Fe3O4 Core Shell Research Articles

Infection microenvironment-triggered nanoparticles eradicate MRSA by thermally amplified chemodynamic therapy and M1 macrophage

It is of great significance to develop a novel approach to treat bacterial infections, as the frequent misuse of antibiotics leads to the serious problem of bacterial resistance. This study proposed antibiotic-free antibacterial nanoparticles for eliminating methicillin-resistant Staphylococcus aureus (MRSA) based on a multi-model synergistic antibacterial ability of chemodynamic therapy (CDT), photothermal effect, and innate immunomodulation. Specifically, a polydopamine (PDA) layer coated and Ag nanoparticles loaded core-shell structure Fe3O4 nanoparticles (Fe3O4@PDA-Ag) is prepared. The Fe3O4 catalyzes H2O2 present in acidic microenvironment of bacterial infection into more toxic reactive oxygen species (ROS) and synergizes with the released Ag ions to exert a stronger bactericidal capacity, which can be augmented by photothermal action of PDA triggered by near-infrared light and loosen the biofilm by photothermal action to promote the penetration of ROS and Ag ion into the biofilm, result in disrupting biofilm structure along with killing encapsulated bacteria. Furthermore, Fe3O4@PDA-Ag exerts indirect antibacterial effects by promoting M1 macrophage polarizing. Animal models demonstrated that Fe3O4@PDA-Ag effectively controlled MRSA-induced infections through photothermal enhanced CDT, Ag+ releasing, and macrophage-mediated bactericidal properties. The acid-triggered antibacterial nanoparticles are expected to combat drug-resistant bacteria infection.Graphical abstract

Poorly-/well-dispersed Fe3O4: Abnormal influence on electromagnetic wave absorption behavior of high-mechanical performance polyurea

In this work, novel core–shell Fe3O4 nanoparticles were prepared by self- assembly technology using phytate-melamine aggregates (PM) or phytate-melamine-Fe3+ aggregates (PM-Fe) as building block. A polyurea (PUA) matrix was filled with magnetic nanoparticle. The influence of Fe3O4, Fe3O4@PM or Fe3O4@PM-Fe content and dispersion on the mechanical and electromagnetic wave (EMW) absorption properties of PUA composite were investigated. Good dispersion of modified Fe3O4 in PUA matrix was obtained. Loading well-dispersed Fe3O4 significantly enhanced the mechanical properties of their PUA nanocomposite under quasi-static tensile, nanoindentation, and dynamic compression tests. Excellent EMW absorption performance of PUA/Fe3O4@PM nanocomposite was desired. Although well-dispersed Fe3O4@PM could effectively enhance the mechanical properties, nonetheless it surprisingly plays a negative role in the EMW absorption performance. The Fe3O4@PM with high dispersion and interfacial compatibility in the PUA matrix was detrimental to EMW absorption performance, which contradicts the well accepted EMW absorption mechanisms. A novel mechanism and model were suggested, along with a fresh understanding of the role of Fe3O4 in the EMW absorption of PUA composite. Furthermore, the Fe3O4@PM-Fe, obtained by constructing a conductive network on the surface of Fe3O4@PM, was used to investigate this assumption. The radar cross section simulation also demonstrated the superior EMW attenuation capability of PUA nanocomposites in the service condition. This work is beneficial to the development of EMW absorber, not limited to Fe3O4 magnetic nanoparticles.

