Preparation Of Iron Oxide Nanoparticles Research Articles

Gram-Scale Preparation of Iron Oxide Nanoparticles with Renal Clearance Properties for Enhanced T1-Weighted Magnetic Resonance Imaging.

Extremely small-sized iron oxide nanoparticles (ESIONs) have been accepted as a potential alternative to gadolinium-based contrast agents for enhanced T1-weighted MR imaging. Recently developed zwitterion-coated ESIONs showed a high T1 contrast power and efficient renal clearing ability, but the tedious preparation steps that required high-cost, unfriendly experimental conditions and a sophisticated phase transition process would likely hinder their clinical translation. Herein, we present a one-pot gram-scale synthesis of zwitterion-capped ultrasmall iron oxide nanoparticles (ZUIONs). The nanoparticles have a core size as small as 3.7 nm and display high colloidal stability in various buffers. The r1 relaxivity of 2.4 mM-1 s-1 and r2/r1 ratio as low as 2.2 at 1.0 T guarantee their application as effective T1 MRI contrast agents. In vivo studies showed that ZUIONs could induce a significant contrast enhancement in blood pool and be eliminated from the body mainly through the renal excretion pathway. The combined advantageous features including facile preparation, excellent biocompatibility, strong T1 MRI contrast effect, appropriate circulation time, and renal clearable property would render ZUIONs attractive for practical applications.

Cytotoxicity characteristics of green assisted-synthesized superparamagnetic maghemite (γ-Fe2O3) nanoparticles

Magnetic nanoparticles such as Fe3O4 and γ-Fe2O3 are extensively used in medical application, i.e. drug delivery, MRI, etc. Chemical toxicity and side-effect behaviors always play an important role in such applications. Thus, synthesis of such less-toxic compounds with green technology is privilege. In this study, the extract prepared from mango leaves was used for the preparation of iron oxide nanoparticles (γ-Fe2O3) using FeSO4 as iron source with the green-assisted route. The X-ray diffraction pattern indicated single-phase formation with the average crystallite size of 7 ± 2 nm. HRTEM micrographs indicated a dot-cloud-surrounded like particles ranging from 1 to 12 nm. Fourier Transform Infrared (FT-IR) spectroscopy showed two absorption bands at 457 and 634 cm−1, which are attributed to octahedral and tetrahedral sites of Fe–O band, respectively. A vibrating sample magnetometer (VSM) indicated a saturation magnetization (Ms) value about 53 emu/g with negligible coercivity (Hc), suggesting superparamagnetic behavior of the synthesized nanoparticles. The cytotoxicity was evaluated by exposing the breast cancer cell type (MCF7) to different concentrations of the γ-Fe2O3 nanoparticles. MTT assay results revealed that the growth and survival of MCF7 cells directly depend on the concentration of synthesized iron oxide nanoparticles. It was found that up to concentration of 200 µg/mL, cell survival has not yet reached 50%, which indicates the safety of nanoparticles and lack of toxicity.

Exploring drying pattern of a sessile droplet of genomic DNA in the presence of hematite nanoparticles

For the first time, drying pattern of a sessile droplet of genomic DNA, in the presence of hematite nanoparticles was sighted by polarizing optical microscopy (POM) in this research article. POM results indicated that only at an appreciably high concentration of hematite nanoparticles dried pattern of deoxyribonucleic acid from calf thymus (CT-DNA) was altered. Iron hybridized cetylpyridinium chloride was utilized for the preparation of iron oxide nanoparticles through hydrothermal method. Fourier transforms infrared spectroscopy (FTIR) and powder x-ray diffraction (PXRD) studies confirmed the formation of highly crystalline hematite i.e. α-Fe2O3 nanoparticles. Morphology of the synthesized nanoparticle was visualized by transmission electron microscope (TEM) and field emission scanning electron microscope (FESEM), which revealed that nanoparticles were rhombohedral in shape with a size of 45 ± 10 nm. Based upon all the findings, hydrothermal growth mechanism was also proposed having bilayer protection of surfactant around the nanoparticles. UV-Vis spectroscopy and fluorescence spectroscopy were explored to study the affinity of thus prepared nanoparticles towards calf thymus deoxyribonucleic acid (CT-DNA). The low value of binding constant calculated from the spectroscopy data confirmed the weak interaction between nanoparticles and the CT-DNA.

