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Ferrite Nanoparticles (ferrite + nanoparticle)

Distribution by Scientific Domains

Polymers and Materials Science	33%
Physics and Astronomy	33%

Selected Abstracts

Development of a Quadruple Imaging Modality by Using Nanoparticles

CHEMISTRY - A EUROPEAN JOURNAL, Issue 37 2009
Won Hwang
Abstract The combination of nanotechnology with molecular imaging has great potential for the development of diagnostics and therapeutics, and multimodal imaging enables versatile applications from cell tracking in animals to clinical applications. Herein, we report a multimodal nanoparticle imaging system that is capable of concurrent fluorescence, bioluminescence, bioluminescence resonance energy transfer (BRET), positron emission tomography (PET) and magnetic resonance (MR) imaging in vivo. A cobalt,ferrite nanoparticle surrounded by rhodamine (MF) was conjugated with luciferase (MFB) and p -SCNbnNOTA (2-(4-isothiocyanatobenzyl)-1,4,7-triazacyclonane-1,4,7-triacetic acid) followed by 68GaCl3 (magnetic-fluorescent-bioluminescent-radioisotopic particle, MFBR). Confocal microscopy revealed good transfection efficiency of MFB into cells and BRET was also observed in MFB. A good correlation among rhodamine, luciferase, and 68GaCl3 was found in MFBR, and the activities of each imaging modality increased dose-dependently with the amount of MFBR in the C6 cells. In vivo optical images were acquired from the thighs of mice after intramuscular and subcutaneous injections of MFBR-laden cells. MicroPET and MR images showed intense radioactivity and ferromagnetic intensities with MFBR-laden cells. The multimodal imaging strategy could be used as potential imaging tools to track cells. [source]

Inorganic Nanoparticles for MRI Contrast Agents

ADVANCED MATERIALS, Issue 21 2009
Hyon Bin Na
Abstract Various inorganic nanoparticles have been used as magnetic resonance imaging (MRI) contrast agents due to their unique properties, such as large surface area and efficient contrasting effect. Since the first use of superparamagnetic iron oxide (SPIO) as a liver contrast agent, nanoparticulate MRI contrast agents have attracted a lot of attention. Magnetic iron oxide nanoparticles have been extensively used as MRI contrast agents due to their ability to shorten T2* relaxation times in the liver, spleen, and bone marrow. More recently, uniform ferrite nanoparticles with high crystallinity have been successfully employed as new T2 MRI contrast agents with improved relaxation properties. Iron oxide nanoparticles functionalized with targeting agents have been used for targeted imaging via the site-specific accumulation of nanoparticles at the targets of interest. Recently, extensive research has been conducted to develop nanoparticle-based T1 contrast agents to overcome the drawbacks of iron oxide nanoparticle-based negative T2 contrast agents. In this report, we summarize the recent progress in inorganic nanoparticle-based MRI contrast agents. [source]

Composition-Size Effects in Nickel,Zinc Ferrite Nanoparticles Prepared by Aqueous Coprecipitation

JOURNAL OF THE AMERICAN CERAMIC SOCIETY, Issue 4 2008
Brian T. Naughton
Nickel,zinc ferrite nanoparticles across the solid solution range, Ni1,xZnxFe2O4, from nickel ferrite to zinc ferrite were prepared by aqueous precipitation of mixed nitrate solutions at the same pH of 12.3. There is a linear relationship between the nanoparticle diameter and composition, decreasing with increasing zinc concentration across the solid solution. The nanoparticles are highly resistant to coarsening and some of them are faceted, suggesting that they are close to thermodynamic equilibrium. Measurements of the surface charge density of the nanoparticles, based on simultaneous conductimetric and potentiometeric titration, are presented as a function of composition for the zinc-rich compositions. A trend exists between the surface charge density and the zinc concentration, suggesting that they may be stabilized by charge. [source]

Microwave dielectric properties of NiFe2O4 nanoparticles ferrites

MICROWAVE AND OPTICAL TECHNOLOGY LETTERS, Issue 6 2007
C. P. L. Rubinger
Abstract Nickel ferrite (NiFe2O4) was synthesized by the micelles mixing method, using lyophilized coconut oil. The method leads to the formation of ferrite nanoparticles. Nickel ferrite was prepared in coconut oil suspension and annealed during 4 h, at 400, 600, 800, 1000, and 1200°C. The X-ray diffraction (XRD) was applied to investigate the nanoparticle size dependence on the annealing temperature. Complex permittivity measurements were carried out in cavity resonators at 5.0 and 9.0 GHz, using the small perturbation theory. The main result is that the real part of the permittivity decreases with increasing annealing temperatures (3.6,2.4), while the imaginary part of the permittivity varies only for the lowest annealing temperatures, remaining low for the other samples (about 10,3). The X-ray diffractograms indicates that the nanoparticle size increase with annealing temperature, allowed the correlation between the nanoparticle size and the observed microwave dielectric response. © 2007 Wiley Periodicals, Inc. Microwave Opt Technol Lett 49: 1341,1343, 2007; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.22402 [source]

Synthesis of nickel,zinc ferrite nanoparticles in polyol: morphological, structural and magnetic studies

PHYSICA STATUS SOLIDI (A) APPLICATIONS AND MATERIALS SCIENCE, Issue 3 2006
Z. Beji
Abstract Nickel,zinc ferrite monodisperse nanoparticles are synthesized by forced hydrolysis in diethylenglycol. FC and ZFC susceptibility curves suggest that they present superparmagnetic behaviour with a blocking temperature between 63 and 15 K depending on the zinc content. The saturation magnetization of the nanocrystals at 5 K is very close to that of bulk materials, and very high compared to that of similar particles prepared by other chemical routes. High Resolution Transmission Electron Microscopy and In-field Mössbauer studies show clearly that these relatively high values are mainly due to: (i) the high crystalline quality of the particles and (ii) a cation distribution different from the classical distribution encountered in the bulk material. (© 2006 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source]

The preparation of MnZn-ferrite nanoparticles in a water/CTAB, 1-butanol/1-hexanol reverse microemulsion

PHYSICA STATUS SOLIDI (C) - CURRENT TOPICS IN SOLID STATE PHYSICS, Issue 12 2004

Abstract Manganese zinc ferrite nanoparticles were prepared using a precipitation in reverse microemulsion system consisting of hexadecyltrimethyl ammonium bromide (CTAB) as a surfactant, 1-butanol as a co-surfactant, 1-hexanol as an oil phase and an aqueous solution of metal sulfates. Tetramethyl ammonium hydroxide (TMAH) served as the precipitating agent. The influence of the microemulsion's composition on the nature of the spinel product was studied. The synthesized nanoparticles were characterized using transmission electron microscopy (TEM), X-ray diffractometry (XRD), specific surface area (BET) and magnetometry. (© 2004 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source]