Assembly of core-shell Fe3O4 @CD-MOFs derived hollow magnetic microcubes for efficient extraction of hazardous substances: Plausible mechanisms for selective adsorption

Hazardous heavy metals and organic substances removal is of great significance for ensuring the safety of aquatic-ecosystem, yet the highly effective and selective extraction always remains challenging. To address this problem, magnetic hollow microcubes were fabricated through thermal carbonization of Fe3O4-COOH@ γ-CD-MOFs, and core-shell structured precursors were in-situ greenly constructed on a large scale via microwave-assisted self-assembly strategy. As noted, the development of secondary crystallization was utilized to achieve uniform dispersion of cores within MOFs frameworks and thus improved magnetic and adsorption ability of composites. Acquired magnetic Fe3O4 @HC not only can harvest excellent extraction of heavy metals (Cd, Pb, and Cu of 129.87, 151.05, and 106.98 mg·g−1) but also exhibit highly selective adsorption ability for cationic organics (separation efficiency higher than 95.0 %). Impressively, Fe3O4 @HC achieved outstanding adsorption (60–80 %) of Cd in realistic mussel cooking broth with no obvious loss in amino acid. Characterizations better offer mechanistic insight into the enhanced selectivity of positively charged pollutants can be attributed to synergistic effect of ions exchange and electrostatic interaction of abundant oxygen-containing functional groups. Our study provides a feasible route by rationally developing core-shell structured composites to promote the practical applications of sustainable water treatment and value-added utilization of processing by-products.

Preparation and Characterization of C@Fe3O4 Supported Pd Magnetic Nanoparticles for Degradation of Dye Wastewater

The core-shell structure Fe3O4@C magnetic nanoparticles were synthesized with superparamagnetic Fe3O4 nanosphere as a magnetic core, and soluble starch resin as a carbon source via a solvothermal method. Silica-iron oxide and Fe3O4@C carriers with a core-shell structure were prepared by carbonization of organic material on the surface of Fe3O4 nanoparticles, Fe3O4@C supported Pd were processed into magnetic nano-catalysts with core-shell structure, and their catalytic properties were investigated. The resulting environmentally friendly magnetic material can be used to degrade dye wastewater. The structure of magnetic nanoparticles was characterized using TEM, XRD and VSM. The effects of preparation conditions in the structure of the Fe3O4@C magnetic nanoparticles were taken out. The results indicate that from XRD, the magnetic nano particles Fe3O4@C synthesized of carbon sources have amorphous carbon diffraction peak except for all the characteristic peaks of Fe3O4. The saturation magnetization Fe3O4, Fe3O4@SiO2 and Fe3O4@C – 59.14 emu/g, 49.12 emu/g and 27.95 emu/g, respectively.

Thermal conductivity and photothermal characteristic of core-shell Fe3O4@C nanofluids in different particle size

Instability is a key issue that limits the application of magnetic nanofluids. In this study, Fe3O4@C nanoparticles were obtained using a carbon layer coated with a ferromagnetic material, which improved the instability of the magnetic nanofluid while obtaining higher thermal conductivity and showed excellent photothermal conversion performance in photothermal conversion experiments. Firstly, we prepared Fe3O4@C nanoparticles via the solvothermal method. We then compared different sizes of Fe3O4@C nanoparticles in terms of structure, composition, heat transfer characteristics and photothermal efficiency. The results indicate that contrary to the conventional belief that smaller nanoparticles have higher thermal conductivity, the 90.30 nm Fe3O4@C nanofluids has better thermal conductivity than 58.17 nm due to its larger proportion of carbon shells. In the photothermal conversion experiment for DASCs, the 58.17 nm group performed best, with the temperature of the 0.2 wt% sample reaching 45.80 °C and a photothermal efficiency of 60.32%.

Core-Shell Fe3O4@C Nanoparticles as Highly Effective T2 Magnetic Resonance Imaging Contrast Agents: In Vitro and In Vivo Studies.

Magnetite nanoparticles (Fe3O4 NPs) have been intensively investigated because of their potential biomedical applications due to their high saturation magnetization. In this study, core-shell Fe3O4@C NPs (core = Fe3O4 NPs and shell = amorphous carbons, davg = 35.1 nm) were synthesized in an aqueous solution. Carbon coating terminated with hydrophilic -OH and -COOH groups imparted excellent biocompatibility and hydrophilicity to the NPs, making them suitable for biomedical applications. The Fe3O4@C NPs exhibited ideal relaxometric properties for T2 magnetic resonance imaging (MRI) contrast agents (i.e., high transverse and negligible longitudinal water proton spin relaxivities), making them exclusively induce only T2 relaxation. Their T2 MRI performance as contrast agents was confirmed in vivo by measuring T2 MR images in mice before and after intravenous injection.

