Manganese Ferrite Nanoparticles Research Articles

Coating Engineering of MnFe2O4 Nanoparticles with Superhigh T2 Relaxivity and Efficient Cellular Uptake for Highly Sensitive Magnetic Resonance Imaging

Superparamagnetic nanoparticles with superhigh T2 relaxivity and cellular uptake are strongly desired for ultrasensitive magnetic resonance imaging (MRI). Towards this end, highly monodispersed manganese ferrite nanoparticles (MNPs, 6 nm) with mPEG‐g‐PEI and PEG coatings as model system are employed in this study to investigate the coating engineering for simultaneously high T2 relaxivity and cellular uptake. The quantitative evaluations of the intracellular uptake indicate that mPEG‐g‐PEI modified MNPs possess highly efficient cellular uptake, 2.4‐fold larger than that with mPEG coating. More significantly, this coating simultaneously leads to a remarkably high T2 relaxivity up to 331.8 mm−1 s−1, which is 4 times larger than that of the mPEG control and the largest value reported for superparamagnetic iron oxides with similar size. Modeling analysis reveals that the superior relaxivity is mainly attributed to the largely reduced diffusivity of water molecules trapped in the mPEG‐g‐PEI net. Further MRI of MDA‐MB‐231 breast cancer cells loaded MNPs with mPEG‐g‐PEI coating demonstrated the strong MR contrast in vitro effect with a T2 relaxivity as high as 92.6 mm−1 s−1, 2.5‐folds larger than reported 10 nm MNPs. This study provides a universal strategy of coating engineering of various magnetic nanoparticles for highly sensitive MRI.

Synthesis of MnFe2O4 nanocrystals by wet-milling under atmospheric conditions

This work reports an original method for synthesis of well-crystallized manganese ferrite (MnFe2O4) nanoparticles via a high energy wet milling technique under atmospheric conditions, starting from metallic Mn and Fe powders in the presence of distilled water. The effects of milling conditions on the formation and magnetic properties of MnFe2O4 nanoparticles were investigated in detail. Fully stoichiometric MnFe2O4 nanocrystals with an average crystallite size of 14.5nm were produced after 24h of milling. As-synthesized MnFe2O4 nanocrystals were found to show soft magnetic behavior at room temperature with saturation magnetization of 53emu/g. Due to reduced thermal effects, the saturation magnetization increased to 68emu/g at 5K. Results show that this method is simple and efficient for the mass production of MnFe2O4 nanoparticles.

In vitro application of Mn-ferrite nanoparticles as novel magnetic hyperthermia agents.

Manganese ferrite nanoparticles were synthesized by a facile, low-cost, environmentally friendly and high yield methodology based on the aqueous co-precipitation of proper salts. Firstly, structural, morphological and magnetic characterization schemes were performed to determine crucial factors for optimizing their heating potential, such as size, polydispersity, saturation magnetization and coercivity. In an effort to simulate the in vivo environment of animal tissue phantoms and study the thermal heating effects resulting from Brownian motion and hysteresis losses, nanoparticles at various concentrations were embedded in aqueous media of varying agar concentration. During the in vitro application healthy cells (primary bone marrow-derived osteoblasts and 3T3-L1 fibroblast-like preadipocytes) and human osteosarcoma Saos-2 cells were incubated with manganese ferrite nanoparticles. The heating profile of the particles was studied at different concentrations and in correlation with their potential cytotoxic effect. Our results revealed concentration dependent cytotoxicity profile and uptake efficiency together with variable specific loss power values yet with fast thermal response, opening novel pathways in material selection as hyperthermia agents.

Efficient synthesis of novel spiro-furo-pyrido-pyrimidine-indolines by manganese ferrite nanoparticles as a highly active magnetically reusable nanocatalyst in water

Download options Please wait... Supplementary files Supplementary information PDF (1490K) Article information DOI https://doi.org/10.1039/C3NJ00940H Article type Paper Submitted 14 Aug 2013 Accepted 16 Oct 2013 First published 17 Oct 2013 Download Citation New J. Chem., 2014,38, 348-357 BibTex EndNote MEDLINE ProCite ReferenceManager RefWorks RIS Permissions Request permissions Efficient synthesis of novel spiro-furo-pyrido-pyrimidine-indolines by manganese ferrite nanoparticles as a highly active magnetically reusable nanocatalyst in water H. Naeimi, Z. Rashid, A. H. Zarnani and R. Ghahremanzadeh, New J. Chem., 2014, 38, 348 DOI: 10.1039/C3NJ00940H To request permission to reproduce material from this article, please go to the Copyright Clearance Center request page. If you are an author contributing to an RSC publication, you do not need to request permission provided correct acknowledgement is given. If you are the author of this article, you do not need to request permission to reproduce figures and diagrams provided correct acknowledgement is given. If you want to reproduce the whole article in a third-party publication (excluding your thesis/dissertation for which permission is not required) please go to the Copyright Clearance Center request page. Read more about how to correctly acknowledge RSC content. Social activity Tweet Share Search articles by author Hossein Naeimi Zahra Rashid Amir Hassan Zarnani Ramin Ghahremanzadeh

