Manganese ferrite (MnFe2O4) Nanoparticles: From synthesis to application -A review

Simultaneous removal of Cd(II) and Sb(V) by MnFe2O4-biochar composite: Performance and mechanisms

The coexistence of cadmium (Cd) and antimony (Sb) in soils severely threatens environmental safety and human health. While biochar is widely used for soil remediation, its effectiveness in removing multiple metals, especially in the presence of anions, lacks dynamic quantification and mechanistic understanding. This study synthesized a MnFe2O4-biochar composite (MF-RBC) using the coprecipitation method, and explored its adsorption performance and mechanisms for coexisting Cd(II) and Sb(V). The maximum adsorption capacities of MF-RBC for Cd(II) and Sb(V) were 11.24 and 57.33 mg g-1, respectively, higher than those of pure RBC (6.27 mg g-1 for Cd(II), and 19.43 mg g-1 for Sb(V)) and MF (9.25 mg g-1 for Cd(II), and 48.01 mg g-1 for Sb(V). The enhanced performance is attributed to the large specific surface area of MF-RBC (318.86 m2 g-1), improved dispersion of MF particles by biochar, and the attachment of oxygen-containing groups. Additionally, Cd(II) exhibited a synergistic effect on Sb(V) removal, likely due to reduced negative charge repulsion between MF-RBC and Sb(V), and the formation of MF-Cd(II)-Sb(V) ternary complexes. MF-RBC also decreased the availability of Cd and Sb by transforming them into more stable forms. Microscopic and mechanistic analysis revealed that Cd(II) forms complexes with both the CO/CO groups of biochar and the MnO bonds of MnFe2O4, while Sb(V) is primarily complexed with FeO bonds of MnFe2O4 in the Cd&Sb coexistence system. These findings facilitate a better understanding of Cd(II) and Sb(V) behavior in natural environments and offer valuable insights for improving soil remediation strategies.

One-Step Microwave-Assisted Synthesis of MnFe2O4/rGO Nanocomposites and Their Electrochemical Properties in Supercapacitors

In the pursuit of energy conservation and sustainability, supercapacitors offer high power density, fast charge-discharge rates, and long cycle life, making them ideal for applications in electric vehicles and portable electronics. This study presents the synthesis of MnFe2O4/reduced graphene oxide (rGO) nanocomposites through a rapid, one-pot microwave-assisted hydrothermal method. This approach significantly reduces synthesis time relative to conventional hydrothermal techniques. The nanocomposites were structurally characterized using X-ray diffraction (XRD) and Raman spectroscopy, morphologically examined via transmission electron microscopy (TEM) and Brunauer-Emmett-Teller (BET) analysis, and chemically analyzed through Fourier-transform infrared spectroscopy (FT-IR) and thermogravimetric analysis (TGA). Electrochemical testing revealed a high specific capacitance of 196.6 F/g at 0.5 A/g, with 90.22% retention after 6000 cycles at 10 A/g. The superior performance is attributed to the synergistic effects of MnFe2O4 and rGO, enhancing charge storage and stability. These findings demonstrate the potential of microwave hydrothermal synthesis for scalable production of high-performance electrode materials for supercapacitors.

Degradation of Methylene Blue by Ozone Oxidation Catalyzed by the Magnetic MnFe2O4@Co3S4 Nanocomposite

In this study, the MnFe2O4@Co3S4 magnetic nanocomposite was prepared by a two-step hydrothermal method and used to catalyze the ozone oxidation degradation of methylene blue. It was characterized by XRD, EDS, SEM, FT-IR, and XPS. The results showed that the introduction of Co3S4 made MnFe2O4 grow uniformly on Co3S4 nanosheets, which effectively prevented the agglomeration of MnFe2O4. Moreover, MnFe2O4 provided active sites and Mn3+/Mn2+ and Fe3+/Fe2+ cycles for the ozone oxidation process. Not only did Co3S4 provide the active site (Co2+/Co3+) for the ozone oxidation process but also its derived S2-/S22- accelerated the electron transfer rate on the surface of the material, thus improving the efficiency of catalytic ozone oxidation degradation of methylene blue. When the molar ratio of MnFe2O4 to Co3S4 was 6:3 (MnFe2O4@Co3S4-3), the catalytic ozone degradation efficiency of methylene blue was the best, which reached 93.55% in 12 min. The reactive oxygen species in catalytic ozonation degradation of MB were 1O2, O2.-, and ·OH. The MnFe2O4@Co3S4 magnetic nanocomposite is an efficient and stable O3 activator, which maintains high catalytic activity and low metal ion leaching after five cycles, indicating that it has a good application prospect in catalyzing ozone oxidation to degrade organic pollutants.

Manganese ferrite-graphite oxide-chitosan nanocomposite for efficient dye removal from aqueous and textile wastewater under UV and sunlight irradiation

This study presents the development and characterization of manganese ferrite (MnFe2O4)-based nanocomposites with graphite oxide (GO) and chitosan (CS) for efficient dye removal from textile wastewater and aqueous solution. Comprehensive characterization was performed using FT-IR, Raman, XRD, BET, SEM, DRS and Zeta potential techniques. XRD analysis confirmed the cubic spinel structure of MnFe2O4, with characteristic peaks at 2θ = 32, 35, 48, 53, 62, and 64°. BET analysis revealed a high specific surface area of 442.57 m2/g and a pore diameter of 2.36 nm for the MnFe2O4/GO/CS nanocomposite. SEM imaging showed polyhedral MnFe2O4 particles (11-33 nm) deposited on a wrinkled graphite oxide matrix. DRS analysis indicated band gap energies of 3.1 eV for MnFe2O4, 3.0 eV for MnFe2O4/GO, and 3.5 eV for MnFe2O4/GO/CS. Zeta potential measurements showed a positive surface charge (+ 36.8 mV) for MnFe2O4/GO/CS. The MnFe2O4/GO/CS nanocomposite exhibited exceptional photocatalytic performance under UV light irradiation. It achieved 99.9 and 99.5% removal of Reactive Red 198 dye and Brilliant Blue FCF 133, respectively. The photocatalytic process followed pseudo-second-order kinetics (R2 = 0.99). In real textile wastewater treatment, the nanocomposite reduced BOD from 889 to 0.86 mg/L and COD from 1227 to 74 mg/L, with 96% dye removal. Also, MnFe2O4/GO/CS showed excellent performance under sunlight irradiation and maintained high removal efficiencies over multiple cycles, demonstrating good reusability. This study highlights the potential of the MnFe2O4-based nanocomposites as versatile and sustainable solutions for remediating dye-contaminated water.

MnFe2O4-loaded bamboo pulp carbon-based aerogel composite: synthesis, characterization and adsorption behavior study for heavy metals removal

Heavy metal wastewater is a direct threat to the ecological environment and human health because it is highly toxic at low concentrations. Therefore, it is very important to explore and develop efficient wastewater treatment agents. MnFe2O4-loaded bamboo pulp carbon-based aerogel (MCA) is prepared by directional freeze-drying and carbonization. SEM, TEM, XPS, XRD, BET and FTIR are used to evaluate the physical and chemical properties of MCA. Meanwhile, the adsorption performances of MCA on Pb2+, Cu2+ and Cd2+ are also studied by adsorption kinetics, isothermal curves and thermodynamics. The results show that the adsorption process involves chemical adsorption and physical adsorption, and the adsorption process is a spontaneous endothermic process. The maximum adsorption capacities of MCA for Pb2+, Cu2+ and Cd2+ obtained in the adsorption isotherm experiments were 74.38, 84.21 and 73.63 mg g-1, respectively, showing excellent adsorption performance for Pb2+, Cu2+ and Cd2+. Therefore, the MCA has potential application for wastewater purification of heavy metals containing Pb2+, Cu2+ and Cd2+, meanwhile, this study provides some guidance for the design and application of microspheres for the separation and removal of Pb2+, Cu2+ and Cd2+.

