiency of the coating can reach 92% and above. More importantly, the coating also has excellent mechanical stability and self-cleaning properties. Therefore, this cheap and environmentally friendly nano-Fe 3 O 4 /chitosan-based superhydrophobic coating has great potential for application. [Display omitted] [ABSTRACT FROM AUTHOR]

• ●A magnetic-responsive Fe 3 O 4 @SiO 2 -MPS-PILs were synthesized. • ●The material possessed abundant imidazole units, benzene rings and ionic bonds. • ●The adsorbent could simultaneously remove iodine and iodide ions from solutions. • ●The material maintained over 90% of the uptake capacity after five cycles. Nuclear waste management and nuclear energy generation require the proper disposal of 129I and 131I, which are radioactive isotopes of iodine. For recognition of different types' iodine, a magnetic poly (ionic liquid)s (Fe 3 O 4 @SiO 2 -MPS-PILs) was formed by the selected imidazole ionic liquid monomer and core–shell Fe 3 O 4 @SiO 2 -MPS via free radical polymerization. The resulting adsorbent containing plenty of imidazole N-heterocycle units, benzene rings, and ionic bonds in the backbones was suitable for simultaneously adsorbing iodine molecules and iodide ions. The adsorption mechanisms for iodine in cyclohexane and iodide ions from aqueous solution were based on charge transfer and ion exchange mechanisms, respectively. The adsorption equilibrium for iodine in cyclohexane was attained at 12 h, and the kinetics of iodine adsorption closely followed the pseudo-second-order model. Iodine adsorption on Fe 3 O 4 @SiO 2 -MPS-PILs was best described by Langmuir model with a maximum iodine adsorption capacity of approximately 714.29 mg g−1. Iodide ions adsorption was best explained with Freundlich model and a maximum adsorption capacity of 335.80 mg g−1 was achieved in an iodide solution with a 500 mg L–1 concentration. Notably, Fe 3 O 4 @SiO 2 -MPS-PILs retained over 90 % of its original adsorption performance after the 5th cycle. This work proves that the adsorbent Fe 3 O 4 @SiO 2 -MPS-PILs was efficient and recyclable, and has good application prospects in the practical treatment of iodine and iodide. [ABSTRACT FROM AUTHOR]