Manganese ferrite nanoparticle catalyzed tandem and green synthesis of spirooxindoles

PEG-400 as a nontoxic, green and reusable solvent was used for the synthesis of novel spiro-furo-pyridine-indoline-carbonitriles in the presence of a magnetically recoverable nanocatalyst.

Magnetic nanoparticle-loaded polymer nanospheres as magnetic hyperthermia agents.

Uniform magnetic nanoparticle-loaded polymer nanospheres with different loading contents of manganese ferrite nanoparticles were successfully synthesized using a flexible emulsion process. The MnFe2O4-loaded polymer nanospheres displayed an excellent dispersibility in both water and phosphate buffer saline. The effect of loading ratio and size of MnFe2O4 nanoparticles within the nanospheres on the specific absorption rate (SAR) under an alternating magnetic field was investigated. Our results indicate that a large size (here 18 nm) and a low loading ratio are preferable for a high SAR. For a smaller particle size (6 nm), the low loading ratio did not result in an enhancement of the SAR value, while a very low SAR value is expected for 6 nm. In addition, the SAR of low-content MnFe2O4 (18 nm)-loaded polymer nanospheres in the agarose gel which is simulated for in vivo environment is the highest among the samples and does not change substantially in physiological environments. This differs largely from the behaviour of singly dispersed nanoparticles. Our results have paved the way for the design of MnFe2O4-loaded polymer nanospheres as magnetic hyperthermia agents for in vivo bio-applications.

Magnetic nanoparticle-based immunoassay for rapid detection of influenza infections by using an integrated microfluidic system

Magnetic manganese ferrite (MnFe2O4) nanoparticles with approximately 100nm in diameter were used to improve the performance of an immunoassay for detecting influenza infections. The synthesized nanoparticles were tested for long-term storage to confirm the stability of their thermal decomposition process. Then, an integrated microfluidic system was developed to perform the diagnosis process automatically, including virus purification and detection. To apply these nanoparticles for influenza diagnosis, a micromixer was optimized to reduce the dead volume within the microfluidic chip. Furthermore, the mixing index of the micromixer could achieve as high as 97% in 2seconds. The optical signals showed that this nanoparticle-based immunoassay with dynamic mixing could successfully achieve a detection limit of influenza as low as 0.007 HAU. When compared with the 4.5-μm magnetic beads, the optical signals of the MnFe2O4 nanoparticles were twice as sensitive. Furthermore, five clinical specimens were tested to verify the usability of the developed system. From the Clinical EditorIn this study, magnetic manganese ferrite nanoparticles were used to improve the performance of a novel immunoassay for the rapid and efficient detection of influenza infections.

Sonochemical Synthesis and Characterization of Manganese Ferrite Nanoparticles

This paper reports sonochemical synthesis and characterization of Mn–ferrite nanoparticles using acetates precursors. Mn–ferrite synthesis requires external calcination of oxide precursors formed by sonication. pH does not play a dominant role in the synthesis. Collisions between metal oxide particles induced by shock waves generated by transient cavitation are unable to cross the activation energy barrier for the formation of ferrite. The calcination temperature is a significant parameter that influences the magnetic properties of ferrites. The size, coercivity, and saturation magnetization of ferrite particles increases with the calcination temperature. Ferrites formed at calcination temperatures of 650, 750, and 850 °C show ferromagnetic behavior with easy axis magnetization. Calcination at 950 °C leads to the formation of rods with grain growth that introduces large shape anisotropy. The magnetization curve for rods does not reach saturation, indicating paramagnetic behavior. The cause leading to this...

