Functionalized Magnetite Nanoparticles Research Articles

New Way to Produce Magnetite Nanoparticles at Low Temperature

This work reports a simple process for preparation of stable and uniform magnetite nanoparticles (Fe3O4) at low temperature. The method is supported in three single steps and provides low-sized functionalized magnetite nanoparticles at lower temperatures than the obtained by similar methods. The samples have been characterized by x-ray diffraction (XRD), Fouriertransform infrared spectroscopy (FT-IR), transmission electron microscopy (TEM), and vibrating sample magnetometry (VSM), where it shows the nature of the nanoparticles. This study reveals that these nanoparticles are spherical in shape and have an average size of 30 nm, they present a super-paramagnetic behavior, and IR spectra show the group of N-monosubstituted amides, CO-NH in the cover of the superparamagnetic nanoparticles which avoids their agglomeration..

Citrate modified β-cyclodextrin functionalized magnetite nanoparticles: a biocompatible platform for hydrophobic drug delivery

Water dispersible, β-cyclodextrin functionalized, magnetite nanoparticles are shown to be suitable for the delivery of the hydrophobic drug curcumin, with possible multifunctional applications.

Pushing the surface-enhanced Raman scattering analyses sensitivity by magnetic concentration: A simple non core–shell approach

A simple and accessible method for molecular analyses down to the picomolar range was realized using self-assembled hybrid superparamagnetic nanostructured materials, instead of complicated SERS substrates such as core–shell, surface nanostructured, or matrix embedded gold nanoparticles. Good signal-to-noise ratio has been achieved in a reproducible way even at concentrations down to 5×10−11M using methylene blue (MB) and phenanthroline (phen) as model species, exploiting the plasmonic properties of conventional citrate protected gold nanoparticles and alkylamine functionalized magnetite nanoparticles. The hot spots were generated by salt induced aggregation of gold nanoparticles (AuNP) in the presence of those analytes. Then, the aggregates of AuNP/analyte were decorated with small magnetite nanoparticles by electrostatic self-assembly forming MagSERS hybrid nanostructured materials. SERS peaks were enhanced up to 100 times after magnetic concentration in a circular spot using a magnet in comparison with the respective dispersion of the nanostructured material.

Kinetic and equilibrium study of selenium removal from wastewater in mag-molecular process

In the present study, a mag-molecule was fabricated by functionalizing of silica-coated magnetite nanoparticles (MNPs) with 3-aminopropyl triethoxysilane (APTES). The amine functional group on surface of the particles was detected using Fourier transmission infrared spectroscopy technique. The morphology and dispersion of the functionalized magnetite nanoparticles (FMNPs) were observed through SEM images. The X-ray diffraction pattern illustrated the cubic crystal structure of MNPs with 28.79nm of diameter which was almost identical with SEM images. The kinetic of adsorption was studied and pseudo-second-order represented the best fitting to the experimental data. In addition, chemical adsorption for MNPs and physical adsorption for FMNPs were diagnosed applying the Elovich model. The Freundlich model showed a better result for MNPs, which demonstrates a multilayer adsorption on heterogeneous surface, while the Langmuir model was well fitted to FMNPs data, which indicates a homogeneous adsorption at one layer. Continuous system was performed in the fixed-bed column and the obtained results showed the efficiency of continuous system in selenium (Se) removal. The breakthrough curves were provided in three different flow rates and two bed depths and the results showed that the Thomas model can be a promising model for prediction of column performance. The Yoon–Nelson model also represented an acceptable conformation to experimental data. The time required to reach outlet concentration to 50% of initial concentration was calculated by Yoon–Nelson model, and the results were found to be in agreement with the experiments.

