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Magnetics, IEEE Transactions on

Issue 1 • Date Jan. 2013

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  • Front cover

    Publication Year: 2013 , Page(s): C1
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  • IEEE Transactions on Magnetics publication information

    Publication Year: 2013 , Page(s): C2
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  • Table of Contents

    Publication Year: 2013 , Page(s): 161 - 164
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  • Preface [Selected Papers from the 9th International Conference on the Scientific and Clinical Applications of Magnetic Carriers (MCC 2012)]

    Publication Year: 2013 , Page(s): 165
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  • Spatial SPION Localization in Liposome Membranes

    Publication Year: 2013 , Page(s): 166 - 171
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (3542 KB) |  | HTML iconHTML  

    Nanocarriers, including liposomes, offer great opportunities for targeted and controlled therapy. The development in this field has led to a large panel of drug delivery systems, which can be classified into 3 different nanovector generations. However, the success of such smart materials requires the control of a large variety of properties and parameters. Unfortunately, characterization at the nanoscale is often cumbersome and many methods are still being developed. Liposomes have been characterized by cryogenic electron microscopy (CryoTEM) for quite some time, also in combination with nanoparticles, in particular with superparamagnetic iron oxide nanoparticles (SPIONs) incorporated inside the liposomal membrane. CryoTEM, unlike classical TEM, maintains the native state of the liposomes. The quick freezing of the sample immobilizes particles and liposomes exactly at their position in the suspension. Therefore, localization information can be extracted from the images. However, data must be treated extremely carefully keeping in mind that 2-D projections of a 3-D object are observed. In this paper, we discuss the analysis of cryoTEM images of liposome-particle hybrids, including the estimation of the contrast transfer function (CTF) and electron dose, as well as the correct positioning of the sample holder and tomography for accurate localization. View full abstract»

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  • Comparison of Strain-Promoted Alkyne-Azide Cycloaddition With Established Methods for Conjugation of Biomolecules to Magnetic Nanoparticles

    Publication Year: 2013 , Page(s): 172 - 176
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    The preservation of the bioreactivity of antibodies and proteins by immobilization on the surface of magnetic nanoparticles is essential for particle targeting applications in diagnosis and therapy. Here we compare the conjugation of a model antibody and of streptavidin to the surface of biocompatible 100 nm magnetic starch nanoparticles by strain-promoted alkyne-azide cycloaddition (SPAAC) with the established carbodiimide and maleimide chemistry. Under our reaction conditions the bioreactivity of the immobilized antibody was about 28% for the random amide bond formation using carbodiimide chemistry, the bioreactivity increased to about 61% for bioorthogonal SPAAC and to about 90% for maleimide conjugation. The same order was found for the biotin binding capacity of streptavidin, that was conjugated to the magnetic nanoparticles with the same methods. The described analytical methods are a platform for further studies with improved bioorthogonal conjugation reactions, e.g. the strain-promoted alkyne-nitrone cycloaddition (SPANC). View full abstract»

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  • A Rapid Assay to Measure the Shielding of Iron Oxide Cores by the Particle Shell

    Publication Year: 2013 , Page(s): 177 - 181
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    The conjugation of magnetic nano- and microparticles with biomolecules and its analysis very often require a dense coating of the iron oxide to prevent any reaction with redox-sensitive molecules or ions. The shielding of the iron oxide cores in different types of magnetic particles was compared by rapid assays that are based on the analysis of redox reactions. The oxidation of cysteine to the corresponding cysteine disulfide in the presence of incompletely covered iron oxide was analyzed with Ellman's reagent. Similar results were obtained by analysis of the reduction of copper (II) to copper(I) by the magnetite containing particles under the conditions of the Bicinchoninic Acid (BCA) assay. We show the assay results for different commercially available magnetic particles in the size range of 20 nm to 30 μm and conclude that an incomplete coverage of the iron oxide cores requires the comparison with reference particles in redox-sensitive assays, e.g., for the characterization of the protein coating or of the density of functional groups on the particle surface. View full abstract»

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  • Droplet Microfluidics to Prepare Magnetic Polymer Vesicles and to Confine the Heat in Magnetic Hyperthermia

