MnFe2O4 NPs Research Articles

Investigation on the physico-chemical properties, hyperthermia and cytotoxicity study of magnesium doped manganese ferrite nanoparticles

The superparamagnetic nanoparticles (SPNPs) should be chemically stable and biocompatibility for magnetic hyperthermia (MHT) application. Cubic spinel structured MgFe2O4 and MnFe2O4 NPs were well studied for catalytic and sensor applications by employing their semiconducting property. Here we explore the biocompatible and soft magnetic properties of these ferrites for MHT application. Narrow size distributed Mn1-xMgxFe2O4 (x = 0.1, 0.3, 0.4 & 0.5) NPs with average crystallite size of 12 nm were synthesized by solvothermal reflux method. All compounds were crystallined in cubic spinel structure and were confirmed by X-ray diffraction, electron diffraction, high-resolution lattice fringe profiles, and infrared spectrum. Energy dispersive, photoelectron spectroscopy, and elemental mapping studies revealed that the compounds have chemical stoichiometry close to the target composition. Thermal analysis shows that the spinel compounds are thermally stable even above 800 °C. All compounds show superparamagnetic (SP) nature at room temperature and show a decrease of saturation magnetization (Ms) after substituting x = 0.3 concentration with increases of substituent Mg2+ concentration in the MnFe2O4. The x = 0.1, 0.3, 0.4 & 0.5 samples show MHT specific absorption rate (SAR) of 63.67, 108.37, 97.58, & 45.08 Wg-1 at 1 mg/mL, respectively. The decrease in SAR values is attributed to reduced magnetic moments and spin relaxation. Furthermore, monosize characteristics of Mn1-xMgxFe2O4 (x = 0.1, 0.3, 0.4, & 0.5) NPs at 0–950 g/mL concentrations were reported to be non-toxic in human breast cancer (MDA-MB-23) and human prostate cancer (PC-3) cells.

Applicability of a carbon paste electrode modified with manganese ferrite nanoparticles (MnFe2O4NPs) in simultaneous measurement of uric acid and dopamine

Considering the importance of DA (dopamine) and UA (uric acid) in the physiological process of the human body, the dosage controlling of them in the biofluids is crucial to monitor human health. Since the oxidation peaks of the DA and UA have an overlap on the bare electrode surface, the manganese ferrite nanoparticles (MnFe2O4 NPs) as the simple and cost-effective modifier can improve the electrochemical properties of the sensing interface in their simultaneous detection. Accordingly, a carbon paste electrode modified with the MnFe2O4 NPs (CPE/MnFe2O4 NPs) as the electrochemical sensor has been constructed. The embedded platform not only improved the electron transfer by increasing the surface area but also presented well-separated electro-oxidation peaks of the DA and UA with a higher current in the simultaneous detection of them. Applicability of the sensor was monitored in various concentrations of two analytes under two linear ranges of 1–50 μM for DA and 1–70 μM for UA with a limit of detection (LOD) of 0.45 μM and 0.19 μM, respectively. The sensor reliability in the presence of some common interferences confirmed selective measuring of the analytes. The satisfactory analysis results presented the sensor feasibility in the complex matrixes of the real samples, including human urine and blood serum, for the simultaneous detection of the analytes. These findings reveal the applicability of the MnFe2O4 NPs as a promising beneficial platform that may be a paradigm in other electrocatalysis fields.