MAPLE fabrication of thin films based on kanamycin functionalized magnetite nanoparticles with anti-pathogenic properties

In this study we aimed to evaluate the biocompatibility and antimicrobial activity of kanamycin functionalized 5nm-magnetite (Fe3O4@KAN) nanoparticles thin films deposited by Matrix Assisted Pulsed Laser Evaporation (MAPLE) technique. A laser deposition regime was established in order to stoichiometrically transfer Fe3O4@KAN thin films on silicone and glass substrates. Morphological and physico-chemical properties of powders and coatings were characterized by XRD, TEM, SEM, AFM and IR microscopy (IRM). Our nanostructured thin films have proved efficiency in the prevention of microbial adhesion and mature biofilms development as a result of antibiotic release in its active form. Furthermore, kanamycin functionalized nanostructures exhibit a good biocompatibility, both in vivo and in vitro, demonstrating their potential for implants application. This is the first study reporting the assessment of the in vivo biocompatibility of a magnetite-antimicrobial thin films produced by MAPLE technique.

Synthesis, characterization and in vitro study of biocompatible cinnamaldehyde functionalized magnetite nanoparticles (CPGF Nps) for hyperthermia and drug delivery applications in breast cancer.

Cinnamaldehyde, the bioactive component of the spice cinnamon, and its derivatives have been shown to possess anti-cancer activity against various cancer cell lines. However, its hydrophobic nature invites attention for efficient drug delivery systems that would enhance the bioavailability of cinnamaldehyde without affecting its bioactivity. Here, we report the synthesis of stable aqueous suspension of cinnamaldehyde tagged Fe3O4 nanoparticles capped with glycine and pluronic polymer (CPGF NPs) for their potential application in drug delivery and hyperthermia in breast cancer. The monodispersed superparamagnetic NPs had an average particulate size of ∼20 nm. TGA data revealed the drug payload of ∼18%. Compared to the free cinnamaldehyde, CPGF NPs reduced the viability of breast cancer cell lines, MCF7 and MDAMB231, at lower doses of cinnamaldehyde suggesting its increased bioavailability and in turn its therapeutic efficacy in the cells. Interestingly, the NPs were non-toxic to the non-cancerous HEK293 and MCF10A cell lines compared to the free cinnamaldehyde. The novelty of CPGF nanoparticulate system was that it could induce cytotoxicity in both ER/PR positive/Her2 negative (MCF7) and ER/PR negative/Her2 negative (MDAMB231) breast cancer cells, the latter being insensitive to most of the chemotherapeutic drugs. The NPs decreased the growth of the breast cancer cells in a dose-dependent manner and altered their migration through reduction in MMP-2 expression. CPGF NPs also decreased the expression of VEGF, an important oncomarker of tumor angiogenesis. They induced apoptosis in breast cancer cells through loss of mitochondrial membrane potential and activation of caspase-3. Interestingly, upon exposure to the radiofrequency waves, the NPs heated up to 41.6°C within 1 min, suggesting their promise as a magnetic hyperthermia agent. All these findings indicate that CPGF NPs prove to be potential nano-chemotherapeutic agents in breast cancer.

Effect of functionalized magnetite nanoparticles and diaminoxanthone on the curing, thermal degradation kinetic and corrosion property of diglycidyl ether of bisphenol A-based epoxy resin

To prepare a high-performance epoxy resin with excellent thermal, chemical and corrosion stability, diaminoxanthone (DAX) was used to cure diglycidylether of bisphenol-A (DGEBA)-based epoxy resin and blend of DGEBA with functionalized Fe3O4 nanoparticles. Kinetic parameters of curing and thermal degradation of epoxy resin systems were estimated by differential scanning calorimetry (DSC) and thermogravimetric analysis (TGA), respectively. The 10% weight loss temperature has been increased from 340 °C to 366 °C and there was an increase in the char yield from 32.6% to 45.3% for the above systems. The corrosion performance of epoxy coated carbon steel was examined by potentiodynamic polarization, along with immersion test in 1.0 mol/L HCl solution. The results showed that epoxy resins cured with DAX had low tendency to corrosion. In addition, the cured epoxy resin containing 10% Fe3O4 had higher anticorrosion activity than bare DGEBA system. The results showed that functionalized Fe3O4 nanoparticles enhanced char formation and improved the thermal stability as well as anticorrosion activity of the resin.