    Publication Year: 2013 , Page(s): 182 - 190
    Multimedia
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    In this work, we present two types of microfluidic chips involving magnetic nanoparticles dispersed in cyclohexane with oleic acid. In the first case, the hydrophobically coated nanoparticles are self-assembled with an amphiphilic diblock copolymer by a double-emulsion process in order to prepare giant magnetic vesicles (polymersomes) in one step and at a high throughput. It was shown in literature that such diblock copolymer W/O/W emulsion droplets can evolve into polymersomes made of a thin (nanometric) magnetic membrane through a dewetting transition of the oil phase from the aqueous internal cores usually leading to “acorn-like” structures (polymer excess) sticking to the membranes. To address this issue and greatly speed up the process, the solvent removal by evaporation was replaced by a “shearing-off” of the vesicles in a simple poly(dimethylsiloxane) chip designed to exert a balance between a magnetic gradient and viscous shear. In the second example, a simple oil-in-oil emulsion chip is used to obtain regular trains of magnetic droplets that circulate inside an inductor coil producing a radio-frequency magnetic field. We evidence that the heat produced by magnetic hyperthermia can be converted into a temperature rise even at the scale of nL droplets. The results are compared to heat transfer models in two limiting cases: adiabatic vs. dissipative. The aim is to decipher the delicate puzzle about the minimum size required for a tumor “phantom” to be heated by radio-frequency hyperthermia in a general scope of anticancer therapy. View full abstract»

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  • Fabrication of BioInspired Inorganic Nanocilia Sensors

    Publication Year: 2013 , Page(s): 191 - 196
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    In nature, microscale hair-like projections called cilia are used ubiquitously for both sensing and motility. In this paper, biomimetic nanoscale cilia arrays have been fabricated through templated growth of Co in anodized aluminum oxide. The motion of arrays of Co cilia was then detected using magnetic sensors. These signals were used to prove the feasibility of two types of sensors: flow sensors and vibration sensors. The flow sensors were tested in a microfluidic channel. They showed the ability to detect flows from 0.5 ml/min to 6 ml/min with a signal to noise (SNR) of 44 using only 140 μW of power and no amplification. The vibration sensors were tested using a shake table in the low earthquake-like frequency range of 1-5 Hz. The vibration response was a mW signal at twice the frequency of the shake table. View full abstract»

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  • Composition- and Phase-Controlled High-Magnetic-Moment Fe _{1 - {\rm x}} Co _{\rm x} Nanoparticles for Biomedical Applications

    Publication Year: 2013 , Page(s): 197 - 200
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    Fe-Co alloy nanoparticles are studied in this work of different composition condition. Fe1-xCox nanoparticles were synthesized by a physical method with well-developed crystal structure, uniform size, and high saturation magnetization. Their magnetic property is found to be a function of composition, which indicates successful control of the synthesis process. Exchange bias was found for Fe1-xCox core-oxide shell particles after natural oxidization in air. It was a result of interfacial coupling between Fe/Co and their oxides. The property of the surface oxide varies with composition and so does the coupling strength. Oxidation and interparticle interactions lead to much different magnetic response of nanoparticles compared to un-oxidized, non-interacting ones. View full abstract»

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  • Size Distribution and Magnetization Optimization of Single-Core Iron Oxide Nanoparticles by Exploiting Design of Experiment Methodology

    Publication Year: 2013 , Page(s): 201 - 207
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (1459 KB) |  | HTML iconHTML  

    The synthesis of single-core superparamagnetic iron oxide nanoparticles (SPIONs) via high temperature decomposition of the self-synthesized Fe(III)-oleate was studied by exploiting factorial design of experiment methodology to investigate the influence of Fe(III)-oleate concentration, reaction temperature and time, and heating rate on the particle core and hydrodynamic size distributions and magnetization. This approach enabled us to establish a reliable and reproducible protocol for the synthesis of monodisperse SPIONs with high magnetic performance. The structural and magnetic properties of SPIONs were characterized utilizing a variety of methods. By applying a multiple linear regression model, a simple and robust empirical growth model was found for the particle hydrodynamic diameter, presenting its dependencies on reaction temperature and time, and Fe(III)-oleate concentration. Having studied the thermal decomposition behavior of Fe(III)-oleate, the synthesis of highly monodisperse particles with a core size of ~ 12-14 nm and suitable magnetic properties was attributed to burst nucleation which is followed by a rapidly terminating growth. In contrast, the particles with a large primary core size of ~ 22-24 nm, crystallized via a gradual and low temperature nucleation accompanied by a slow growth and Ostwald ripening, show a broader or multi-modal size distribution with relatively poor magnetic performance. View full abstract»