Galactosylated manganese ferrite nanoparticles for targeted MR imaging of asialoglycoprotein receptor

Cancer cells can express specific biomarkers, such as cell membrane proteins and signaling factors. Thus, finding biomarkers and delivering diagnostic agents are important in the diagnosis of cancer. In this study, we investigated a biomarker imaging agent for the diagnosis of hepatic cancers. The asialoglycoprotein receptor (ASGPr) was selected as a biomarker for hepatoma cells and the ASGPr-targetable imaging agent bearing a galactosyl group was prepared using manganese ferrite nanoparticles (MFNP) and galactosylgluconic acid. The utility of the ASGPr-targetable imaging agent, galactosylated MFNP (G-MFNP) was assessed by several methods in ASGPr-expressing HepG2 cells as target cells and ASGPr-deficient MCF7 cells. Physical and chemical properties of G-MFNP were examined using Fourier-transform infrared spectroscopy, dynamic light scattering, zeta potential analysis, and transmission electron microscopy. No significant cytotoxicity was observed in either cell line. Targeting ability was assessed using flow cytometry, magnetic resonance imaging, inductively coupled plasma atomic emission spectroscopy, absorbance analysis, dark-field microscopy, Prussian blue staining, and transmission electron microscopy. We demonstrated that G-MFNP target successfully and bind to ASGPr-expressing HepG2 cells specifically. We suggest that these results will be useful in strategies for cancer diagnoses based on magnetic resonance imaging.

Real-time infrared thermography detection of magnetic nanoparticle hyperthermia in a murine model under a non-uniform field configuration

Purpose: Magnetic nanoparticle hyperthermia consists of an increase of the temperature of magnetic nanoparticles (heat centres) due to the interaction of their magnetic moments with an alternating magnetic field. In vivo experiments using this method usually use a few fibre-optic thermometers inserted in the animal body to monitor the heat deposition. As a consequence, only a few points of the 3D temperature distribution can be monitored by this invasive procedure. It is the purpose of this work to show that non-invasive infrared thermography is able to detect, in real time, magnetic nanoparticle hyperthermia as well as monitor the harmful field-induced eddy currents in a murine model with a subcutaneous tumour. This surface temperature measurement method has the potential to give information about the intratumoral temperature. Materials and methods: The non-invasive magnetic hyperthermia experiments were performed at 300 kHz in non-uniform field configuration conditions in healthy mice and murine tumour induced by sarcoma S180. A soft ferrite-based biocompatible magnetic colloid consisting of manganese–ferrite nanoparticles surface-coated with citric acid were used in the experiments, which were extensively characterised by several techniques (transmission electron microscopy (TEM), X-ray diffraction (XRD), vibrating sample magnetometer (VSM)). The amplitude of the alternating magnetic fields was obtained from measurements using an AC field probe at similar experimental conditions. The temperature measurements were obtained from an infrared thermal camera and a fibre-optic thermometer. Results: Three-minute magnetic hyperthermia experiments revealed surface temperature increase as high as 11 °K in healthy and (5 °K in S180 tumour) animals when injecting subcutaneously 2 mg of magnetic nanoparticles (86 μL of magnetic fluid), in contrast to around 1.5 °K (for healthy) and 2.5 °K (for cancerous) animals in experiments without the colloid due to field-induced eddy currents at the animal surface. The thermographic temperature measurements were found to agree with the fibre-optic measurements within a 5% error, and were associated with the skin emissivity angle of dependence in the experimental set-up. On the other hand, a 30-min magnetic nanoparticle hyperthermia revealed surface temperature increases as high as 12 °K close to the injection site, while above 2–3 cm no significant temperature increase was observed. Curiously, the intratumoral temperature, monitored by a fibre-optic sensor, was found to be almost the same as the thermal camera surface temperature after achieving an equilibrium temperature regime. From the observed isotherms at the animal surface, using an analytical heat conduction model, taking into account surface conductance, we estimate a magnetic heating power of 0.45 W/cm3 and a specific loss power (SLP) of 85 W/g for a field of the order of only 10 kA/m at the injection site region. Conclusions: The results indicate that infrared thermography may be a promising tool for both early cancer detection and for hyperthermia treatment (at least for subcutaneous tumours), since the method permits access to information about the intratumoral temperature during a real-time magnetic hyperthermia as well as to estimate the in vivo nanoparticles SLP.

Manganese ferrite nanoparticle: Synthesis, characterization, and photocatalytic dye degradation ability

In this paper, manganese ferrite nanoparticle (MnFe2O4) (MFN) was synthesized. Photocatalytic degradation of dye using MFN and hydrogen peroxide (H2O2) from colored wastewater was studied. Reactive dyes, Reactive Red 198 (RR198), and Reactive Red 120 (RR120), were used as model compounds. The characteristics of MFN were investigated using Fourier transform infrared, X-ray diffraction, and scanning electron microscope. Dye degradation was studied using UV-vis spectrophotometer and ion chromatography. The effects of MFN dosage, salt, and initial dye concentration on dye degradation were evaluated. Formate, acetate, and oxalate anions were detected as dominant aliphatic intermediate. Inorganic anions (nitrate and sulfate anions) were detected as the mineralization products of dyes during the degradation processes. The results indicated that the MFN could be used as a magnetic catalyst to degrade reactive dyes from wastewater.