Efficient photocatalysis-Fenton for degradation of rhodamine B and inhibition of bacteria by core-shell Fe3O4 @UiO-66-NH2 nanospheres

Core-shell Fe3O4 @UiO-66-NH2 nanospheres with superior photocatalytic activity and photo-Fenton performance were synthesized using a layer-by-layer growth strategy. The synthesis involved the use of FeCl3, trisodium citrate, sodium acetate, ZrCl4, and 2-aminoterephthalic acid as raw materials, with mercaptoacetic acid serving as a modifier. Fe3O4 @UiO-66-NH2 demonstrated improved visible-light-driven photocatalytic performance in the oxidation degradation of Rhodamine B (RhB) in the presence of trace amounts of H2O2 under visible light irradiation. The Fe(II)/Fe(III) cycle was accelerated by the transfer of the photogenerated electrons (e-) from UiO-66-NH2 to Fe3O4, which in turn encouraged the Fenton reaction to produce hydroxyl radicals (•OH). With only 10 mmol/L H2O2, the removal rate of RhB approached 94% in 120 min. Furthermore, when exposed to visible light, Fe3O4 @UiO-66-NH2 exhibited 99% efficacious antibacterial activity against Escherichia coli and Staphylococcus aureus. Overall, the as-prepared Fe3O4 @UiO-66-NH2 core-shell nanospheres show promise for practical applications as photocatalysts for the degradation of organic pollutants and the inactivation of bacteria in wastewater.

Mechanistic investigation of mesoporous Mg2+ doped CeO2 encapsulated Fe3O4 core-shells for the selective adsorptive removal of malachite green

Economically viable, easy to operate and highly efficient techniques for water treatment are one of the basic amenities that should be provided to every individual in our society. Here we have developed Fe3O4@Mg2+ doped CeO2 core-shells by a co-precipitation route as magnetically retrievable adsorbents which are highly selective towards hazardous malachite green. The developed core-shell nanostructures were well-characterised using XRD, FE SEM, HR TEM, XPS, BET, VSM and TGA. The developed Fe@CMg-1:2 core-shells exhibited a removal efficiency of 95.1% towards Malachite green. Various parameters affecting the adsorption activity were investigated in detail. The nature, extent and mechanism of the adsorption were evaluated using various adsorption isotherm and kinetic models. Dubinin-Radushkevich (D-R), Freundlich and Temkin adsorption models were used to fit the isotherm data and the maximum adsorption capacity (qm) was found to be 18.44 mg g−1 according to Dubinin-Radushkevich (D-R) model. It was found that the selective adsorption of malachite green over Fe@CMg-1:2 core-shells follows heterogeneous multilayer adsorption which obeys pseudo-second-order kinetics. The developed Fe@CMg-1:2 core-shells also exhibited high thermal stability and reusability. Fe@CMg-1:2 core-shells retained 82.4% removal efficiency even after four successive reusability cycles. Easy separation, high selectivity and cost-effectiveness are the highlights of the developed mesoporous Mg2+ doped CeO2 encapsulated Fe3O4 core-shell structures.