Highly sensitive oxidation of MBTH/DMAB by MnFe2O4 nanoparticles as a promising method for nanozyme-based sensor development

Nanozymes are human-made nanomaterials with an intrinsic enzyme-like activity that offer a versatile alternative to natural enzymes for disease treatment, environmental remediation, and sensing. In this work, we proposed a novel spectrophotometric assay for determining the oxidase-like activity of manganese ferrite nanoparticles (MnFe2O4 NPs) based on the oxidative coupling of 3-methyl-2-benzothiazolinone-hydrazone (MBTH) and 3-(dimethylamino) benzoic acid (DMAB). The effects of pH (2−8), temperature (20–50 °C), and kinetics parameters as the effect of substrate and nanoparticle concentration on the oxidase-like activity were evaluated. The MnFe2O4 NPs (~3.19 ± 0.62 nm size) were synthesized by a co-precipitation method and characterized by TEM, SEM/EDS, VSM-SQUID, PXRD, and FTIR-ATR analyses. The optimum condition for MBTH/DMAB oxidation catalyzed by MnFe2O4 NPs was observed at pH = 3.9 and 30 °C. The MBTH/DMAB oxidation was adjusted to the Michaelis Menten kinetics model (R2 = 0.96) and showed a Km = 13.59 µM MBTH, kcat = 5.25 × 107 s−1 and kcat/Km = 3.86 × 1012 M−1 s−1. These high kcat and kcat/Km values indicate that the MBTH/DMAB couple is more sensitive than previously reported oxidase substrates by about three orders of magnitude. Hence, our findings open up a wide range of new potential applications on the development of more sensitive sensors based on the MBTH/DMAB reaction catalyzed by MnFe2O4 NPs for detecting several analytes (including alkaline phosphatase, heavy metals, dissolved oxygen in water, among others) in the medical and environmental field.

Synthesis and characterization of targeted superparamagnetic MRI contrast agent MnFe2O4-chitosan-folate

Superparamagnetic materials MnFe2O4 in nanosized form, is useful for some applications such as magnetic storage, electronic devices, biosensing and MRI contrast agent. Efficiency of the contrast agent (CA) delivery to cellular targets generally depends on the rate of vascular extravasation and pharmacokinetics in the plasma. Contrast agents with longer circulation time could show better kinetics at the target site. In this research, strategies to prolong the plasma life is conjugatingMnFe2O4 NPs with chitosan-folate. MnFe2O4 NPs were synthesized from MnCl2 with FeCl3 using a reducing agent NaOH. In other side, chitosan was conjugated with folic acid to produce chitosan-folate compounds. Then chitosan-folate was reacted with MnFe2O4 nanoparticles to produce MnFe2O4 -chitosan-folate.MnFe2O4 nanoparticles was characterized using UV Vis, FTIR, PSA and SEM EDX. The characterization of MnFe2O4 -chitosan-folate is also carried out using radioactive agent by labeling with 99mTc radionuclide which will produce the MnFe2O4 - (99m Tc) Chitosan-folate complex. The characterization tests using 99m Tc radionuclides showed yields and radiochemical purity ofmore than 95%. It indicates that the compound of MnFe2O4-chitosan-folate has been successfully synthesized. MnFe2O4-chitosan-folate nanoparticles as finished product will be used for targeted MRI Contrast agent.

Polyvinylpropyllidone decorated manganese ferrite based cues for the efficient removal of heavy metals ions from waste water

Heavy metals present in wastewater have adverse effect on human health particularly when the concentration increases above the standard values as recommended by World Health Organization (WHO). Many attempts have been made to remove toxic metals from water. In the present study, PVP@MnFe2O4 NPs as adsorbent material has been synthesized through simple, fast and ecofriendly sonochemical method. Modification of Fe3O4 NPs with Mn (II) and PVP enhanced surface area andimpart stability, respectively. The higher adsorption capacity for metal ions Pb2+,Cd2+, Ni2+ was achieved in the presence of Mn (II), which decreases the point of zero charge. PVP@MnFe2O4 NPswere characterized by scanning electron microscopy (SEM) and Fourier transform infrared spectra (FT-IR). Adsorption capacity of PVP@MnFe2O4 NPs for metals ions increased by increasing the pH from 5 to 9. Adsorption rate of metal cations on the PVP@MnFe2O4 NPs was in the following order: Pb2+ > Cd2+ > Ni2+. The efficiency of Fe3 O4 NPs, MnFe2O4 NPs, and PVP@MnFe2O4 NPs was also compared. The as synthesized PVP@MnFe2O4 NPs can be used in water treatment and other environmental applications as adsorbent.