The recent advances of MnFe2O4-based nanoparticles in environmental application: A review

The manganese ferrite (MnFe2O4)-based nanoparticles showed a substantial potential to remediate the various pollutants in environmental application due to low cost, simple magnetic separation and high removal capacity. Herein, the functionalization of various MnFe2O4-based nanoparticles was briefly summarized; Then the recent advances concerning the removal of pollutants (i.e., organics, heavy metals and antibacterial activity) on different MnFe2O4-based nanoparticles were reviewed in details. The reactivity of MnFe2O4-based nanoparticles was significantly influenced by environmental factors. It is demonstrated that interaction mechanism of various pollutants on magnetic MnFe2O4-based nanoparticles included degradation, adsorption, coordination, redox and precipitation. Finally, the current problems and future perspective of MnFe2O4-based nanoparticles were proposed. The highlight of this review is to compare the removal performance of MnFe2O4-based nanoparticles with the different hybrids. This review is crucial for the application of MnFe2O4-based nanoparticles in the environmental remediation.

Manganese Oxide Nanoparticles for MRI-Based Multimodal Imaging and Theranostics

Manganese-based MRI contrast agents have recently attracted much attention as an alternative to Gd-based compounds. Various nanostructures have been proposed for potential applications in in vivo diagnostics and theranostics. This review is focused on the discussion of different types of Mn oxide-based nanoparticles (MnxOy NPs) obtained at the +2, +3 and +4 oxidation states for MRI, multimodal imaging or theranostic applications. These NPs show favorable magnetic properties, good biocompatibility, and an improved toxicity profile relative to Gd(III)-based nanosystems, showing that the Mn paramagnetic ions offer advantages for the next generation of nanoscale MRI and theranostic contrast agents. Their potential for enhancing relaxivity and MRI contrast effects is illustrated through discussion of selected examples published in the past decade.

Revolutionizing microorganism inactivation: Magnetic nanomaterials in sustainable photocatalytic disinfection

The rapid emergence of antibiotic-resistant microorganisms and the demand for sustainable water purification methods have spurred research into advanced disinfection, with photocatalysis as a promising approach. This study explores magnetic nanomaterials as catalysts in photocatalytic processes for microorganism inactivation. Magnetic nanoparticles and composites, due to their unique properties, are promising for enhancing photocatalytic disinfection. Their inherent magnetic traits enable easy separation and recyclability, reducing operational costs and environmental impact. These materials also act as efficient electron transfer mediators, enhancing overall photocatalytic efficiency. The review covers the synthesis and characterization of magnetic nanomaterials for photocatalytic applications, focusing on their structural, magnetic, and surface properties. Photocatalytic mechanisms, including reactive oxygen species (ROS) generation vital for microorganism inactivation, are discussed. The study examines combining common photocatalysts like TiO2, ZnO, and semiconductors with magnetic nanomaterials, highlighting synergistic effects. Recent advances and challenges, such as optimal nanomaterials selection and scalability for large-scale applications, are addressed. Case studies and experimental setups for microorganism inactivation underscore the potential of magnetic nanomaterials in water treatment, air purification, and medical disinfection. Finally, further research directions and research highlights the substantial potential of magnetic nanomaterials as catalysts in photocatalytic processes, offering an efficient and sustainable solution for microorganism inactivation and contributing valuable insights to environmental and public health advancement.

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

BACKGROUND

Superparamagnetic properties and excitation independence have been incorporated into carbon-decorated manganese ferrite nanodots (MnFe@C) to introduce an economical and safer multimodal agent for use in both T1-T2 MRI and fluorescence-based imaging to replace the conventional highly toxic heavy metal contrast agents.

METHODS

The surface conjugation of 8-anilino-1-naphthalenesulfonate (ANS) to MnFe@C nanodots (ANS-MnFe@C) enhances both longitudinal and transverse MRI relaxation, improves fluorescence for optical imaging, and increases protein detection sensitivity, showing higher multimodal efficacy in terms of molar relaxivity, radiant efficiencies, and fluorescence sensitivity compared to MnFe@C.

RESULTS

The band gap energy was determined using Tauc's equation to be 3.32 eV, while a 72% quantum yield demonstrated that ANS-MnFe@C was highly fluorescent, with the linear range and association constant calculated using the Stern-Volmer relation. The synthesized ANS-MnFe@C demonstrated excellent selectivity and sensitivity for bovine serum albumin (BSA), with a nanomolar detection limit of 367.09 nM and a broad linear range from 0.015 to 0.225 mM.

CONCLUSIONS

In conclusion, ANS-MnFe@C holds ease of fabrication, good biocompatibility, as assessed in A375 cells, and an effective pH-sensitive doxorubicin release profile to establish anticancer activity in lung cancer cell line (A549), highlighting its potential as an affordable therapeutic agent for multimodal imaging, drug delivery, and protein sensing.

Removal of Sulfamethoxazole Using Fe-Mn Biochar Filtration Columns: Influence of Co-existing Polystyrene Microplastics

Emerging contaminants, particularly antibiotics and microplastics (MPs), present significant challenges in wastewater treatment and pose large ecological risks. This study investigates the removal efficiency of sulfamethoxazole (SMX) using Fe-Mn modified biochar (BFM) in fixed bed filtration columns, emphasizing the effect of the presence of polystyrene microplastics (PS-MPs) on SMX behavior in both water (pH≈5.6) and selected wastewater (pH≈8) systems. Batch sorption results show that 10 mg/L SMX in 50 mL water can be completely removed by 100 mg BFM sorbent. The Bed Depth Service Time model indicated the BFM column is feasible for SMX removal in scaled-up continuous wastewater flow operations, while the Yan model best elucidates SMX filtration behavior and suggests the dominant adsorption mechanisms include external mass transfer and intraparticle diffusion. The present of both 20 mg/L and 100 mg/L PS-MPs (pH≈5.6) significantly reduced SMX retention due to competitive sorption. However, at pH 3.2, competitive sorption became negligible due to electrostatic interactions driving the PS-MPs sorption, while neutral charged SMX bound through hydrogen-bonds or π-π EDA interactions. Elevated pH shifted both PS-MPs and SMX sorption to non-electrostatic thus intensifying sorption competition, highlighting the influence of pH on their interaction dynamics. In wastewater, SMX filtration was slightly inhibited by 100 mg/L PS-MPs in BFM columns, whereas PS-MPs removal remained unaffected due to the high ionic strength and alkaline pH. These findings highlight the impact of MPs on pollution removal efficiency in filtration system, essential for enhancing biochar-based wastewater treatment strategies.