Adsorption of vanadium(V) from acidic solutions by using octylamine functionalized magnetite nanoparticles as a novel adsorbent

Adsorption of vanadium(V) from acidic solutions was investigated by using octylamine functionalized magnetite nanoparticles as a novel adsorbent of vanadium. Batch experiments were conducted to determine the effects of initial pH, nanoparticles to octylamine weight ratio, amount of adsorbent, stirring time and initial vanadium(V) concentration in aqueous solution on adsorption efficiency. The adsorption was highly pH dependent, and the optimal pH was 3.2. The weight ratio of magnetite nanoparticles to octylamine was studied in optimum pH, and the best result was 3 : 2. More than 88% of vanadium(V) in solution was removed by 38.4 mg of adsorbent. In kinetics studies, the adsorption equilibrium could be achieved within 10minutes, and the experimental data were well fitted by the pseudosecond-order model. Comparison of Langmuir and Freundlich isotherm models indicated a better fit of Langmuir model to the adsorption of vanadium(V) and the mono-layer adsorption capacity for vanadium(V) was 25.707 mg g−1.

A Novel Potentiometric Detection Strategy for the Determination of Amlodipine Besylate Based on Functionalized Particles

AbstractA novel potentiometric strategy based on functionalized magnetite nanoparticles and microparticles were compared with the classical potentiometric strategy. This strategy provided nano‐ and microsized particles that were highly dispersed and coated with ionophore and plasticizer to promote an in situ cooperative ion‐pairing interaction between the ionophore and the analyte present in inner solution of sensor membrane, compared to the classical technique. Three amlodipine (AML) sensors were constructed using functionalized nanoparticles in sensor 1; microparticles in sensor 2, as ionophores, and the polymeric membrane ionophoric property in sensor 3.

Adsorption of U(VI) from aqueous solution by Triocthylamine (TOA) functionalized magnetite nanoparticles as a novel adsorbent

Adsorption of U (VI) from aqueous solutions was investigated using magnetically assisted chemical separation (MACS) process. In the present study, Triocthylamine (TOA) functionalized magnetite nanoparticles (TOAFMNPs) were applied as a novel adsorbent for adsorption of U (VI) from aqueous solutions. The effects of initial pH, Triocthylamine to magnetite nanoparticles weight ratio, amount of adsorbent, stirring time and initial U(VI) concentration on U(VI) adsorption efficiency were investigated by batch experiments. The adsorption of U(VI) using this adsorbent was pH dependent, and the optimal pH was 5.5. In kinetics studies, the adsorption equilibrium can be reach within 20 min., and the experimental data were well fitted by the pseudo-second-order model. The highest value of U(VI) adsorption (93.8%) was achieved in optimum conditions. The Langmuir isotherm model correlates well with the U(VI) adsorption equilibrium data for the concentration range 10-80 mg/l. The maximum U(VI) adsorption capacity onto adsorbent was 27.5 mg/g at room temperature. Present study suggests that TOAFMNPs could be employed as a potential adsorbent for U(VI) adsorption, and also could provide a simple and fast separation method for removal of U(VI) ion from solutions

Effect of solvent exchange on the stability of sterically functionalized magnetite nanoparticles in poly(methyl methacrylate) solutions and resulting spray dried composites

In this study highly filled nanoparticle–polymer composites consisting of the polymer poly(methyl methacrylate) and magnetite nanoparticles are synthesized via the solution and spray drying method. The synthesis process is carried out for two different solvents, dichloromethane and ethyl acetate, and the resulting suspensions and composites are compared to each other. The preparation of the composites consists of the following steps: First the magnetite nanoparticles are precipitated in an aqueous phase. In the next step the nanoparticles are coated with ricinoleic acid for stabilization and are transferred to the organic solvent dichloromethane. In a rotating evaporator the solvent dichloromethane is exchanged with ethyl acetate. Finally, the nanoparticles in the respective solvent and dissolved polymer are mixed and spray dried.The stability of the nanoparticle suspensions is characterized using thermogravimetric and photometric analyses. The specific surface of spray-dried composites is determined via BET measurements and the distribution of the nanoparticles is assessed with BSE-SEM imaging and laser diffraction.The stability of the nanoparticles is independent of the examined solvents. Both solvents provide a homogeneous distribution of nanoparticles in the composite at high filler concentrations.