Application of Magnetic Nanocomposites in Water Treatment: Core–Shell Fe3O4 Material for Efficient Adsorption of Cr(VI)

Since ferric tetroxide (Fe3O4) has strong magnetic properties, coating amorphous silica (SiO2) with Fe3O4 nanoparticles can protect the magnetic Fe3O4 particles and form a new magnetic adsorbent with a core–shell structure and small pore size, the strong magnetic properties of which can efficiently solve the problem of the difficult separation and recovery of heavy metals from wastewater affecting present-day adsorption techniques. In this paper, SiO2-coated nanoscale Fe3O4 particles were prepared using a modified sol–gel method for the adsorption and removal of Cr(VI) at lower pollution concentrations. The adsorbent was characterized using Fourier transform infrared spectroscopy (FT-IR), X-ray diffraction (XRD), scanning electron microscopy (SEM), X-ray photoelectron spectroscopy (XPS), and a magnetic vibration sample magnetometer (VSM), and its adsorption performance was systematically investigated in terms of initial concentration, pH, and temperature. The experiments showed that the adsorption effect was optimal when the initial solution Cr(VI) was 40 mg/L. The adsorption capacity increased with a decrease in the initial solution’s pH and decreased with an increase in temperature. Furthermore, the adsorption capacity of Cr(VI) at low concentrations was much higher than that of other conventional adsorbents, the calculated unit adsorption capacity reached 13.609 mg·g−1, and the removal rate reached 64.8%. In addition, the strong magnetic nanocomposite (MS) had excellent recoverability, could achieve desorption via alkaline washing, and retained about 75% of the initial adsorption capacity after six cycles.

Facile Constructing Hierarchical Fe3O4@C Nanocomposites as Anode for Superior Lithium-Ion Storage

Ferroferric oxide (Fe3O4) is regarded to be a promising high-capacity anode material for LIBs. However, the capacity attenuates fast and the rate performance is poor due to the dramatic pulverization and sluggish charge transfer properties. To solve these problems, a simple in situ encapsulation and composite method was successfully developed to construct carbon nanotube/nanorod/nanosheet-supported Fe3O4 nanoparticles. Owing to the hierarchical architecture design, the novel structure Fe3O4@C nanocomposites effectively enhance the charge transfer, alleviate pulverization, avoid the agglomeration of Fe3O4 nanoparticles, and also provide superior kinetics toward lithium storage, thereby showing significantly improved reversibility and rate performance. The carbon nanotube/nanorod supported core-shell structure Fe3O4@C nanocomposite displays outstanding high rate capability and stable cycling performance (reversible capability of 1006, 552 and 423 mA h g−1 at 0.2, 0.5 and 1 A g−1 after running 100, 300 and 500 cycles, respectively).

SO3H-Functionalized Epoxy-Immobilized Fe3O4 Core-Shell Magnetic Nanoparticles as an Efficient, Reusable, and Eco-Friendly Catalyst for the Sustainable and Green Synthesis of Pyran and Pyrrolidinone Derivatives.

A SO3H-functionalized epoxy-immobilized Fe3O4 core-shell magnetic nanocatalyst was prepared through a simple three-step procedure, and it was identified by various analyses such as Fourier transform infrared (FT-IR) spectroscopy, scanning electron microscopy (SEM), differential thermal gravity (DTG), Brunauer-Emmett-Teller (BET) analysis, transmission electron microscopy (TEM), energy-dispersive X-ray spectroscopy (EDX), thermogravimetric analysis (TGA), vibration sample magnetometry (VSM), and powder X-ray diffraction (PXRD). BET analysis showed that the as-prepared nanocatalyst was synthesized with a mesoporous structure and high specific area (35.45 m2 g-1). The TEM image clearly showed that the particle size distribution was in the range of 47-65 nm. The designed magnetic nanocatalyst was used successfully in the synthesis of pyran derivatives via the reaction of dimedone, malononitrile, and various aromatic aldehydes and synthesis of pyrrolidinone derivatives via the reaction of various aromatic aldehydes, aniline, and diethyl acetylenedicarboxylate. The nanocatalyst was simply isolated from the reaction mixture utilizing an external magnet and reused several times according to the model reactions without significant loss in its efficiency.