Role of metal oxide ferrites in the process of magnetic hyperthermia - A review

Extensive research has been conducted on the manufacturing of nano ferrites, and their use in magnetic hyperthermia therapy has shown promising results in cancer treatment. This study aims primarily to provide an overview of the latest developments in the synthesis of magnetic nanoparticles (MNPs) for the treatment of hyperthermia. Magnetic nanoparticles are biocompatible and have a stable magnetic state, nano ferrites have become recognized as apex thermoseeds in biomedical applications, specifically for the treatment of magnetic hyperthermia. Employing dopant materials, biocompatible overlay, and preparation techniques, one may study the effectiveness of nano ferrites. Furthermore, specific requirements need to be met for using nano ferrites in cancer treatments like magnetic hyperthermia. These include low toxicity, biocompatibility, a higher specific absorption rate, a shorter time to reach the targeted hyperthermia temperature, crystalline size within the biological radius, and a lower dose of the nano ferrite. A potential resolution involves identifying the limitations and proposing enhanced nanocomposite materials that amplify their magnetic characteristics via a biocompatible overlay, all while optimizing the effectiveness and functioning of magnetic nanoferrites. To increase the effectiveness of ferrite nanoparticles in treating hyperthermia, this study will figure out their constraints and offer solutions for more effective ferrite-based nanocomposites that may prove to be a viable therapy option for cancer in the future.

Recent developments in the bio-mediated synthesis of CoFe2O4 nanoparticles using plant extracts for environmental and biomedical applications

Conventional methods for the synthesis of nanoparticles often involve toxic chemicals, exacerbating environmental issues in the context of climate change and water scarcity. Green synthesis using plant extracts offers a sustainable and viable alternative for CoFe2O4 nanoparticle production, but understanding the mechanisms and applications of this method is challenging. Here, we review the synthesis and applications of CoFe2O4 nanoparticles using plant extracts with emphasis on biomedical activity and water treatment. Plant extract-mediated CoFe2O4 nanoparticles exhibit high surface area, small particle size, unique morphology, sufficient band gap energy, and high saturation magnetization. These nanoparticles demonstrate strong antimicrobial and anticancer activities, highlighting their potential in biomedical treatments. Green CoFe2O4 are effective in removing organic dyes, heavy metals, and pharmaceuticals from water, promoting cleaner water resources. Challenges such as scalability and reproducibility still remain, but ongoing research aims to optimize synthesis protocols and explore new applications. This work underscores the importance of sustainable nanotechnology in addressing environmental challenges.

Improvement of photocatalytic ammonia production of cobalt ferrite nanoparticles utilizing microporous ZSM-5 type ferrisilicate zeolite

The development of decarbonized synthesis approaches is a critical step in the fabrication of ammonia, an indispensable chemical and a potential carbon-neutral energy carrier. In this regard, the photocatalytic production technology has gained ample attention as a sustainable alternative to energy-intensive and environmentally detrimental Haber-Bosch process. Here, we present cobalt ferrite nanoparticles supported on microporous ZSM-5 type ferrisilicate zeolite as a desirable novel photocatalyst for the ammonia generation. The zeolite introduced as a microporous support increasing the catalytically active sites. A straightforward one-pot sol-gel method was used to synthesize cobalt ferrite (CoFe2O4) and CoFe2O4/ferrisilicate (CF/FS) nanocomposites with various weight percentages (10, 25 and 50%) of CoFe2O4. The photocatalytic performances of the samples in the production of ammonia were investigated under visible light irradiation. The highest rate of NH4+ production (484.74 µmol L-1 h-1) was achieved using the CF50%/FS photocatalyst. The distribution of < 50 nm-sized CoFe2O4 nanoparticles on the surface of the zeolite, as demonstrated by TEM images, and extensive BET surface areas are presented as convincing evidences for the improved photocatalytic activity paticularly in CF50%/FS photocatalyst.

Green synthesis of manganese ferrite magnetic nanoparticle and its modification with metallic-organic frameworks for the tetracycline adsorption from aqueous solutions: A mathematical study of kinetics, isotherms, and thermodynamics

In the current investigation, MnFe2O4/ZIF-8 nanocomposite was generated as a magnetic nanoadsorber using the extract of Dracocephalum plant and characterized by XRD, FTIR, VSM, BET, FESEM, EDS-mapping, TEM, XPS, TPD-NH3, and TGA analyses. Also, to determine its efficiency in the adsorption process of tetracycline, the effect of pH (3-9), nanocomposite dose (0.025-2 g/L), initial pollutant concentration (5-100 mg/L), contact time (5-200 min), and temperature (5-50 °C) were studied. The results of the morphological properties of the magnetic nanocomposite confirmed the spherical shape of this nanoadsorber with an average size of 54 ± 31 nm. BET analysis showed that modification of MnFe2O4 material with ZIF-8 as a new nanoadsorber leads to excellent modification of SBET (143.8 m2/g) and VTotal (0.44 cm3/g). The highest removal efficiency of tetracycline in optimal conditions (pH = 7, contact time = 120 min, nanocomposite dose = 1.5 g/L, and temperature = 20 °C for a tetracycline concentration of 20 mg/L) was 90.11%. As the temperature increased, the removal efficiency increased from 40.46% to 95.06% during 120 min, which indicates that the adsorption reaction is endothermic. In addition, the data obtained from the isotherms of Langmuir (R2 = 0.958), Freundlich (R2 = 0.534), and Temkin (R2 = 0.747) showed that the tetracycline adsorption is monolayer and on the homogeneous surface of the synthesized magnetic nanoadsorber. The elimination process of tetracycline by nanoadsorber followed the pseudo-second order model (R2 = 0.998). Investigating the effect of interfering ions also confirmed the decrease in the adsorption efficiency. Also, the investigation of the reusability of the synthesized magnetic nanoadsorber in tetracycline adsorption indicates that after eight cycles, the efficiency decreases by %16.51. According to the results, the magnetic nanocomposite synthesized in this work can be a suitable and economical adsorber for the removal of tetracycline from aqueous environments.

Shining light on environmental remediation: a type-II heterojunction MnFe2O4/rGO nanocomposites for enhanced photocatalytic degradation of organic dyes and bisphenol A

In this study, the pressing issue of persistent organic pollutants in wastewater was addressed by designing and fabricating a magnetically separable MnFe2O4/rGO heterostructure catalyst for efficient mineralization of bisphenol A (BPA) and dyes such as alizarin red S (anionic) and malachite green (cationic), which are known for their resistance to biodegradation and carcinogenic properties. Comprehensive structural and surface analyses using XRD, XPS, SEM, and TEM/HRTEM coupled with magnetic and optical property measurements revealed the formation of the MnFe2O4/rGO heterostructures. Among all, the MnFe2O4/rGO-10 catalyst with 10% wt% of rGO exhibited 100% efficiency in the mineralization of BPA and both dyes under visible light illumination within 60 min. The stability and recyclability of the catalyst, assessed through XRD and VSM studies, demonstrated its consistent performance over multiple uses. The cost-effectiveness and stability of this catalyst underscore its potential for practical application in wastewater treatment, offering a viable solution to the persistent challenge of removing stubborn organic contaminants.