A smart nanoporous theranostic platform for simultaneous enhanced MRI and drug delivery

Use of inorganic nanoparticles is expectedly improving the prospects of chemotherapy and diagnosis. Here, we report a facile approach to synthesize water dispersible, superparamagnetic manganese ferrite (MnFe2O4) nanoparticles at relatively low temperature. Subsequently, these MnFe2O4 nanoparticles are integrated with acid degradable mesoporous ZnO nanoparticles to attain a platform for simultaneous magnetic resonance imaging (MRI) and acid triggered anticancer drug delivery. Drug release was evaluated by tuning the pH of buffer solutions to mimic intracellular environment, which demonstrated a biorelevant acid sensitive release behavior. In vitro cell study congruently demonstrated an excellent concentration-dependent cytotoxicity on pancreatic cancer cells, with IC50 of 3μg/mL composite concentration. As far as imaging results are concerned, relaxivity value (r2) value of our system was found to be measurably higher than commercial T2 MRI contrast agent Ferridex (63.5mM−1s−1).This smart nanosystem can be a step forward towards the realization of concurrent effective therapy, monitoring of nanocarrier distribution and disease evolution.

Transport properties of nano manganese ferrite–propylene glycol dispersion (nanofluids): new observations and discussion

Experiments were conducted on the preparation of manganese ferrite nanoparticles and their surface modification for dispersion in propylene glycol. The appropriate concentrations of ferrous sulphate and manganese sulphate (precursors) for synthesis of uniform Mn0.43Fe2.57O4 nanoparticles (size range ~20–25 nm) were found to be 0.05 and 0.025 M, respectively. These nanoparticles were coated with citric acid and dispersed in propylene glycol for the preparation of nanofluids. The effects of temperature and nanoparticle concentration on nanofluid viscosity and thermal conductivity have been studied. Our study on the influence of nanoparticle concentration on viscosity reveals the existence of a viscosity minimum for 0.25 vol% of citric acid-modified Mn0.43Fe2.57O4–propylene glycol nanofluid. A thermal conductivity enhancement of 68 % was observed for 2 vol% nanofluid. Correlating viscosity and thermal conductivity measurements, particle clustering seems to be the major factor responsible for thermal conductivity enhancement.

Size and compositionally controlled manganese ferrite nanoparticles with enhanced magnetization

A facile solvothermal approach was used to synthesize stable, superparamagnetic manganese ferrite nanoparticles with relatively small sizes (<10 nm) and enhanced magnetic features. Tetraethylene glycol has been used in all the syntheses as a biocompatible and stabilizing agent. By varying the oxidation state of manganese precursor, Mn(acac)2 to Mn(acac)3, different sizes, 8 and 5 nm, of MnFe2O4 nanoparticles were obtained respectively, while by tailoring the synthetic conditions iron-rich Mn0.77Fe2.23O4 nanoparticles have been isolated with identical sizes and enhanced saturation magnetization. The magnetization values increased from 58.2 to 68.3 Am2/kg and from 53.3 to 60.2 Am2/kg for the nanoparticles of 8 and 5 nm, respectively. Blocking temperature (T B), ranging from 80 to 180 K, and anisotropy constant (K eff), ranging from 1.5 × 105 to 4.9 × 105 J/m3, were found higher for the iron-rich samples and associated with size and composition effects.

Relaxivities of hydrogen protons in aqueous solutions of gold-coated manganese ferrite nanoparticles

Manganese ferrite nanoparticles were synthesized using the reverse micelle method and were coated with gold. TEM (transmission electron microscope) pictures showed that the shapes of the synthesized nanoparticles were almost spherical with an average diameter of 12 nm and a standard error of 4 nm. The bonding status of gold on the nanoparticle surfaces was checked using a Fourier transform infrared spectrometer (FTIR). The T1 and the T2 relaxation times of the hydrogen protons in aqueous solutions of the coated manganese-ferrite nanoparticles were determined using magnetic resonance imaging (MRI). The 1/T1 and the 1/T2 versus concentration curves for the nanoparticles showed a linear dependence. The T1 and the T2 relaxivities were found to be r1 = 6.01 ± 0.12 and r2 = 83.3 ± 0.55 mM−1s−1. The ratio of r2/r1 was 13.9; this is larger than the ratios of r2/r1 for commercial T2 MRI contrast agents, indicating that the nanoparticles studied herein can serve as a T2 contrast agent with high efficacy.