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  • Magnetoviscous Effect in a Biocompatible Ferrofluid

    Publication Year: 2013 , Page(s): 208 - 212
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    The advancing development in biomedical applications of magnetic nanoparticles leads to an increasing demand for reliable data concerning the thermophysical properties of the ferrofluids used. For applications with a relation to the flow behavior of the nanoparticle suspensions-like, e.g., magnetic drug targeting-the understanding of the basic rheological properties of the fluids under the influence of magnetic fields is of general importance. In the ongoing work presented here a magnetite-based commercial ferrofluid featuring multi-domain cores with dextran as surfactant was investigated using rotational rheometry. The analysis includes flow curve as well as yield stress measurements and reveals the magnetoviscous effect of the fluid. It has been found that significant changes of viscosity and of the overall flow behavior are induced even at low magnetic field strengths. The detected effects and therefore the changing rheological behavior of the fluid under investigation should be taken into account for further improvement of biomedical applications as well as for the synthesis of biocompatible ferrofluids. View full abstract»

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  • Microwave Assisted Synthesis of Magnetically Responsive Composite Materials

    Publication Year: 2013 , Page(s): 213 - 218
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    One-pot, microwave-assisted synthesis of various types of magnetically responsive materials from non-magnetic precursors has been developed. The preparation is based on the microwave irradiation of the suspension of the treated material with iron(II) hydroxide prepared by alkalization of iron(II) sulfate. Submicrometer magnetic particles formed during the microwave treatment deposited on the surface of the treated materials in the form of individual particles and their aggregates. The prepared magnetically responsive materials have been used as adsorbents for xenobiotics removal and as carriers for enzymes immobilization. View full abstract»

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  • Synthesis of PEGylated Magnetic Nanoparticles With Different Core Sizes

    Publication Year: 2013 , Page(s): 219 - 226
    Cited by:  Papers (1)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (1828 KB) |  | HTML iconHTML  

    Tailoring the properties of superparamagnetic nanoparticles (MNPs) is essential for various nano-based biological applications. Having control over the properties of the MNPs permits a maximum flexibility. Starting from monodisperse iron oxide MNPs produced by thermal decomposition, we report on the optimization and characterization of a first and second seed mediated growth step by varying the surfactant amount and by optimizing the heating steps. We demonstrate the ability to gradually increase the size of crystalline MNPs from 6 over 9 to 12 nm with an improving monodispersity as demonstrated by Transmission Electron Microscopy, Dynamic Light Scattering and X-ray diffraction. The magnetic properties of the MNPs, studied by Vibrating Sample Magnetometry, were in concert with their size increase. We also show the functionalization of these particles with polyethylene glycolated silanes, to render the MNPs stable in water. Different characterization techniques, namely Transmission Electron Microscopy, Dynamic Light Scattering, Fourier-transform InfraRed, Thermo gravimetric analysis and X-ray Photoelectron Spectroscopy, confirmed the successful engraftment of the silanes on the MNP's surface. In conclusion, the proposed route of step-wise synthesis in combination with silane functionalization allows fine tuning the physical properties of iron oxide MNPs for applications in an aqueous environment. View full abstract»

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  • Measurement of Brownian and Néel Relaxation of Magnetic Nanoparticles by a Mixing-Frequency Method

    Publication Year: 2013 , Page(s): 227 - 230
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (809 KB) |  | HTML iconHTML  

    A detection scheme for both Brownian and Néel relaxation of magnetic nanoparticles (MNPs) is demonstrated by a mixing-frequency method in this paper. MNPs are driven into the saturation region by a low-frequency sinusoidal magnetic field. A high-frequency sinusoidal magnetic field is then applied to generate mixing-frequency signals that are highly specific to the Brownian relaxation of MNPs. These highly sensitive mixing-frequency signals from MNPs are picked up by a pair of balanced built-in detection coils. The relationship between MNPs' relaxation time and phase delays of the mixing-frequency signals behind the applied field is derived, and is experimentally verified. Magnetite MNPs with the core diameter of 35 nm are used for the measurement of Brownian relaxation, and Magnetite MNPs with the core diameter of 12 nm are used for the measurement of Néel relaxation. The results show that both Brownian and Néel relaxation depend on the magnetic offset field. This study provides an in-depth understanding of the relaxation mechanisms of MNPs. View full abstract»