Enhancement of dielectric permittivity and Havriliak-Negami relaxation mechanism in MnFe2O4through Dy substitution

Pristine and Dy substituted MnFe2O4,MnFe2-xDyxO4(x= 0.00, 0.02, 0.04, 0.06, 0.08 & 0.10) were successfully synthesized by sol-gel method to investigate the dielectric properties of the system. MnFe2O4exhibits a high dielectric permittivity of order 104which is further augmented by 60% through Dy substitution. This is owing to the rise in interfacial polarization resulting from localized states, dipolar polarization arising from the multiple valence states of Fe and Mn ions, atomic polarization due to structural distortion induced by strain, and electronic polarization stemming from the concentration of free charge carriers. The enhancement of induced strain, mixed valence ratio of Fe2+/Fe3+and Mn4+/Mn2+, localized states, and free charge carrier concentration are confirmed from the XRD, XPS, and optical studies, respectively. The dielectric relaxation mechanism of MnFe2-xDyxO4follows a modified Havriliak-Negami relaxation model with conductivity contribution. Complex impedance analyses further validate the contribution of grain-grain boundary mechanisms to the dielectric properties confirmed through Nyquist plots. A comprehensive analysis of conductivity reveals the significant impact of Dy substitution on the electrical conductivity of MnFe2O4. This influence is strongly related to the variations in the concentration of free charge carriers within the MnFe2-xDyxO4system. The understanding of the underlying physics governing the dielectric properties of Dy-substituted MnFe2O4not only enhances the fundamental knowledge of material behavior but also opens new avenues for the design and optimization of advanced electronic and communication devices.

Magnetic Nanoparticles: A Comprehensive Review from Synthesis to Biomedical Frontiers

Nanotechnology has opened new doors of exploration, particularly in materials science and healthcare. Magnetic nanoparticles (MNP), the tiny magnets, because of their various properties, have the potential to bring about radical changes in the field of medicine. The distinctive surface chemistry, nontoxicity, biocompatibility, and, in particular, the inducible magnetic moment of magnetic materials has attracted a great deal of interest in morphological structures from a variety of scientific domains. This review presents a concise overview of MNPs and their crucial properties and synthesis routes. It also aims to highlight the continuous synthesis methods available for MNP production. In recent years, the use of computational methods for understanding the behavior of nanoparticles has been on the rise. Thus, we also discuss the numerical models developed to understand how magnetic nanoparticles can be used in magnetic hyperthermia and targeting the Circle of Wilis. With the increasing use of MNPs in biomedical applications, it becomes necessary to understand the mechanisms of toxicity, which are elucidated in this review. The review focuses on the biomedical applications of MNPs in drug delivery, theranostics, and MRI contrasting agents. We anticipate that this article will broaden the perspective on magnetic nanoparticles and help to understand their functionality and applicability better.

Magnetic hyperthermia in cancer therapy, mechanisms, and recent advances: A review

Hyperthermia therapy refers to the elevating of a region in the body for therapeutic purposes. Different techniques have been applied for hyperthermia therapy including laser, microwave, radiofrequency, ultrasonic, and magnetic nanoparticles and the latter have received great attention in recent years. Magnetic hyperthermia in cancer therapy aims to increase the temperature of the body tissue by locally delivering heat from the magnetic nanoparticles to cancer cells with the aid of an external alternating magnetic field to kill the cancerous cells or prevent their further growth. This review introduces magnetic hyperthermia with magnetic nanoparticles. It includes the mechanism of the operation and magnetism behind the magnetic hyperthermia phenomenon. Different synthesis methods and surface modification to enhance the biocompatibility, water solubility, and stability of the nanoparticles in physiological environments have been discussed. Recent research on versatile types of magnetic nanoparticles with their ability to increase the local temperature has been addressed.

MnFe2O4/MoS2 catalyst used for ozonation: optimization and mechanism analysis of phenolic wastewater treatment

The performance of catalytic ability of MFe2O4/MoS2 in the ozonation process was investigated in this work. The synthesized MnFe2O4/MoS2 was optimize prepared and then characterized by scanning electron microscopy, transmission electron microscopy, X-ray diffraction, X-ray photo-electron spectroscopy, and magnetic saturation strength. The results showed that when Cphenol = 200 mg/L, initial pH = 9.0, Q = 0.10 L/min, and CMnFe2O4/MoS2 = 0.10 g/L, MnFe2O4/MoS2 addition improved the degradation efficiency of phenol by 20.0%. The effects of pH, catalyst dosage, and inorganic ions on the phenol removal by the MnFe2O4/MoS2 catalytic ozonation were investigated. Five cycle experiments proved that MnFe2O4/MoS2 had good recyclability and stability. MnFe2O4/MoS2 also showed good catalytic performance in the treatment of coal chemical wastewater pesticide wastewater. The MnFe2O4 doped with MoS2 could provide abundant surface active sites for ozone and promote the stable cycle of Mn2+/Mn3+and Fe2+/Fe3+, thus generating large amounts of •OH and improving the degradation of phenol by ozonation. The MnFe2O4/MoS2/ozonation treatment system provides a technical reference and theoretical basis for industrial wastewater treatment.

Biocompatible gelatin-coated ferrite nanoparticles: A magnetic approach to advanced drug delivery

Nanotechnology has transformed drug delivery, offering opportunities to enhance treatment outcomes while minimizing adverse effects. This study focuses on gelatin-coated cobalt and manganese ferrite nanoparticles for potential drug delivery applications. The synthesis involved a co-precipitation method, and the nanoparticles were characterized using various techniques, including X-ray diffraction (XRD), scanning electron microscopy (SEM), Fourier-transform infrared spectroscopy (FTIR), Raman spectroscopy, and vibrating sample magnetometer (VSM). Results revealed stable structures, distinct chemical features introduced by gelatin coating, and unique magnetic properties. The hemolysis assay demonstrated reduced hemolytic activity with gelatin coating, enhancing biocompatibility. Drug release studies indicated differential release profiles, with gelatin-coated cobalt ferrite exhibiting higher drug release compared to gelatin-coated manganese ferrite. The Higuchi model supported diffusion-controlled drug release for gelatin-coated cobalt ferrite. These findings suggest the potential of gelatin-coated ferrite nanoparticles for controlled and targeted drug delivery, highlighting their significance in advancing nanomedicine.

Nanotechnology in Agriculture: Manganese Ferrite Nanoparticles as a Micronutrient Fertilizer for Wheat

Limited research has focused on nanoparticle (NP) applications' impact on edible wheat parts in a field environment. Here, we studied the nutritional quality of edible parts of wheat (Triticum aestivum L.) with a field experiment by spraying MnFe2O4 nanoparticles. Wheat was foliar sprayed with 0, 25, 50, and 100 mg/L composite manganese ferrite (MnFe2O4) NPs during 220 d of a growth period. Ionic controls were prepared using the conventional counterparts (MnSO4·H2O and FeSO4·7H2O) to compare with the 100 mg/L MnFe2O4 NPs. After three consecutive foliar applications, nanoparticles demonstrated a substantial elevation in grain yield and harvest index, exhibiting a noteworthy increase to 5.0 ± 0.12 t/ha and 0.46 ± 0.001 in the 100 mg/L NP dose, respectively, concomitant with a 14% enhancement in the grain number per spike. Fe, Mn, and Ca content in grain increased to 77 ± 2.7 mg/kg, 119 ± 2.8 mg/kg, and 0.32 ± 7.9 g/kg in the 100 mg/L NPs, respectively. Compared to the ion treatment, the 100 mg/L NP treatments notably boosts wheat grain crude protein content (from 13 ± 0.79% to 15 ± 0.58%) and effectively lowers PA/Fe levels (from 11 ± 0.7 to 9.3 ± 0.5), thereby improving Fe bioavailability. The VSM results exhibited a slight superparamagnetic behavior, whereas the grains and stems exhibited diamagnetic behavior. The results indicate that the nanomaterial did not accumulate in the grains, suggesting its suitability as an Fe and Mn-rich fertilizer in agriculture. Above all, the foliar application of nanocomposites increased the concentrations of Fe, Mn, and Ca in wheat grains, accompanied by a significant enhancement in grain yield. Therefore, the research results indicate that the foliar application of MnFe2O4 NPs can positively regulate wheat grains' nutritional quality and yield.