Fe3O4 Core–Shell Nanostructures with Anticancer and Antibacterial Properties: A Mini-Review

Core–shell nanoparticles are functional materials with tailored properties, able to improve the requirements of various applications. Both core and shell components can be inorganic or organic, and there are numerous studies in this field regarding their synthesis methods, properties, and applications. This review aims to study core–shell nanostructures with Fe3O4 cores and different shell types, observing their antibacterial and anticancer properties. By the type of coating, Fe3O4 core–shell nanoparticles (NPs) are classified into four categories: metal-coated NPs, metal-organic framework (MOF) coated NPs, metal oxide coated NPs, and polymer-coated NPs. Each category is briefly presented, emphasizing anticancer or antibacterial properties and specific applications (cancer diagnosis or therapy, drug carrier). Moreover, synthesis methods and particle size for both core and shell nanostructures, as well as the magnetic properties of the final core–shell material, are summarized in this review. Most of the consulted papers discussed sphere-like core–shell nanoparticles obtained by chemical methods such as coprecipitation, hydrothermal, and green synthesis methods using plant extract. These types of core–shell nanoparticles could be used as drug nanocarriers for tumor-targeted drug delivery, hyperthermia treatment, or contrast agents. Further work needs to be conducted to understand nanoparticles’ interaction with living cells and their traceability in the human body.

Construction of core-shell Fe3O4@MoS2 activates peroxymonosulfate for the degradation of tetracycline: Structure-activity relationship, performance and mechanisms

Peroxymonosulfate (PMS) is an excellent oxidant that can produce multiple radicals. A novel core-shell composite Fe3O4 @MoS2-x (F@M-x) heterostructure was synthesized to degrade tetracycline (TC) by PMS activation. In F@M/PMS catalytic system, more Fe(III) is reduced into Fe(II) by doping MoS2 nanoflowers formed core-shell structure, resulting in the catalytic process being significantly enhanced. Due to the strong complexation tendency of TC towards Fe(II), the Fe(II)-TC complexes* accumulated between the core and shell, which significantly accelerates the PMS activation and TC abatement compared to free Fe(II). The EPR and quenching experimental results revealed that O2•− and 1O2 were detected as the main active species for TC degradation in the F@M/PMS system. Furthermore, the possible TC degradation pathways were proposed and the toxicity estimation of intermediates was evaluated by Toxicity QSAR prediction. These results will be useful for the improvement of PMS-based AOPs activation and expand the application of Fe(II)/PMS systems in the treatment of water containing new organic micro-pollutants.

Improvement of co-frequency synergy between dielectric and magnetic losses of core–shell Fe3O4@C composites for enhancing their microwave absorption properties

Improvement of co-frequency synergy between dielectric and magnetic losses of core–shell Fe3O4@C composites for enhancing their microwave absorption properties

Magnetic dendritic KCC-1 nanosphere-supported cobalt composite as a separable catalyst for hydrogen generation from NaBH4 hydrolysis

The introduction of magnetism into a catalyst can greatly optimize its separation performance. In the present work, a kind of magnetically separable catalysts for promoting NaBH4 hydrolysis have been fabricated by anchoring cobalt nanoparticles on magnetic dendritic KCC-1 nanospheres composed of magnetic Fe3O4 core and fibrous shell. The fabricated catalysts were characterized with various characterization methods, including absorption spectroscopy (AAS), scanning electron microscopy (SEM), high-resolution transmission electronic microscopy (HRTEM), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), vibrating sample magnetometry (VSM), and Fourier transform infrared (FT-IR), etc. This kind of catalysts exhibit high catalytic activity for promoting the hydrolysis of NaBH4 under alkaline conditions, giving a hydrogen generation rate and activation energy of 3.83 L min−1 gCo−1 (30 °C) and 53.63 kJ mol−1, respectively. After used for 5 cycles, the catalyst showed 36.5% catalytic activity reserved. Most importantly, the magnetism of the catalyst made it easily separated and recycled from the solution after the reaction completed. The development of this kind of catalysts could provide a promising option for catalyzing NaBH4 hydrolysis for portable hydrogen production from.