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  • Magnetic Heating of Iron Oxide Nanoparticles and Magnetic Micelles for Cancer Therapy

    Publication Year: 2013 , Page(s): 231 - 235
    Cited by:  Papers (2)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (1459 KB) |  | HTML iconHTML  

    The inclusion of magnetic nanoparticles into block copolymer micelles was studied towards the development of a targeted, magnetically triggered drug delivery system for cancer therapy. Herein, we report the synthesis of magnetic nanoparticles and poly(ethylene glycol-b-caprolactone) block copolymers, and experimental verification of magnetic heating of the nanoparticles, self-assembly of the block copolymers to form magnetic micelles, and thermally-enhanced drug release. The semicrystalline core of the micelles melted at temperatures just above physiological conditions, indicating that they could be used to release a chemotherapy agent from a thermoresponsive polymer system. The magnetic nanoparticles were shown to heat effectively in high frequency magnetic fields ranging from 30-70 kA/m. Magnetic micelles also showed heating properties, that when combined with a chemotherapeutic agent and a targeting ligand could be developed for localized, triggered drug delivery. During the magnetic heating experiments, a time lag was observed in the temperature profile for magnetic micelles, likely due to the heat of fusion of melting of polycaprolactone micelle cores before bulk solution temperatures increased. Doxorubicin, incorporated into the micelles, released faster when the micelles were heated above the core melting point. View full abstract»

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  • Thermal Properties of Magnetic Nanoparticles Modified With Polyethylene Glycol

    Publication Year: 2013 , Page(s): 236 - 239
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (1212 KB) |  | HTML iconHTML  

    Magnetic fluids used in biomedicine have to be biocompatible and therefore the magnetic nanoparticles are modified by different biocompatible materials. In this work the magnetic nanoparticles Fe3O4 sterically stabilized by sodium oleate were prepared by coprecipitation method. Consequently they were modified with polyethylene glycol (PEG) of different molecular weights and different PEG to magnetite Fe3O4 feed weight ratios varying from 0.01 to 30 to produce biocompatible magnetic fluids (MFPEG). The morphology was observed by scanning electron microscopy. The magnetic nanoparticles coated with PEG showed almost spherical shape for all studied systems of MFPEG. Differential scanning calorimetry (DSC) was used to study the adsorption of PEG on magnetic nanoparticles and to determine the maximal amount of PEG adsorbed on the magnetic nanoparticles. The increasing PEG molecular weight leads to the decrease in maximal PEG/Fe3O4 feed weight ratio. In vitro toxicity of the magnetic fluids using cells of skin cancer of mice B16 was tested with the aim to confirm the biocompatibility of the prepared magnetic fluids. View full abstract»

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  • Self-Heating Temperature and AC Hysteresis of Magnetic Iron Oxide Nanoparticles and Their Dependence on Secondary Particle Size

    Publication Year: 2013 , Page(s): 240 - 243
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    Magnetic nanoparticles are expected to be used as hyperthermia agents. The mechanism of self-heating of the magnetic nanoparticles under an ac magnetic field is different according to their size. In this study, the temperature rise for the ac/dc hysteresis loops of magnetic nanoparticles were evaluated to clarify the contribution of the Néel and Brownian relaxations to heat dissipation. The samples were dextran-coated magnetic iron oxide nanoparticles of different hydrodynamic diameters (40, 54, and 86 nm), but the same primary diameter of 10 nm. From these diameters, the peak frequencies for the Brownian and Néel relaxations were calculated. The Néel relaxation time, determined by the primary particle size, is much shorter than the Brownian relaxation time for these samples. Although the Néel relaxation is dominant, the self-heating temperature rise of the 86 nm sample was higher than that of the 40 and 54 nm samples. These results suggest that the effect of the magnetic interaction between the nanoparticles depends on the hydrodynamic diameter. View full abstract»

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  • Tissue Model for the Study of Heat Transition During Magnetic Heating Treatment