A comprehensive study on the continuous flow synthesis of supported iron oxide nanoparticles on porous silicates and their catalytic applications

The present work demonstrates an efficient continuous flow methodology for the preparation of iron oxide nanoparticles supported on porous silicates.

Ferumoxytol-enhanced magnetic resonance angiography for the assessment of potential kidney transplant recipients

ObjectivesTraditional contrast-enhanced methods for scanning blood vessels using magnetic resonance imaging (MRI) or CT carry potential risks for patients with advanced kidney disease. Ferumoxytol is a superparamagnetic iron oxide nanoparticle preparation that has potential as an MRI contrast agent in assessing the vasculature.MethodsTwenty patients with advanced kidney disease requiring aorto-iliac vascular imaging as part of pre-operative kidney transplant candidacy assessment underwent ferumoxytol-enhanced magnetic resonance angiography (FeMRA) between December 2015 and August 2016. All scans were performed for clinical indications where standard imaging techniques were deemed potentially harmful or inconclusive. Image quality was evaluated for both arterial and venous compartments.ResultsFirst-pass and steady-state FeMRA using incremental doses of up to 4 mg/kg body weight of ferumoxytol as intravenous contrast agent for vascular enhancement was performed. Good arterial and venous enhancements were achieved, and FeMRA was not limited by calcification in assessing the arterial lumen. The scans were diagnostic and all patients completed their studies without adverse events.ConclusionsOur preliminary experience supports the feasibility and utility of FeMRA for vascular imaging in patients with advanced kidney disease due for transplant listing, which has the advantages of obtaining both arteriography and venography using a single test without nephrotoxicity.Key Points• Evaluation of vascular disease is important in planning kidney transplantation.• Standard vascular imaging methods are often problematic in kidney disease patients.• FeMRA has the advantage of arteriography and venography in a single test.• FeMRA is safe and non-nephrotoxic.• FeMRA is not limited by arterial calcification.

The fabrication of iron oxide nanoparticle-nanofiber composites by electrospinning and their applications in tissue engineering.

This paper reviews the use of iron oxide nanoparticle-nanofiber composites in tissue engineering with a focus on the electrospinning technique. Electrospinning is an established method of scaffold fabrication offering a number of key advantages which include its facile nature, with electrospun materials offering a high surface area to volume ratio, potential for the release of drugs and antimicrobials, controllable fiber diameters and high porosity and permeability. A number of different techniques for the preparation of iron oxide nanoparticles including their functionalization are discussed along with their applications in the biomedical field. The review then focusses on the fabrication of nanoparticle-nanofiber composite scaffolds formed using electrospinning. The advantages and disadvantages of current fabrication techniques are discussed including the fabrication of nanofibers using pre-synthesized nanoparticles and post-treatment synthesized nanoparticles. We demonstrate that emerging in-situ synthesis techniques show promise by offering a reduced number of steps and simpler procedures for the production of magnetic scaffolds. These scaffolds have a number of applications in tissue engineering, allowing for improved bone and tissue repair.

Preparation of iron oxide nanoparticles doped by chromium for application in water–gas shift reaction

An efficient preparation method of chromium-doped iron oxide nanoparticles of controlled size, chromium content and catalytic activity was developed. The catalysts were synthesized in an acidic hydrolysis of ferric chloride in order to obtain suspensions of spherical iron oxide nanoparticles with an average size of 10 and 100nm. After purification, the suspensions were transformed into powders. Afterwards, by a wet-impregnation and calcination chromium cations were incorporated to the nanoparticle structure without changing their size. The catalysts were characterized by powder X-ray diffraction (XRD), Raman spectroscopy, N2 adsorption (BET) and scanning electron microscopy (SEM). The activity of obtained samples was tested in a high temperature water gas shift reaction (HT-WGS) and compared with the results gained for chromium-free nanoparticles of similar sizes. The analysis of Raman spectra revealed that at elevated temperature iron hydroxyoxides are transformed to hematite (α-Fe2O3) and then, under catalytic conditions, to magnetite (Fe3O4) which is an active phase in the HT-WGS reaction. The chromium incorporated into the nanoparticles prevented a thermal sintering of nanocrystals, leading to an efficient catalyst performance. It was also shown that chromium-doped α-Fe2O3 nanoparticles of the size of 100nm, after the transformation to the magnetite phase, allowed to obtain a high carbon oxide conversion approaching the thermodynamic limit for temperatures above 500°C .