Development of natural attapulgite derived ferromanganese spinel oxides as heterogeneous catalysts for persulfate activation of tetracycline degradation

Ferromanganese spinel oxides (MnFe2O4, MFO) have been proven effective in activating persulfate for pollutants removal. However, their inherent high surface energy often leads to agglomeration, diminishing active sites and consequently restricting catalytic performance. In this study, using Al-MCM-41 (MCM) mesoporous molecular sieves derived from natural attapulgite as a support, the MFO/MCM composite was synthesized through dispersing MnFe2O4 nanoparticles on MCM carrier by a simple hydrothermal method, which can effectively activate persulfate (PS) to degrade Tetracycline (TC). The addition of Al-MCM-41 can effectively improve the specific surface area and adsorption performance of MnFe2O4, but also reduce the leaching amount of metal ions. The MFO/MCM composite exhibited superior catalytic reactivity towards PS and 84.3% removal efficiency and 64.7% mineralization efficiency of TC (20 mg/L) was achieved in 90 min under optimized conditions of 0.05 mg/L catalyst dosage, 5 mM PS concentration, room temperature and no adjustment of initial pH. The effects of various stoichiometric MFO/MCM ratio, catalyst dosage, PS concentration, initial pH value and co-existing ions on the catalytic performance were investigated in detail. Moreover, the possible reaction mechanism in MFO-MCM/PS system was proposed based on the results of quenching tests, electron paramagnetic resonance (EPR) and XPS analyses. Finally, major degradation intermediates of TC were detected by liquid chromatography mass spectrometry technologies (LC-MS) and four possible degradation pathways were proposed. This study enhances the design approach for developing highly efficient, environmentally friendly and low-cost catalysts for the advanced treatment process of antibiotic wastewater.

Magnetic hydrogel applications in articular cartilage tissue engineering

Articular cartilage defects afflict millions of individuals worldwide, presenting a significant challenge due to the tissue's limited self-repair capability and anisotropic nature. Hydrogel-based biomaterials have emerged as promising candidates for scaffold production in artificial cartilage construction, owing to their water-rich composition, biocompatibility, and tunable properties. Nevertheless, conventional hydrogels typically lack the anisotropic structure inherent to natural cartilage, impeding their clinical and preclinical applications. Recent advancements in tissue engineering (TE) have introduced magnetically responsive hydrogels, a type of intelligent hydrogel that can be remotely controlled using an external magnetic field. These innovative materials offer a means to create the desired anisotropic architecture required for successful cartilage TE. In this review, we first explore conventional techniques employed for cartilage repair and subsequently delve into recent breakthroughs in the application and utilization of magnetic hydrogels across various aspects of articular cartilage TE.

Nanoparticle Polymers Influence on Cardiac Health: Good or Bad for Cardiac Physiology?

Cardiovascular diseases (CVD) are one of the leading causes of death and morbidity worldwide. Lifestyle modifications, medications, and addressing epidemiological factors have long been at the forefront of targeting therapeutics for CVD. Treatments can be further complicated given the intersection of gender, age, unique comorbidities, and healthcare access, among many other factors. Therefore, expanding treatment and diagnostic modalities for CVD is absolutely necessary. Nanoparticles and nanomaterials are increasingly being used as therapeutic and diagnostic modalities in various disciplines of biomedicine. Nanoparticles have multiple ways of interacting with the cardiovascular system. Some of them alter cardiac physiology by impacting ion channels, whereas others influence ions directly or indirectly, improving cellular death via decreasing oxidative stress.  While embedding nanoparticles into therapeutics can help enhance healthy cardiovascular function in other scenarios, they can also impair physiology by increasing reactive oxidative species and leading to cardiotoxicity. This review explores different types of nanoparticles, their effects, and the applicable dosages to create a better foundation for understanding the current research findings.

Adsorption Behavior of Organoarsenicals over MnFe2O4-Graphene Hybrid Nanocomposite: The Role of Organoarsenic Chemical Structures

As a kind of emerging contaminant, organoarsenic compounds have drawn wide concern because of their considerable solubilities in water, and the highly toxic inorganic arsenic species formed during their biotic and abiotic degradation in the natural environment. Thus, the effective removal and studying of the adsorption mechanism of organoarsenic compounds are of significant urgency. In this work, MnFe2O4 and MnFe2O4/graphene were prepared through a facile solvothermal method. From the results of the Transmission Electron Microscope (TEM) characterization, it can be found that MnFe2O4 nanoparticles were uniformly distributed on the surface of the graphene. And the specific surface area of the MnFe2O4/graphene was about 146.39 m2 g-1, much higher than that of the MnFe2O4 (86.15 m2 g-1). The interactions between organoarsenic compounds and adsorbents were conducted to study their adsorption behavior and mechanism. The maximum adsorption capacities of MnFe2O4/graphene towards p-arsanilic acid (p-ASA) and roxarsone (ROX) were calculated to be 22.75 and 30.59 mg g-1. Additionally, the ionic strength, negative ions, and humus were introduced to investigate the adsorption performance of organoarsenic compounds. Electrostatic adsorption and surface complexation are the primary adsorption mechanisms on account of X-ray photoelectron spectroscopy (XPS) and the Fourier-transform infrared spectroscopy (FT-IR) analysis. This research extends the knowledge into studying the interaction between organoarsenic species and hybrid nanomaterials in the natural environment.

Synthesis and characterization of Pd0 nanoparticles supported over hydroxyapatite nanospheres for potential application as a promising catalyst for nitrophenol reduction

Nitrophenols, which are defined as an important toxic and carcinogenic pollutant in agricultural and industrial wastewater due to their solubility in water, form of resistance against all organisms in water resources. It is vital that these compounds, which are highly toxic as well as highly explosive, are removed from the aquatic ecosystem. In this paper, we reported the preparation and advanced characterization of Pd0 nanoparticles supported over hydroxyapatite nanospheres (Pd0@nano-HAp). The catalytic efficiency of the Pd0@nano-HAp catalyst was examined in the reduction of nitrophenols in water in the presence of NaBH4 as reducing agent and the great activity of catalyst have been specified against 2-nitrophenol, 4-nitrophenol, 2,4-dinitrophenol and 2,4,6-trinitrophenol compounds with 70.6, 82.4, 27.6 and 41.4 min-1 TOFinitial values, respectively. Another important point is that the Pd0@nano-HAp catalyst has perfect reusability performance (at 5th reuse between 68.5 and 92.8 %) for the reduction of nitrophenols. In addition, catalytic studies were carried out at different temperatures in order to determine thermodynamic parameters such as Ea, ΔH≠ and ΔS≠.