Tailoring the magnetic hyperthermia performances of gram-bean-extract-mediated highly disperse MFe2O4 (M = Fe, Ni, Mn) nanoferrites

Magnetic hyperthermia requires a long duration of stable therapeutic temperature (43–46 °C). Because temperature kinetics mainly depends on the Brownian and Néel relaxation losses of magnetic nanoparticles (MNPs), a thorough control of these losses is essential. This can be achieved by controlling the size, shape, and surface passivation of MNPs. Although extensive studies have been conducted to develop such NPs, a bulk-yield synthesis of highly stable MNPs maintaining stable therapeutic temperatures for a long duration has not been reported. We used an efficient gram-bean-extract-(GBE)-mediated hydrothermal synthesis to obtain a uniform phase-stable bulk production of magnetic nanoferrites, Fe3O4, NiFe2O4, and MnFe2O4 that were smaller than 20 nm. The temperature kinetic plots (TKPs) of the as-hydrothermally (without GBE) synthesized NiFe2O4 and MnFe2O4 NPs (>20 nm) showed a non-adiabatic increasing trend, which exceeded the safe hyperthermia temperature zone (HTZ; 43–46 °C). On the contrary, the GBE-mediated MNPs, particularly MnFe2O4, had faster plateaus earlier in the TKPs, providing the necessary stable HTZ for more than half of the induction heating time. The pectin coatings (from the GBE) on the MNPs passivated the surfaces (preventing oxidation) and reduced the frictional losses (Brownian), which yielded the temperature plateau and stable HTZ at a longer duration. Therefore, the GBE-mediated hydrothermal route can tune the hyperthermia performances to achieve a highly stable HTZ.

Apium-derived biochar loaded with MnFe2O4@C for excellent low frequency electromagnetic wave absorption

Given the rapid development of electrommunication and radar detection technologies, low frequency electromagnetic wave materials have received more and more attention. Herein, the Apium-derived biochar loaded with MnFe2O4@C has been successfully prepared by using co-solvothermal and calcination method. The cladding carbon layer on MnFe2O4 NPs is migrated from biochar via thermal diffusion, and the biochar is covered with the ferrite NPs as well. Thus, the combination of dielectric and magnetic loss endows the composite with excellent low frequency electromagnetic absorption ability i.e. the optimal microwave absorbing intensity is −48.92 dB at 0.78 GHz with an extended effective absorbing bandwidth of 0.38–1.78 GHz for only 2.5 mm thickness, being ascribed to nature resonance, multiple interfacial and surface polarization, strong electromagnetic attenuation ability and good impedance matching property in detail. This bio-based ferrite composites have great potential in preparation of MAMs due to the advantages of extraordinary performance, lightweight property, environmental protection and easy degradation.

Manganese ferrite (MnFe2O4) as potential nanosorbent for adsorption of uranium(VI) and thorium(IV)

The adsorption behavior of U(VI) and Th(IV) metal ions by MnFe2O4 NPs was studied as a function of pH, mass of sorbent, contact time, and temperature. Kinetic data was fitted to Pseudo second-order model and qm reached maximum value at pH 3 for Th(IV) and at pH 3.0–5.0 for U(VI) after 3 h. The Langmuir, Freundlich, and Dubinin–Raduskevich isotherm equations were applied to the adsorption data and the proper constants were derived. Adsorption isotherms were studied at different temperature to find ΔH°, ΔG°, and ΔS°. Recovery was carried out by using 0.10 M of HNO3, HCl, EDTA, Na2CO3 and NaCl.

Impact of manganese ferrite (MnFe2O4) nanoparticles on growth and magnetic character of barley (Hordeum vulgare L.)