Impact of semi-solid formulations on skin penetration of iron oxide nanoparticles

BackgroundThis work aimed to provide useful information on the incidence of the choice of formulation in semi-solid preparations of iron-oxide nanoparticles (IONs). The appropriate analytical methods to assess the IONs physical stability and the effect of the semi-solid preparations on IONs human skin penetration were discussed. The physical stability of IONs (Dh = 31 ± 4 nm; ζ = −65 ± 5 mV) loaded in five semi-solid preparations (0.3% w/v), namely Carbopol gel (CP), hydroxyethyl cellulose gel (HEC), carboxymethylcellulose gel (CMC), cetomacrogol cream (Cet) and cold cream was assessed by combining DLS and low-field pulsed NMR data. The in vitro penetration of IONs was studied using human epidermis or isolated stratum corneum (SC).ResultsReversible and irreversible IONs aggregates were evidenced only in HEC and CMC, respectively. IONs diffused massively through SC preferentially by an intercellular pathway, as assessed by transmission electron microscopy. The semi-solid preparations differently influenced the IONs penetration as compared to the aqueous suspension. Cet cream allowed the highest permeation and the lowest retained amount, while cold cream and CP favored the accumulation into the skin membrane.ConclusionBasic cutaneous semi-solid preparations could be used to administer IONs without affecting their permeation profile if they maintained their physical stability over time. This property is better discriminated by low-field pulsed NMR measurements than the commonly used DLS measurements.

Microwave-assisted deep eutectic-solvothermal preparation of iron oxide nanoparticles for photoelectrochemical solar water splitting

Iron oxide nanoparticles, prepared using a new, efficient deep eutectic-solvothermal microwave methodology, were cast as photoanodes, showing competitive photocurrent performance.

From oleic acid-capped iron oxide nanoparticles to polyethyleneimine-coated single-particle magnetofectins

Various inorganic nanoparticle designs have been developed and used as non-viral gene carriers. Magnetic gene carriers containing polyethyleneimine (PEI), a well-known transfection agent, have been shown to improve DNA transfection speed and efficiency in the presence of applied magnetic field gradients that promote particle–cell interactions. Here we report a method to prepare iron oxide nanoparticles conjugated with PEI that: preserves the narrow size distribution of the nanoparticles, conserves magnetic properties throughout the process, and results in efficient transfection. We demonstrate the ability of the particles to electrostatically bind with DNA and transfect human cervical cancer (HeLa) cells by the use of an oscillating magnet array. Their transfection efficiency is similar to that of Lipofectamine 2000™, a commercial transfection reagent. PEI-coated particles were subjected to acidification, and acidification in the presence of salts, before DNA binding. Results show that although these pre-treatments did not affect the ability of particles to bind DNA they did significantly enhanced transfection efficiency. Finally, we show that these magnetofectins (PEI-MNP/DNA) complexes have no effect on the viability of cells at the concentrations used in the study. The systematic preparation of magnetic vectors with uniform physical and magnetic properties is critical to progressing this non-viral transfection technology.

Synthesis, characterization, applications, and challenges of iron oxide nanoparticles.

Recently, iron oxide nanoparticles (NPs) have attracted much consideration due to their unique properties, such as superparamagnetism, surface-to-volume ratio, greater surface area, and easy separation methodology. Various physical, chemical, and biological methods have been adopted to synthesize magnetic NPs with suitable surface chemistry. This review summarizes the methods for the preparation of iron oxide NPs, size and morphology control, and magnetic properties with recent bioengineering, commercial, and industrial applications. Iron oxides exhibit great potential in the fields of life sciences such as biomedicine, agriculture, and environment. Nontoxic conduct and biocompatible applications of magnetic NPs can be enriched further by special surface coating with organic or inorganic molecules, including surfactants, drugs, proteins, starches, enzymes, antibodies, nucleotides, nonionic detergents, and polyelectrolytes. Magnetic NPs can also be directed to an organ, tissue, or tumor using an external magnetic field for hyperthermic treatment of patients. Keeping in mind the current interest in iron NPs, this review is designed to report recent information from synthesis to characterization, and applications of iron NPs.