    Publication Year: 2013 , Page(s): 244 - 249
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (706 KB) |  | HTML iconHTML  

    Heat can be induced within a tissue enriched with magnetic nanoparticles by exposing it to an alternating magnetic field. In this paper we examine the evaluation of the heat distribution and therefore the temperature development around such a heat source which can be suitable for magnetic heating treatment. We study the heat transfer from tissue enriched with magnetic nanoparticles to regions of no or minor enrichment of nanoparticles, particularly. The evaluation of the temperature distribution took place with the help of a tissue phantom. The phantom is composed of two concentric cylinders. The inner cylinder consists of a defined mixture of polyurethane gel and magnetic fluid. This cylinder represents tissue enriched with nanoparticles. The outer cylinder, which stands for pure tissue consists of polyurethane only. This tissue phantom has been exposed to an alternating magnetic field according to the protocol of the magnetic heating treatment. The temperature measurements were performed by thermocouples which are placed on defined positions. The experimentally obtained temperature data is the basis for a finite element method (FEM) simulation model. The FEM model allows the determination of heat transition from regions enriched with magnetic nanoparticles to regions with no or minor nanoparticle accumulation. View full abstract»

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  • Hyperthermic Effect in Suspension of Magnetosomes Prepared by Various Methods

    Publication Year: 2013 , Page(s): 250 - 254
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    The magnetic properties and hyperthermia effect were studied in solution of magnetosomes obtained by changing conditions during biomineralization of magnetotactic bacteria Magnetospirillum sp.AMB-1. It was shown that adding a higher amount of Wolfe's vitamin solution (WVS) or ferric quinate (FQ) cause increase of the mean diameter from 47 nm (normal condition) up to 52 nm and 58 nm respectively. As a consequence of this change the preparation conditions coercivity and Specific Absorption Rate (SAR) increased up to 20 Oe and 949 W/gFe for sample FQ, respectively. On the other hand the process of cultivation at the changed conditions markedly reduced the cultivation time. Also the isolated chains of magnetosome were shorter containing less amount of magnetosomes too. View full abstract»

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  • Potential Sources of Errors in Measuring and Evaluating the Specific Loss Power of Magnetic Nanoparticles in an Alternating Magnetic Field

    Publication Year: 2013 , Page(s): 255 - 262
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    Heat-generating magnetic nanoparticles suspensions are being explored in research and clinical settings as hyperthermia treatment for cancer or as adjuvant in established cancer therapies. In these applications it is essential to use low nanoparticle dosage to prevent any potential side effects including those associated with their accumulation in liver or spleen. Hence, developing particles with superior heating properties continues to remain an active area of research. Specific loss power (SLP), also referred to as specific absorption rate (SAR), represents the power dissipation per unit mass of magnetic nanoparticles in alternating magnetic fields. Accurate measurement of SLP is the key for understanding the parameters that control the heat generation rate, which is required to optimize these systems. However, at presents there are no standards for performing SLP measurements and no accepted calibration materials, making it difficult to compare the performance of various systems reported in literature. Previous work from this group discussed the effect of sample volume and geometry on the SLP data accuracy. In this study, additional analysis and experiments are carried out to investigate the effect of the power dissipation rate, the magnetic properties and the method for temperature slope calculation on the accuracy of the reported power density. Results indicate that when the same heating time is used, the volume at which heat losses become negligible decreases with decreasing sample heating rate. Furthermore, it is shown that for calculating initial temperature slope, a larger error occurs with a longer heating time and higher power level regardless of the curve fitting methods, hence, when power density or heating time increases, a higher order curve fitting (e.g., 2nd polynomial and exponential) is more desirable. In addition, when the magnetization of a nanoparticle suspension is low, the SLP is independent of the sample geometry. View full abstract»

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  • Anomalously High Specific Absorption Rate in Bioaffine Ligand-Coated Iron Oxide Nanoparticle Suspensions

    Publication Year: 2013 , Page(s): 263 - 268
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (1293 KB) |  | HTML iconHTML  