Silver-decorated amino-modified Fe3O4@SiO2@mTiO2 core-shell nanocomposites with catalytic and antimicrobial bifunctional activity

Integrating metal nanocomposites into a matrix is a promising approach for improving the material chemical and physical properties. Herein, Fe3O4 @SiO2 @mTiO2-NH2 @Ag (FSTN-Ag) nanocomposites were synthesized by reducing silver nitrate onto amino-modified double core-shell Fe3O4 @SiO2 @mTiO2-NH2 (FSTN) nanospheres. TEM, XRD, XPS, BET, TOC, UV–vis and FTIR spectrum were used to characterize the nanocomposites. The magnetic FSTN-Ag nanocomposites possessed a core–shell structure, with a specific surface area of 113.6 m2/g, pore volume of 0.122 cm3/g, magnetization saturation of 46.17 emu/g, and Ag mean diameter of 2.8 nm. The FSTN-Ag demonstrated high catalytic activity on reducing methyl orange (MO) and its catalytic ability could kept 85% after 5 cycles. The FSTN-Ag also effectively inhibited S. aureus and E. coli in 20 min by up to 99% or 100%, respectively. It was speculated that the antimicrobial mechanism involved the interaction of Ag+ derived from FSTN-Ag with functional groups of vital enzymes and proteins as well as strong oxidation of reactive oxygen species resulting in bacterial death. In view of the magnetic separation, biocompatibility and recyclability, the FSTN-Ag is expected to become a potential multifunctional material for biomedical and environmental remediation.

Synthesis of uniform Pickering microspheres doped with quantum dot by microfluidic technology and its application in tumor marker

Tumor markers play a significant role in early cancer diagnosis, evaluation of the extent of the disease, and monitoring of therapy response. In this study, we described the Pickering emulsion polymerization method to synthesize uniform magnetic/fluorescent microspheres. A Pickering-structure composed of a lot silica nanoparticle closely covered onto the quantum dot-encoded magnetic microbeads is designed and synthesized. The uniform magnetic/fluorescent microspheres were prepared using a microfluidic device and the performance of the microspheres synthesized by the instruments was evaluated by flow cytometry. To avoid fluorescence quenching and intrinsic toxicity, CdSe/ZnS core-shell quantum dot and Fe3O4 nanoparticle were successfully encapsulated into MFM microspheres using the microfluidic technology. Using this structure enables the facile realization of a theoretical 4 × 4 barcoding matrix combining two colors and four fluorescence intensity levels. Then, different optical codes were prepared by simple changing the emission wavelength and the intensity of the quantum dots. The resulting microsphere are combined with flow cytometer using two lasers for decoding of multiplex tumor markers. Moreover, the stability testing of microspheres demonstrated good performance for further application in detection of tumor markers as well. When applied for the high-throughput ultrasensitive detection of three tumor markers (CEA, CA125 and CA199) in a single sample, the detection limits of 0.027 ng/mL for CEA, 1.48 KU/L for CA125 and 1.09 KU/L for CA199 are achieved, which exhibit superior detection performance. Thus, Pickering-structure magnetic/fluorescent microspheres are promising for application in tumor markers.

Dual-pathway optimization on microwave absorption characteristics of core–shell Fe3O4@C microcapsules: Composition regulation on magnetic core and MoS2 nanosheets growth on carbon shell