Preparation of iron oxide nanoparticles by laser ablation in DMF under effect of external magnetic field

We have studied the effect of applying an external magnetic field on the characteristics of iron oxide (IO) nanoparticles (NPs) synthesized by pulsed laser ablation in dimethylformamide (DMF). The NPs synthesized with and without applying of magnetic field were characterized by Fourier transformation infrared spectroscopy (FT-IR), UV–Vis absorption, scanning electron microscope (SEM), atomic force microscope (AFM), and X-ray diffraction (XRD). SEM results confirmed that the particle size was decreased after applying magnetic field.

Preparation of iron oxide nanoparticles functionalized with Y-shaped ligands for brain tumor targeting.

In this study, we developed functionalized iron oxide nanoparticles for brain tumor targeting. The iron oxide (Fe3O4) particles were stabilized with pluronic F127 and coupled with dopamine-terminated Y-shaped ligands (Tat peptide and transferrin) as a result of the noncovalent conjugation of dopamine (of Y-shaped ligands) and the iron oxide nanoparticles. Here, the hydrophobic domain of pluronic F127 coated on the iron oxide nanoparticles enabled the absorption of a model photosensitizing antitumor drug (chlorin e6) in the core/shell interface of the nanoparticles. The experimental results demonstrated that the Y-shaped ligands on the nanoparticles enabled a significant enhancement of in vitro/in vivo cellular uptake for human primary glioblastoma U87-MG cells as a result of multivalent endocytosis by Y-shaped ligands (transferrin receptor-mediated endocytosis and the following Tat peptide-mediated cellular interaction). Furthermore, the Ce6-loaded nanoparticles showed significant enhancement of in vitro/in vivo photodynamic U87-MG cell ablation under light illumination.

Synthesis of Iron Oxide Nanoparticles Coated Sand by Biological Method and Chemical Method

Iron oxide nanoparticles can be prepared by physical, chemical and biological methods. Due to the practical difficulties in using iron oxide nanoparticles for water treatment, these nanoparticles may be coated onto some supports. This paper focuses on the preparation of iron oxide nanoparticles coated sand by biological method using polysaccharide templates and chemical method i.e. sol-gel method. The synthesized particles were characterized using energy dispersive spectroscopy (EDS), scanning electron microscope (SEM) and powder X-ray diffraction analysis (PXRD). From EDS analysis the highest percentage coating of iron on the sand surface was obtained for the iron oxide nanoparticles coated sand synthesized using chitosan templates. The PXRD analysis revealed the crystallite size of the synthesized particles as 42.8nm. The SEM image showed the presence of almost spherical shaped particles on the sand surface and the coating was discontinuous.

Continuous Flow Preparation of Iron Oxide Nanoparticles Supported on Porous Silicates

AbstractA simple, innovative, and efficient continuous flow methodology for the direct preparation of supported nanoparticles on porous materials by using metal precursor solution flowing through heated packed‐bed reactors containing the support material has been developed. The effects of the flow rate of the precursor solution, temperature, and nature of the support material and metal loading have been investigated. Results indicated that optimum conditions comprised short residence times (with typical flow rates of 0.5 mL min−1 and below) under mild heating (100 °C) to achieve optimum materials in terms of nanoparticle size and structure and catalytic activity. The support was found to have a remarkable effect on both loading and distribution and agglomeration of nanoparticles in the system, with a previously reported Fe/Al synergy also observed in the prepared nanomaterials, which led to optimum results.

In situ preparation of iron oxide nanoparticles in natural hydroxyapatite/chitosan matrix for bone tissue engineering application

Magnetic materials inside bone scaffolds are known to be a promoting factor for bone healing especially when the therapy is accompanied by application of external magnetic stimulation. In this study we employed a new route to synthesize iron oxide nanoparticles inside hydroxyapatite/chitosan bone scaffolds. Hydroxyapatite and chitosan are both natural compounds and were prepared from bovine cortical bone and shrimp shell, respectively. The morphology and composition of the synthesized materials were characterized employing scanning electron microscopy and FTIR spectroscopy. The iron oxide mean particle size inside the scaffold matrix was estimated to be in the range of 10–40nm by particle size analyzer and transmission electron microscopy. The X-ray powder diffraction pattern indicated that the magnetite crystal size was about 23.5nm. Magnetic measurements specified that the saturated magnetic intensity (Ms) was approximately 3.04emu/g and the coercive force was 128.39Oe. The results revealed that the as-prepared magnetite was super-paramagnetic.