Influence of Ru doping on structural, optical, and photocatalytic properties of (Cd-Ni-Mn) nanoferrites

This study reports the synthesis of (Cd0.4Ni0.4Mn0.2)Fe2-xRuxO4 nanoparticles (NPs), where x = 0.00, 0.005, 0.01, 0.015, 0.02, and 0.04, via co-precipitation method. The synthesized samples were characterized by X-ray diffraction (XRD), transmission electron microscope (TEM), and photoluminescence (PL) spectroscopy. The results confirmed the purity of the samples with the presence of a very small fraction of the hematite phase. Pseudo-spherical morphology was recognized from TEM images. Then, the prepared samples were further used as effective photocatalysts for the degradation of nitrobenzene under UV irradiation to examine the effect of doping on the photocatalytic activity. Among the synthesized samples, (Cd0.4Ni0.4Mn0.2)Fe1.985Ru0.015O4 NPs exhibited superior photocatalytic activity. This result is in good agreement with photoluminescence (PL) analysis in which (Cd0.4Ni0.4Mn0.2)Fe1.985Ru0.015O4 NPs revealed the slowest recombination rate of the electron-hole pair. To further improve the photocatalytic performance, different weight % of graphene was incorporated with (Cd0.4Ni0.4Mn0.2)Fe1.985Ru0.015O4 NPs. Finally, 81.41% of nitrobenzene was degraded after 180 min in the presence of 5 wt% graphene/(Cd0.4Ni0.4Mn0.2)Fe1.985Ru0.015O4 nanocomposites, and the degradation rate constant was estimated as 8.4 × 10-3 min-1.

Ultrasonic irradiation-assisted MnFe2O4 nanoparticles catalyzed solvent-free selective oxidation of benzyl alcohol to benzaldehyde at room temperature

Magnetic nanoparticles (NPs) play a vital role in heterogeneous catalysis because of their easy separation, and effective recyclability. Herein, we report the synthesis of MnFe2O4 NPs for use as catalysts in the selective oxidation of benzyl alcohol to benzaldehyde under mild conditions. The MnFe2O4 NPs have been synthesized by precipitation method followed by hydrothermal ageing at 180 °C for 4.0 h. We have investigated the effect of chitosan and carboxymethyl cellulose on the size or morphology of the formed MnFe2O4 NPs. The X-ray diffraction study confirms the formation of pure and crystalline MnFe2O4 with varying average crystallite sizes ranging from 18 to 28 nm based on the type of additive used. The electron microscopy study reveals that the additive plays a significant role in controlling the morphology of the formed MnFe2O4 NPs. These MnFe2O4 NPs exhibit superparamagnetic behaviour at room temperature and can effectively catalyze the solvent-free selective oxidation of benzyl alcohol to benzaldehyde in the presence of tert-butyl hydroperoxide at room temperature under ultrasonic irradiation. The developed protocol can be extended to various substituted benzyl alcohols having both the electron withdrawing and electron donating groups to afford moderate to excellent yield of the products. The catalyst is magnetically retrievable, highly stable, and can be reused up to the sixth run without significant loss of catalytic activity.

Spinel ferrite nanoparticles as potential materials in chlorophenol removal from wastewater

Persistent organic pollutants (POPs) including chlorophenols (CPs) are increasing in water effluents, creating serious problems for both aquatic and terrestrial lives. Several research attempts have considered the removal of CPs by functionalised nanomaterials as adsorbents and catalysts. Besides the unique crystal structure, spinel ferrite nanomaterials (SFNs) own interesting optical and magnetic properties that give them the potential to be utilised in the removal of different types of CPs. In this review, we highlighted the recent research work that focused on the application of SFNs in the removal of different CP substances based on the number of chlorine atom attached to the phenolic compound. We have also discussed the structure and properties of SFN along with their numerous characterisation tools. We demonstrated the importance of identifying the structure, surface area, porosity, optical properties, etc. in the efficiency of the SFN during the CP removal process. The reviewed research efforts applied photocatalysis, wet peroxide oxidation (WPO), persulfate activated oxidation and adsorption. The studies presented different paths of enhancing the SFN ability to remove the CPs including doping (ion substitution), oxide composite structure and polymer composite structure. Experimental parameters such as temperature, dosage of CPs and SFN structure have shown to have a major effect in the CP removal efficiency. More attention is needed to investigate the different properties of SFN that can be tailored through different techniques and expected to have major role in the removal mechanism of CPs.

Novel Biocompatible Magnetoelectric MnFe2 O4 Core@BCZT Shell Nano-Hetero-Structures with Efficient Catalytic Performance

Magnetoelectric (ME) small-scale robotic devices attract great interest from the scientific community due to their unique properties for biomedical applications. Here, novel ME nano hetero-structures based on the biocompatible magnetostrictive MnFe2 O4 (MFO) and ferroelectric Ba0.85 Ca0.15 Zr0.1 Ti0.9 O3 (BCZT) are developed solely via the hydrothermal method for the first time. An increase in the temperature and duration of the hydrothermal synthesis results in increasing the size, improving the purity, and inducing morphology changes of MFO nanoparticles (NPs). A successful formation of a thin epitaxial BCZT-shell with a 2-5 nm thickness is confirmed on the MFO NPs (77 ± 14 nm) preliminarily treated with oleic acid (OA) or polyvinylpyrrolidone (PVP), whereas no shell is revealed on the surface of pristine MFO NPs. High magnetization is revealed for the developed ME NPs based on PVP- and OA-functionalized MFO NPs (18.68 ± 0.13 and 20.74 ± 0.22 emu g-1 , respectively). Moreover, ME NPs demonstrate 95% degradation of a model pollutant Rhodamine B within 2.5 h under an external AC magnetic field (150 mT, 100 Hz). Thus, the developed biocompatible core-shell ME NPs of MFO and BCZT can be considered as a promising tool for non-invasive biomedical applications, environmental remediation, and hydrogen generation for renewable energy sources.

Dynamical phenomena developed by a spiralling stretchable sheet in magnetized Casson-spinel ferrite nanofluid

Nanofluid research has sparked widespread attention due to its immense implementations in various courses, including chemical engineering, microelectronics, solar energy, cooling systems, electronics, power-saving, etc. This research offers modelling and numerical simulation for the magnetized Casson-based spinel ferrite (MnFe2O4) nanofluid stream owing to a spiralling stretchable sheet placed in a Darcy permeable medium. Diverse impacts like nonlinear heat radiation, viscous and Joule warms, and heat generation/absorption are considered in stimulating heat exchange. Under the imposed physical assumptions, equations governing the flow and heat flow are modelled. The partial derivative model is transferred to the ordinary derivative model by utilising compatible similarity variables. The resulting nonlinear linked ordinary derivative model is tackled computationally by the 4th-order Runge-Kutta integration procedure, accomplishing the best strategy shooting algorithm based on the built-in function of the bvp4c solver in MATLAB. Different attributes of the considered flow phenomenon corresponding to the pertinent model parameters are disclosed effectively via graphs and tables. Some leading outcomes are that amplification is examined in the thermal field and allied zone thickness responding to the radiation parameter and Biot number. With the upgraded rotation parameter, an augmentation is developed in the absolute value of the local skin friction coefficients. Moreover, amplifying the rotation parameter enfeebles the local Nassault number. This modelling could be effective in manufacturing and technological processes like polymeric material extrusion, stretchable/shrinkable packaging, and designing magnetic storage devices.