Core-shell Fe3O4@C composites with unique configuration and complementary loss mechanisms are widely considered as a kind of prospective functional materials in the field of microwave absorption. However, the balance between core–shell configuration and intrinsic loss is always a thorny problem on the way of good microwave absorption characteristics. Herein, we propose a dual-pathway optimization strategy to consolidate the electromagnetic functions of core–shell Fe3O4@C microcapsules for the first time. On one hand, the chemical composition of magnetic core is finely regulated from Fe3O4 to metal Fe, and it is found that both magnetic loss and dielectric loss can be strengthened effectively through the partial reduction of Fe3O4 core. On the other hand, MoS2 nanosheets are closely anchored on the surface of carbon shell, which can bring more powerful interfacial polarization and dipole polarization to compensate the insufficient dielectric loss caused by the limited thickness and graphitization degree of carbon shell. With the multiple benefits from the dual-pathway optimization strategy, the optimal composite will present good microwave absorption performance, whose effective absorption bandwidth (EAB) and minimum RL value are 5.4 GHz (d = 1.8 mm) and −36.1 dB (5.9 GHz, 4.0 mm), respectively. In particular, its specific EABs (EAB per unit thickness) in different bands are superior to those of most microwave absorbing materials with similar chemical composition. These results demonstrate that this dual-pathway optimization will open a new avenue to enhance microwave absorption performance of core–shell composites in the future.

Curcumin Coated Ultra-Small Iron Oxide Nanoparticles as T1 Contrast Agents for Magnetic Resonance Imaging of Cancer Cells.

The application of nanotechnology in the molecular diagnosis and treatment of cancer is essential. This study aimed to investigate the influence of curcumin-coated ultra-small superparamagnetic iron oxide (USPIO) as a T1 contrast agent in Magnetic Resonance Imaging (MRI). In this experimental study, the influence of curcumin-coated USPIO (Fe3O4@C) on the diagnosis of the cancer cell line was investigated. After synthesis, characterization, and relaxation of Fe3O4@C, the contrast changes in T1-weight MRI to mouse colon carcinoma 26 cell line were evaluated in vitro. Fe3O4@C nanoparticles (NPs) are good at imaging; based on a relaxometry test, the r1 and r2 relaxivities of Dotarem were 3.139 and 0.603 mM-1s-1, respectively. Additionally, the r1 and r2 relaxivities of Fe3O4@C were 3.792 and 1.3 mM-1s-1, respectively, with the rate of 2.155 of r2/r1 NPs. The NPs can be identified as a positive contrast agent with a weight of T1 in MRI. The coresh-ell Fe3O4@C NPs can be effective in cancer treatment and diagnosis because of the therapeutic effects of curcumin and the properties of USPIO.

Core-Shell Fe3O4@C Nanoparticles for the Organic Dye Adsorption and Targeted Magneto-Mechanical Destruction of Ehrlich Ascites Carcinoma Cells.

The morphology, structure, and magnetic properties of Fe3O4 and Fe3O4@C nanoparticles, as well their effectiveness for organic dye adsorption and targeted destruction of carcinoma cells, were studied. The nanoparticles exhibited a high magnetic saturation value (79.4 and 63.8 emu/g, correspondingly) to facilitate magnetic separation. It has been shown that surface properties play a key role in the adsorption process. Both types of organic dyes-cationic (Rhodomine C) and anionic (Congo Red and Eosine)-were well adsorbed by the Fe3O4 nanoparticles' surface, and the adsorption process was described by the polymolecular adsorption model with a maximum adsorption capacity of 58, 22, and 14 mg/g for Congo Red, Eosine, and Rhodomine C, correspondingly. In this case, the kinetic data were described well by the pseudo-first-order model. Carbon-coated particles selectively adsorbed only cationic dyes, and the adsorption process for Methylene Blue was described by the Freundlich model, with a maximum adsorption capacity of 14 mg/g. For the case of Rhodomine C, the adsorption isotherm has a polymolecular character with a maximum adsorption capacity of 34 mg/g. To realize the targeted destruction of the carcinoma cells, the Fe3O4@C nanoparticles were functionalized with aptamers, and an experiment on the Ehrlich ascetic carcinoma cells' destruction was carried out successively using a low-frequency alternating magnetic field. The number of cells destroyed as a result of their interaction with Fe3O4@C nanoparticles in an alternating magnetic field was 27%, compared with the number of naturally dead control cells of 6%.