Study of the thermodynamics of chromium(III) and chromium(VI) binding to iron(II/III)oxide or magnetite or ferrite and magnanese(II) iron (III) oxide or jacobsite or manganese ferrite nanoparticles

Removal of chromium(III) or (VI) from aqueous solution was achieved using Fe3O4, and MnFe2O4 nanomaterials. The nanomaterials were synthesized using a precipitation method and characterized using XRD. The size of the nanomaterials was determined to be 22.4±0.9nm (Fe3O4) and 15.5±0.5nm (MnFe2O4). The optimal binding pH for chromium(III) and chromium(VI) were pH 6 and pH 3. Isotherm studies were performed, under light and dark conditions, to determine the capacity of the nanomaterials. The capacities for the light studies with MnFe2O4 and Fe3O4 were determined to be 7.189 and 10.63mg/g, respectively, for chromium(III). The capacities for the light studies with MnFe2O4 and Fe3O4 were 3.21 and 3.46mg/g, respectively, for chromium(VI). Under dark reaction conditions the binding of chromium(III) to the MnFe2O4 and Fe3O4 nanomaterials were 5.74 and 15.9mg/g, respectively. The binding capacity for the binding of chromium(VI) to MnFe2O4 and Fe3O4 under dark reaction conditions were 3.87 and 8.54mg/g, respectively. The thermodynamics for the reactions showed negative ΔG values, and positive ΔH values. The ΔS values were positive for the binding of chromium(III) and for chromium(VI) binding under dark reaction conditions. The ΔS values for chromium(VI) binding under the light reaction conditions were determined to be negative.

Ultrasmall Manganese Ferrite Nanoparticles as Positive Contrast Agent for Magnetic Resonance Imaging

Reducing ferromagnetic particle size is an important strategy to improve their positive effect on imaging through the suppression of their negative effect, demonstrated by ultrasmall manganese ferrite nanoparticles prepared from an environmentally-friendly aqueous route. These ultrasmall particles exhibit pronounced paramagnetic characteristics and nontoxicity, making them efficient T1-positive contrast agent and manganese contrast agents for manganese enhanced MRI.

Multifunctional PEGylated nanoclusters for biomedical applications

A simple and versatile synthesis method to form water soluble multifunctional nanoclusters using polyethylene glycol (PEG) functionalized poly(maleic anhydride-alt-1-octadecene) amphiphilic brush copolymers (PMAO-g-PEG) was presented. Simply by tuning the core size and the initial nanocrystal concentration, manganese ferrite nanoparticles (MFNPs) were used to demonstrate the versatility of tuning the loading amount of the nanoclusters. The resultant nanoclusters were found to have a well-controlled spherical shape. When Zn-doped AgInS2 quantum dots (AIZS QDs) were loaded together with the MFNP nanocrystals, bi-functional nanoclusters with fluorescent and magnetic behaviors were obtained. Such bi-functional nanoclusters were also successfully demonstrated for cellular bio-imaging. Moreover, the presence of another type of nanocrystals together with MFNPs was found to have a negligible effect on the overall properties of the nanoclusters as demonstrated by the MR relaxivity test. From the time-dependent colloidal stability test, it was found that the presence of the PEG chain grafted onto PMAO was able to reduce protein adsorption onto the nanocluster surface. An in vitro study on NIH/3T3 demonstrated the biocompatibility of the nanoclusters. Such biocompatible and colloidally stable nanoclusters with an approximate size of 80-120 nm were suitable for both MRI and cell labeling applications.

Adsorption of Lead from Aqueous Solution by Manganese Ferrite Nanoparticles

Adsorption of Lead from Aqueous Solution by Manganese Ferrite Nanoparticles

Structural and Dielectric Properties of Manganese Ferrite Nanoparticles

In this work, Manganese ferrite nanoparticles of various compositions were reproducibly synthesized via coprecipitation route. Variation in structural and dielectric properties was studied by varying the sintering temperature, sintering time and manganese to iron ratio. Structural, compositional and phase properties were investigated by X-ray diffraction (XRD) technique which confirmed the pure normal spinel structure with no other phase/impurity. Particle size, Lattice constant, measured bulk density, X-ray density, Specific Surface Area and Porosity were determined by the standard formulae. Responses of Capacitance and Dielectric constant were studied at room temperature in the frequency range of 600Hz to 1MHz by LCR meter which both showed the exponential decay at low frequency while both became nearly independent of frequency in higher frequency ranges.