    Bioaffine ligand-coated iron oxide nanoparticles have been commonly utilized to target cancer cells and have potential for application in hyperthermia for cancer treatment. Hence, it is important to gain more understanding on their heat dissipation mechanisms to better optimize them for clinical treatments. Of particular importance is to determine the effect of biofunctional coating on the heat generation rate, especially when it is formed by relatively large molecules. In this context, the heat dissipation rate of magnetite nanoparticle coated with biotin and protein A was studied by comparing their theoretical and experimental specific absorption rate (SAR). The results suggest that the experimental SAR of both samples is higher than the SAR predicted based on experimental AC magnetic susceptibility, which takes into account magnetic losses only. The increase in SAR above predictions is attributed in part to additional friction loss associated with the partial rotation of large, asymmetric clusters of magnetite nanoparticles in alternating magnetic field. This hypothesis was verified by comparing the rate of temperature increase of nanoparticles embedded in hydrogel of different stiffness. View full abstract»

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  • Multicore Magnetic Nanoparticles for Magnetic Particle Imaging

    Publication Year: 2013 , Page(s): 269 - 274
    Save to Project icon | Click to expandQuick Abstract | PDF file iconPDF (1647 KB) |  | HTML iconHTML  

    Biocompatible magnetic nanoparticles are interesting tracers for diagnostic imaging techniques, including magnetic resonance imaging and magnetic particle imaging (MPI). Here, we will present our studies of the physical and especially magnetic properties of dextran coated multicore magnetic iron oxide nanoparticles, with promising high MPI signals revealed by magnetic particle spectroscopy (MPS) measurements. The Nanomag-MIP particles with a hydrodynamic diameter of 106 nm show an increase of the MPS amplitude by a factor of about two at the 3rd harmonic, as compared to Resovist. In particular, the signal improves progressively with the order of the harmonic, a prerequisite for better spatial resolution. To understand this behavior, we investigated the samples using quasistatic magnetization measurements yielding bimodal size distributions for both systems, and magnetorelaxometry providing the mean effective anisotropy constant. The mean effective magnetic diameter of the dominant larger size mode is 19 nm with a dispersion parameter of σ = 0.3 for Nanomag-MIP, and 22 nm with σ = 0.25 for Resovist. However, about 80% of the magnetic nanoparticles of Nanomag-MIP belong to this larger size mode whereas in Resovist only 30% do. The remaining Resovist particles are in the range of 5 nm, and, in practice, do not contribute to the MPI signal. View full abstract»

    Open Access
  • Cellular Uptake of Magnetic Nanoparticles Quantified by Magnetic Particle Spectroscopy

    Publication Year: 2013 , Page(s): 275 - 278
    Cited by:  Papers (1)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (708 KB) |  | HTML iconHTML  

    The quantification of magnetic iron oxide nanoparticles in biological systems (cells, tissues and organs) is of vital importance in the development of novel biomedical applications such as magnetofection, drug targeting or hyperthermia. Among several techniques established to detect iron in tissue, the recently developed technique of magnetic particle spectroscopy (MPS) provides signals that are specific for magnetic nanoparticles. MPS utilizes the non-linear response of an MNP sample to a strong sinusoidal excitation field of up to 25 mT amplitude and 25 kHz. We demonstrate the feasibility of this technique to quantify nanoparticle uptake in cells using a commercial magnetic particle spectrometer (Bruker BioSpin). View full abstract»

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  • Automated Fluorescence and Reflectance Coregistered 3-D Tissue Imaging System

    Publication Year: 2013 , Page(s): 279 - 284
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (741 KB) |  | HTML iconHTML  

    An automated system was developed to image the 3-D distribution of fluorescent magnetic nanoparticles in tissue samples. It enables easy measurement of magnetic nanoparticle distributions, for small and large tissue samples (currently up to a maximum size of 25 mm × 25 mm × 25 mm), in 3-D, with about 70 resolution in plane and 1 μm in the vertical direction. There is a linear correlation between particle concentration and fluorescence intensity, hence the system provides a quantitative measure of the nanoparticle distribution, but the tissue sample is destroyed during the imaging process. The system was demonstrated by measuring the particle distribution in rat ear and brain samples. View full abstract»

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Aims & Scope

IEEE Transactions on Magnetics publishes research in science and technology related to the basic physics and engineering of magnetism, magnetic materials, applied magnetics, magnetic devices, and magnetic data storage.

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Meet Our Editors

Editor-in-Chief
Pavel Kabos
National Institute of Standards and Technology