A Strategy for Tuning the Structure, Morphology, and Magnetic Properties of MnFe2O4/SiO2 Ceramic Nanocomposites via Mono-, Di-, and Trivalent Metal Ion Doping and Annealing

This work presents the effect of monovalent (Ag⁺, Na⁺), divalent (Ca²⁺, Cd²⁺), and trivalent (La³⁺) metal ion doping and annealing temperature (500, 800, and 1200 °C) on the structure, morphology, and magnetic properties of MnFe₂O₄/SiO₂ ceramic nanocomposites synthesized via sol-gel method. Fourier-transform infrared spectroscopy confirms the embedding of undoped and doped MnFe₂O₄ nanoparticles in the SiO₂ matrix at all annealing temperatures. In all cases, the X-ray diffraction (XRD) confirms the formation of MnFe₂O₄. In the case of undoped, di-, and trivalent metal-ion-doped gels annealed at 1200 °C, three crystalline phases (cristobalite, quartz, and tridymite) belonging to the SiO₂ matrix are observed. Doping with mono- and trivalent ions enhances the nanocomposite's structure by forming single-phase MnFe₂O₄ at low annealing temperatures (500 and 800 °C), while doping with divalent ions and high annealing temperature (1200 °C) results in additional crystalline phases. Atomic force microscopy (AFM) reveals spherical ferrite particles coated by an amorphous layer. The AFM images showed spherical particles formed due to the thermal treatment. The structural parameters calculated by XRD (crystallite size, crystallinity, lattice constant, unit cell volume, hopping length, density, and porosity) and AFM (particle size, powder surface area, and thickness of coating layer), as well as the magnetic parameters (saturation magnetization, remanent magnetization, coercivity, and anisotropy constant), are contingent on the doping ion and annealing temperature. By doping, the saturation magnetization and magnetocrystalline anisotropy decrease for gels annealed at 800 °C, but increase for gels annealed at 1200 °C, while the remanent magnetization and coercivity decrease by doping at both annealing temperatures (800 and 1200 °C).

Research progress in green synthesis of manganese and manganese oxide nanoparticles in biomedical and environmental applications - A review

Nanomaterials and nanotechnology have this unassailable position for environmental remediation and medicine. Currently, global environmental pollution and public health problems are increasing and need to be urgently addressed. Manganese (Mn) is one of the essential metal elements for plants and animals, it is necessary to integrate with nanotechnology. Mn and Mn oxide (MnO) nanoparticles (NPs) have applications in dye degradation, biomedicine, electrochemical sensors, plant and animal growth, and catalysis. However, the current research is limited, especially in terms of optimal synthesis of Mn and MnO NPs, separation, purification conditions, and the development of potential application areas is too basic and do not support by in-depth studies. Hence, this review comprehensively discusses the classification, green synthesis methods, and applications of Mn and MnO NPs in biomedical, environmental, and other fields and gives a perspective for the future.

Recent advances in conducting polymer-based magnetic nanosorbents for dyes and heavy metal removal: fabrication, applications, and perspective

Globally, treating and disposing of industrial pollutants is a techno-economic challenge. Industries' large production of harmful heavy metal ions (HMIs) and dyes and inappropriate disposal worsen water contamination. Much attention is required on the development of efficient and cost-effective technologies and approaches for removing toxic HMIs and dyes from wastewater as they pose a severe threat to public health and aquatic ecosystems. Due to the proven superiority of adsorption over other alternative methods, various nanosorbents have been developed for the efficient removal of HMIs and dyes from wastewater and aqueous solutions. Being a good adsorbent, conducting polymer-based magnetic nanocomposites (CP-MNCPs) has drawn more attention for HMIs and dye removal. Conductive polymers' pH-responsiveness makes CP-MNCP ideal for wastewater treatment. The composite material absorbed dyes and/or HMIs from contaminated water could be removed by changing the pH. Here, we review the production strategies and applications of CP-MNCPs for HMIs and dye removal. The review also sheds light on the adsorption mechanism, adsorption efficiency, kinetic and adsorption models, and regeneration capacity of the various CP-MNCPs. To date, various modifications to conducting polymers (CPs) have been explored to improve the adsorption properties. It is evident from the literature survey that the combination of SiO₂, graphene oxide (GO), and multi-walled carbon nanotubes (MWCNTs) with CPs-MNCPs enhances the adsorption capacity of nanocomposites to a large extent, so future research should lean toward the development of cost-effective hybrid CPs-nanocomposites.

Mineral-Enhanced Manganese Ferrite with Multiple Enzyme-Mimicking Activities for Visual Detection of Disease Markers

Local geometric configurations of metal cations in inorganic enzyme mimics determine their catalytic behaviors, while their optimization remains challenging. Herein, kaolinite, a naturally layered clay mineral, achieves the optimization of cationic geometric configuration in manganese ferrite. We demonstrate that the exfoliated kaolinite induces the formation of defective manganese ferrite and makes more iron cations fill into the octahedral sites, significantly enhancing the multiple enzyme-mimicking activities. The steady-state kinetic assay results show that the catalytic constant of composites toward 3,3',5,5'-tetramethylbenzidine (TMB) and H₂O₂ are more than 7.4- and 5.7-fold higher than manganese ferrite, respectively. Furthermore, density functional theory (DFT) calculations reveal that the outstanding enzyme-mimicking activity of composites is attributed to the optimized iron cation geometry configuration, which has a higher affinity and activation ability toward H₂O₂ and lowers the energy barrier of key intermediate formation. As a proof of concept, the novel structure with multiple enzyme-mimicking activities amplifies the colorimetric signal, realizing the ultrasensitive visual detection of disease marker acid phosphatase (ACP), with a detection limit of 0.25 mU/mL. Our findings provide a novel strategy for the rational design of enzyme mimics and an in-depth investigation of their enzyme-mimicking properties.

Prospect of nanomaterials as antimicrobial and antiviral regimen

In recent years studies of nanomaterials have been explored in the field of microbiology due to the increasing evidence of antibiotic resistance. Nanomaterials could be inorganic or organic, and they may be synthesized from natural products from plant or animal origin. The therapeutic applications of nano-materials are wide, from diagnosis of disease to targeted delivery of drugs. Broad-spectrum antiviral and antimicrobial activities of nanoparticles are also well evident. The ratio of nanoparticles surface area to their volume is high and that allows them to be an advantageous vehicle of drugs in many respects. Effective uses of various materials for the synthesis of nanoparticles impart much specificity in them to meet the requirements of specific therapeutic strategies. The potential therapeutic use of nanoparticles and their mechanisms of action against infections from bacteria, fungi and viruses were the focus of this review. Further, their potential advantages, drawbacks, limitations and side effects are also included here. Researchers are characterizing the exposure pathways of nano-medicines that may cause serious toxicity to the subjects or the environment. Indeed, societal ethical issues in using nano-medicines pose a serious question to scientists beyond anything.

Antitumor Activity of PEGylated and TEGylated Phenothiazine Derivatives: Structure–Activity Relationship

The paper aims to investigate the antitumor activity of a series of phenothiazine derivatives in order to establish a structure–antitumor activity relationship. To this end, PEGylated and TEGylated phenothiazine have been functionalized with formyl units and further with sulfonamide units via dynamic imine bonds. Their antitumor activity was monitored in vitro against seven human tumors cell lines and a mouse one compared to a human normal cell line by MTS assay. In order to find the potential influence of different building blocks on antitumor activity, the antioxidant activity, the ability to inhibit farnesyltransferase and the capacity to bind amino acids relevant for tumor cell growth were investigated as well. It was established that different building blocks conferred different functionalities, inducing specific antitumor activity against the tumor cells.