The main objective of this study was to assess the uptake and translocation of MnFe2O4 magnetic nanoparticles (MNPs) in hydroponically grown barley (Hordeum vulgare L.). Hydrothermally synthesized and well characterized MNPs (average crystallite size of 14.5 ± 0.5 nm) with varied doses (62.5, 125, 250, 500, and 1000 mg L−1) were subjected to the plants at germination and early growing stages (three weeks). The tissues analyzed by vibrating-sample magnetometer (VSM) and transmission electron microscopy (TEM) revealed the uptake and translocation of MNPs, as well as their internalization in the leaf cells. Also, elemental analysis proved that manganese (Mn) and iron (Fe) contents were ∼7–9 times and ∼4–7 times higher in the leaves of MNPs-treated plants than the ones for non-treated control, respectively. 250 mg L−1 of MNPs significantly (at least p < 0.05) promoted the fresh weight (FW, %10.25). However, higher concentrations (500 and 1000 mg L−1) remarkably reduced the increase to %8 and %5, respectively, possibly due to the restricted water uptake. Also, catalase activity was increased from 91 (μM H2O2 min−1 mg−1) to 138 in leaves, and decreased to 66 in roots upon 1000 mg L−1 of MNPs application. Chlorophyll and carotenoid contents were not significantly changed, except chlorophyll a (%6 increase at 1000 mg L−1, p < 0.05). Overall, MnFe2O4 NPs were up-taken from the roots and migrated to the leaves which promoted the growth parameters of barley. Hence, MNPs can be suggested for barley breeding programs and can be proposed as effective delivery system for agrochemicals. However, the possible negative effect of MNPs due to its potential horizontal transfer from plants to animals via the food chain must be also considered.

Enhanced Terahertz Radiation Generation of Photoconductive Antennas Based on Manganese Ferrite Nanoparticles

This paper presents a significant effect of manganese ferrite nanoparticles (MnFe2O4 NPs) on the increase of the surface photoconductivity of semiconductors. Herein, the optical characterization of photo-excited carriers of silicon coated with MnFe2O4 NPs was studied by using THz time-domain spectroscopy (THz-TDs). We observed that silicon coated with MnFe2O4 NPs provided a significantly enhanced attenuation of THz radiation in comparison with bare silicon substrates under laser irradiation. The experimental results were assessed in the context of a surface band structure model of semiconductors. In addition, photoconductive antennas coated with MnFe2O4 NPs significantly improved the efficiency of THz radiation generation and signal to noise ratio of the THz signal. This work demonstrates that coating with MnFe2O4 NPs could improve the overall performance of THz systems, and MnFe2O4 NPs could be further used for the implementation of novel optical devices.

Controlled synthesis of MnFe2O4 nanoparticles and Gd complex-based nanocomposites as tunable and enhanced T1/T2-weighted MRI contrast agents.

Successful development of magnetic nanoparticles (MNPs) with optimal size, shape, and composition is very desirable because they would increase the image contrast of magnetic resonance imaging (MRI). Here, we report a new precursor-mediated growth process of monodisperse MnFe2O4 NPs with controlled size and shape. MnFe2O4 NPs with plate-like shapes, spherical, and cubic can be successfully prepared by simply tuning the amount of Fe(acac)3 and Mn(acac)2 in oleic acid. Magnetism and MR properties of the particles were found to depend on their size and shape. These MnFe2O4 NPs, when conjugated with gadolinium and folic acid (FA), showed a simultaneous bright signal enhancement on the T1-weighted images and significant signal reduction on the T2-weighted image. In vitro MR imaging experiments also show that the developed multifunctional Gd:FA-DTPA-PEG-DIB-MnFe2O4 NPs enable targeted dual-contrast T1- and T2-weighted MR imaging of tumor cells over-expresses the folate receptor in vitro, and the T1- and T2-weighted MRI has been greatly improved. Our results clearly indicate that such an approach of forming multifunctional Gd:FA-DTPA-PEG-DIB-MnFe2O4 NPs is of great significance for T1- and T2-weighted MR imaging of specific cancer cells with high accuracy.