Magnetic scaffolds of polycaprolactone with functionalized magnetite nanoparticles: physicochemical, mechanical, and biological properties effective for bone regeneration

Novel nanocomposite magnetic scaffolds demonstrated excellent bone cell responses.

Catechol-hydrazone conjugates for the rapid functionalization of magnetite nanoparticles with cell targeting groups

ABSTRACTThe condensation of hydrazides with aldehydes has been found to be a simple and rapid method for synthesizing catechol-terminated coating reagents for magnetite nanoparticles. This approach allowed the production of biotin- and polyethylene glycol-functionalized nanoparticles, whose interaction with 3T3 fibroblast cells has been assessed. The cellular location of these nanoparticles was imaged by fluorescence microscopy, which was made possible by co-coating with a porphyrin-catechol conjugate. Images show significant interactions between biotinylated nanoparticles and 3T3 fibroblasts, but those with a polyethylene glycol coating did not interact.

Preparation of Carboxyl Group Functionalized Magnetite Nanoparticles with High Magnetization

Preparation of Carboxyl Group Functionalized Magnetite Nanoparticles with High Magnetization

Preparation and characterization of flexible polyurethane foam nanocomposites reinforced by magnetic core-shell Fe3O4@APTS nanoparticles

Novel magnetic polyurethane flexible foam nanocomposites were synthesized by incorporation of aminopropyltriethoxysilane (APTS) functionalized magnetite nanoparticles (MNPs) via one-shot method. The functionalized MNPs (Fe3O4@APTS) were synthesized by co-precipitation of the Fe2+ and Fe3+ with NH4OH and further functionalization with APTS onto the surface of MNPs by sol–gel method. The magnetic core-shell NPs were used up to 3.0 % in the foam formulation and the magnetic nanocomposites prepared successfully. The results of thermogravimetric analysis (TGA) showed an increasing in thermal stability of polyurethane nanocomposite foam at initial, 5 and 10 %, and maximum thermal decomposition temperatures by incorporation of Fe3O4@APTS. In addition SEM images revealed the uniformity of the foam structures and decreasing in pore sizes. Furthermore, VSM result showed super paramagnetic behavior for Fe3O4@APTS-PU nanocomposites.

Biohybrid Nanostructured Iron Oxide Nanoparticles and Satureja hortensis to Prevent Fungal Biofilm Development

Cutaneous wounds are often superinfected during the healing process and this leads to prolonged convalescence and discomfort. Usage of suitable wound dressings is very important for an appropriate wound care leading to a correct healing. The aim of this study was to demonstrate the influence of a nano-coated wound dressing (WD) on Candida albicans colonization rate and biofilm formation. The modified WD was achieved by submerging the dressing pieces into a nanofluid composed of functionalized magnetite nanoparticles and Satureja hortensis (SO) essential oil (EO). Chemical composition of the EO was established by GC-MS. The fabricated nanostructure was characterized by X-ray Diffraction (XRD), Transmission Electron Microscopy (TEM), Differential Thermal Analysis (DTA) and Fourier Transform-Infrared Spectroscopy (FT-IR). The analysis of the colonized surfaces using (Scanning Electron Microscopy) SEM revealed that C. albicans adherence and subsequent biofilm development are strongly inhibited on the surface of wound dressing fibers coated with the obtained nanofluid, comparing with regular uncoated materials. The results were also confirmed by the assay of the viable fungal cells embedded in the biofilm. Our data demonstrate that the obtained phytonanocoating improve the resistance of wound dressing surface to C. albicans colonization, which is often an etiological cause of local infections, impairing the appropriate wound healing.