In-situ fabrication of manganese ferrite grafted polyaniline nanocomposite: A magnetically reusable visible light photocatalyst and a robust electrode material for supercapacitor

Herein, we reported the in-situ preparation of manganese ferrite (MnFe₂O₄) grafted polyaniline (Pani), a magnetic nanocomposite for the potential visible light photocatalytic material as well as electrode material for supercapacitor. The physical characterization of the prepared nanoparticle and nanocomposite was examined with various spectroscopic and microscopic analyses. The peaks observed in the X-ray diffraction study confirm the face-centered cubic phase of MnFe₂O₄ nanoparticles with a grain size of ∼17.6 nm. The surface morphology analysis revealed the uniform distribution of spherical-like MnFe₂O₄ nanoparticles on the surface of Pani. The degradation of malachite green (MG) dye under exposure to visible light was investigated using MnFe₂O₄/Pani nanocomposite as a photocatalyst. The results exposed the faster degradation of MG dye was accomplished by MnFe₂O₄/Pani nanocomposite than MnFe₂O₄ nanoparticles. The energy storage performance of the MnFe₂O₄/Pani nanocomposite was analyzed through cyclic voltammetry, galvanostatic charge/discharge, and electrochemical impedance spectroscopy analyses. The results exposed that the MnFe₂O₄/Pani electrode achieved a capacitance of 287.1 F/g than the MnFe₂O₄ electrode (94.55 F/g). Further, the respectable capacitance of 96.92% was achieved even after 3000 repetitive cycles stability . Based on the outcomes, the MnFe₂O₄/Pani nanocomposite can be suggested as a promising material for both photocatalytic and supercapacitor applications.

Magnetic Bacterial Cellulose Biopolymers: Production and Potential Applications in the Electronics Sector

Bacterial cellulose (BC) is a biopolymer that has been widely investigated due to its useful characteristics, such as nanometric structure, simple production and biocompatibility, enabling the creation of novel materials made from additive BC in situ and/or ex situ. The literature also describes the magnetization of BC biopolymers by the addition of particles such as magnetite and ferrites. The processing of BC with these materials can be performed in different ways to adapt to the availability of materials and the objectives of a given application. There is considerable interest in the electronics field for novel materials and devices as well as non-polluting, sustainable solutions. This sector influences the development of others, including the production and optimization of new equipment, medical devices, sensors, transformers and motors. Thus, magnetic BC has considerable potential in applied research, such as the production of materials for biotechnological electronic devices. Magnetic BC also enables a reduction in the use of polluting materials commonly found in electronic devices. This review article highlights the production of this biomaterial and its applications in the field of electronics.

Mechanical performance and thermal stability of hardened Portland cement-recycled sludge pastes containing MnFe2O4 nanoparticles

This study focused on investigating the possibility of using different ratios (5, 10, 15 mass%) of recycled alum sludge (RAS) as partial replacement of ordinary Portland cement (OPC), to contribute to solving the problems encountered by cement production as well as stockpiling of large quantities of water-treated sludge waste. MnFe₂O₄ spinel nanoparticles (NMFs) were used to elaborate the mechanical characteristics and durability of different OPC-RAS blends. The outcomes of compressive strength, bulk density, water absorption, and stability against firing tests fastened the suitability of utilization of RAS waste for replacing OPC (maximum limit 10%). The inclusion of different doses of NMFs nanoparticles (0.5, 1 and 2 mass %) within OPC-RAS pastes, motivates the configuration of hardened nanocomposites with improved physico-mechanical characteristics and stability against firing. Composite made from 90% OPC-10% RAS-0.5% NMFs presented the best characteristics and consider the optimal choice for general construction applications. Thermogravimetric analysis (TGA/DTG), X-ray diffraction analysis (XRD), and scanning electron microscope (SEM) techniques. affirmed the positive impact of NMFs particles, as they demonstrated the formation of enormous phases as ilvaite (CFSH), calcium silicate hydrates (CSHs), MnCSH, Nchwaningite [Mn₂ SiO₃(OH)₂ H₂O], [(Mn, Ca) Mn₄O₉⋅3H₂O], calcium aluminosilicate hydrates (CASH), Glaucochroite [(Ca, Mn)₂SiO₄, and calcium ferrite hydrate (CFH). These hydrates boosted the robustness and degradation resistance of the hardened nanocomposites upon firing.

A Simplified and Efficient Method for Production of Manganese Ferrite Magnetic Nanoparticles and Their Application in DNA Isolation

A simplified, fast, and effective production method has been developed for the synthesis of manganese ferrite (MnFe₂O₄) magnetic nanoparticles (MNPs). In addition to the wide applicability of MnFe₂O₄ MNPs, this work also reports their application in DNA isolation for the first time. An ultrasonic-cavitation-assisted combustion method was applied in the synthesis of MnFe₂O₄ MNPs at different furnace temperatures (573 K, 623 K, 673 K, and 773 K) to optimize the particles' properties. It was shown that MnFe₂O₄ nanoparticles synthesized at 573 K consist of a spinel phase only with adequate size and zeta potential distributions and superparamagnetic properties. It was also demonstrated that superparamagnetic manganese ferrite nanoparticles bind DNA in buffer with a high NaCl concentration (2.5 M), and the DNA desorbs from the MNPs by decreasing the NaCl concentration of the elution buffer. This resulted in a DNA yield comparable to that of commercial DNA extraction products. Both the DNA concentration measurements and electrophoresis confirmed that a high amount of isolated bacterial plasmid DNA (pDNA) with adequate purity can be extracted with MnFe₂O₄ (573 K) nanoparticles by applying the DNA extraction method proposed in this article.

Synthesis and Cytotoxicity Assessment of Citrate-Coated Calcium and Manganese Ferrite Nanoparticles for Magnetic Hyperthermia

Calcium-doped manganese ferrite nanoparticles (NPs) are gaining special interest in the biomedical field due to their lower cytotoxicity compared with other ferrites, and the fact that they have improved magnetic properties. Magnetic hyperthermia (MH) is an alternative cancer treatment, in which magnetic nanoparticles promote local heating that can lead to the apoptosis of cancer cells. In this work, manganese/calcium ferrite NPs coated with citrate (Ca_xMn_1-xFe₂O₄ (x = 0, 0.2, 1), were synthesized by the sol-gel method, followed by calcination, and then characterized regarding their crystalline structure (by X-ray diffraction, XRD), size and shape (by Transmission Electron Microscopy, TEM), hydrodynamic size and zeta potential (by Dynamic Light Scattering, DLS), and heating efficiency (measuring the Specific Absorption Rate, SAR, and Intrinsic Loss Power, ILP) under an alternating magnetic field. The obtained NPs showed a particle size within the range of 10 nm to 20 nm (by TEM) with a spherical or cubic shape. Ca_0.2Mn_0.8Fe₂O₄ NPs exhibited the highest SAR value of 36.3 W/g at the lowest field frequency tested, and achieved a temperature variation of ~7 °C in 120 s, meaning that these NPs are suitable magnetic hyperthermia agents. In vitro cellular internalization and cytotoxicity experiments, performed using the human cell line HEK 293T, confirmed cytocompatibility over 0-250 µg/mL range and successful internalization after 24 h. Based on these studies, our data suggest that these manganese-calcium ferrite NPs have potential for MH application and further use in in vivo systems.