In vivo monitoring of rat macrophages labeled with poly(l-lysine)-iron oxide nanoparticles.

Coprecipitation of FeCl2 and FeCl3 with aqueous ammonia was used to prepare iron oxide nanoparticles dispersible in aqueous medium. Oxidation of the particles with sodium hypochlorite then yielded maghemite (γ-Fe2 O3 ) nanoparticles which were coated with two types of coating -d-mannose or poly(l-lysine) (PLL) as confirmed by FTIR analysis. The particles were <10 nm according to transmission electron microscopy. Their hydrodynamic particle size was ∼180 nm (by dynamic light scattering). The d-mannose-, PLL-coated, and neat γ-Fe2 O3 particles as well as commercial Resovist® were used to label rat macrophages. The viability and contrast properties of labeled macrophages were compared. PLL-coated γ-Fe2 O3 nanoparticles were found optimal. The labeled macrophages were injected to rats monitored in vivo by magnetic resonance imaging up to 48 h. Transport of macrophages labeled with PLL-γ-Fe2 O3 nanoparticles in rats was confirmed. Tracking of macrophages using the developed particles can be used for monitoring of inflammations and cell migration in cell therapy.

BIOPROCESS VARIABLES OF MAGNETITE NANOPARTICLES USING MODIFIED MODERN BHASMIKARAN METHOD

A BSTRA C T Lauha bhasma or iron oxide is a well known ancient form of Ayurvedic medicine for treating diseases such as anemia and jaundice since seventh century BC. The preparation generally involves a tedious long process of conversion of raw materials into ash or bhasma for this purpose. In this paper, a novel and modern form of Ayurvedic method has been used to prepare iron oxide nanoparticles which is both cost effective and eco-friendly. The particles were synthesized through multiple filtration and calcination steps resulting in fine powders which were then analyzed through XRD, TEM and VSM for their structural, morphological and magnetic properties which showed a small transition from hematite phase to magnetic magnetite phase post to the final filtration technique. Keyword: Ayurveda, Lauha bhasma, Iron oxide nano particles.

Synthesis of maghemite (γ-Fe2O3) nanoparticles by thermal-decomposition of magnetite (Fe3O4) nanoparticles

In this research work, we prepared γ-Fe2O3 nanoparticles by thermal-decomposition of Fe3O4. The Fe3O4 nanoparticles were synthesized via co-precipitation method at room temperature. This simple, soft and cheap method is suitable for preparation of iron oxide nanoparticles (γ-Fe2O3; Fe3O4). The samples were characterized by X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR), transmission electron microscopy (TEM), vibrating sample magnetometer and differential scanning calorimeter (DSC). The XRD and FT-IR results indicated the formation of γ-Fe2O3 and Fe3O4 nanoparticles. The TEM images showed that the γ-Fe2O3 and Fe3O4 were spherical, and their size was 18 and 22 nm respectively. Magnetic properties have been measured by VSM at room temperature. Hysteresis loops showed that the γ-Fe2O3 and Fe3O4 nanoparticles were super-paramagnetic.

Preparation of iron oxide nanoparticles stabilized with biomolecules: Experimental and mechanistic issues

Nanoparticles (NPs) with magnetic properties based on magnetite (Fe3O4, MAG) modified with oleic acid (OA), chitosan (CS) and bovine serum albumin (BSA) have been prepared. A versatile method of synthesis was employed, involving two steps: (i) co-precipitation of MAG; and (ii) nanoprecipitation of macromolecules on as-formed MAG NPs. Experimental variables have been explored to determine the set of conditions that ensure suitable properties of NPs in terms of their size, functionality and magnetic properties. It was found that the presence of OA in Fe+2/Fe+3 solutions yields MAG NPs with lower aggregation levels, while increasing initial amounts of OA may change the capability of NPs to disperse in aqueous or organic media by modifying the stabilization mechanism. Incorporation of CS was verified through Fourier transform IR spectroscopy. This biopolymer stabilizes NPs by electrostatic repulsions leading to stable ferrofluids and minimal fraction of recoverable solid NPs. BSA was successfully added to NP formulations, increasing their functionality and probably their biocompatibility. In this case too stable ferrofluids were obtained, where BSA acts as a polyelectrolyte. From the proposed methodology it is possible to achieve a wide range of NPs magnetically active intended for several applications. The required properties may be obtained by varying experimental conditions.