Removal and preconcentration of lead(II), cadmium(II) and chromium(III) ions from wastewater samples using surface functionalized magnetite nanoparticles

The potential removal and preconcentration of lead(II), cadmium(II), and chromium(III) ions from wastewaters were investigated and explored. Magnetite nanoparticles were chemically modified with p-nitro aniline. The aniline-coated magnetite nanoparticles (ANMNPs) were fully characterized by FT-IR, XRD, SEM, and TEM measurements. Batch studies were performed to address various experimental parameters for the removal and determination of these ions. ANMNPs showed high tendency to investigated metal ions, in this order: Cr(III) > Cd(II) > Pb(II), owing to the strong contribution of surface loaded aniline. The potential applications of ANMNPs adsorbent for removal and preconcentration of Pb(II), Cr(III), and Cd(II) from wastewaters as well as drinking tap water samples were successfully accomplished giving recovery values of (98–101 %), without any noticeable interference of the wastewater or drinking tap water matrices.

T-Cell Receptor Repertoires of Tumor-Infiltrating Lymphocytes After Hyperthermia Using Functionalized Magnetite Nanoparticles

Accumulating evidence has indicated that hyperthermia using magnetite nanoparticles induces antitumor immunity. This study investigated the diversity of T-cell receptors (TCRs) in tumor-infiltrating lymphocytes after hyperthermia using magnetite nanoparticles. Functionalized magnetite nanoparticles, N-propionyl-4-S-cysteaminylphenol (NPrCAP)/magnetite, were synthesized by conjugating the melanogenesis substrate NPrCAP with magnetite nanoparticles. NPrCAP/magnetite nanoparticles were injected into B16 melanomas in C57BL/6 mice, which were subjected to an alternating magnetic field for hyperthermia treatment. Enlargement of the tumor-draining lymph nodes was observed after hyperthermia. The TCR repertoire was restricted in tumor-infiltrating lymphocytes, and expansion of Vβ11(+) T cells was preferentially found. DNA sequences of the third complementaritydetermining regions revealed the presence of clonally expanded T cells. These results indicate that the T-cell response in B16 melanomas after hyperthermia is dominated by T cells directed toward a limited number of epitopes and that epitope-specific T cells frequently use a restricted TCR repertoire.

Efficient surface functionalization of wound dressings by a phytoactive nanocoating refractory to Candida albicans biofilm development

The present study reports the fabrication and characterization of a novel nanostructured phyto-bioactive coated rayon/polyester wound dressing (WD) surface refractory to Candida albicans adhesion, colonization and biofilm formation, based on functionalized magnetite nanoparticles and Anethum graveolens (AG) and Salvia officinalis (SO) essential oils (EOs). TEM, XRD, TGA, FT-IR were used for the characterization of the fabricated nanobiocoated WDs. Using magnetic nanoparticles for the stabilization and controlled release of EOs, the activity of natural volatile compounds is significantly enhanced and their effect is stable during time. For this reason the nanobiocoated surfaces exhibited a longer term anti-biofilm effect, maintained for at least 72 h. Besides their excellent anti- adherence properties, the proposed solutions exhibit the advantage of using vegetal natural compounds, which are less toxic and easily biodegradable in comparison with synthetic antifungal drugs, representing thus promising approaches for the development of successful ways to control and prevent fungal biofilms associated infections.

IMPROVEMENT OF THE PHOTOPHYSICAL PARAMETERS OF ZINC OCTACARBOXY PHTHALOCYANINE UPON CONJUGATION TO MAGNETIC NANOPARTICLES

Magnetic nanoparticles (MNPs) comprising magnetite (Fe3O4) were functionalized with 3-aminopropyl-triethoxysilane forming amino functionalized magnetite nanoparticles (AMNPs). The amino group allows for conjugation with zinc octacarboxyphthalocyanine ( ZnOCPc ) via the carboxyl group to form an amide bond. Transmission electron microscopy showed a change in morphology after conjugation. The covalent linkage of AMNPs to ZnOCPc has shown improvements in the photophysical behavior of the Pc in the presence of the MNP, increasing the triplet quantum yield (ΦT), singlet oxygen quantum yield (ΦΔ), triplet lifetime (τT) and singlet oxygen lifetime (τΔ) of the ZnOCPc and thus improving the efficiency of the ZnOCPc as a photosensitizer.