A5101984650- Metallic Glasses and Amorphous Alloys
- Magnetic properties of thin films
- Geomagnetism and Paleomagnetism Studies
- Characterization and Applications of Magnetic Nanoparticles
- Magnetic Properties and Applications
- Magnetic and Electromagnetic Effects
- Magnetic Properties of Alloys
- Theoretical and Computational Physics
- Magnetic Properties and Synthesis of Ferrites
- Nanoparticle-Based Drug Delivery
- Iron oxide chemistry and applications
- Planetary Science and Exploration
- X-ray Spectroscopy and Fluorescence Analysis
- Magnetic and transport properties of perovskites and related materials
- Geology and Paleoclimatology Research
- Shape Memory Alloy Transformations
- Multiferroics and related materials
- Microstructure and Mechanical Properties of Steels
- Copper Interconnects and Reliability
- Surface and Thin Film Phenomena
- Geochemistry and Elemental Analysis
- Surface Roughness and Optical Measurements
- Rare-earth and actinide compounds
- Heusler alloys: electronic and magnetic properties
- Metallurgical and Alloy Processes
University of the Basque Country
2015-2024
Fundación General
2019
Universidad de Oviedo
1998-2001
Ente Vasco de la Energía
1995
Magnetic nanoparticle-mediated hyperthermia is a very promising therapy for cancer treatment. In this field, superparamagnetic iron oxide nanoparticles have been commonly employed because of their intrinsic biocompatibility, but they present some limitations that restrict heating efficiency (specific absorption rate, SAR). Therefore, we investigated how tuning the size and shape these can be useful to enhance responses. Monodisperse crystalline synthesized by thermal decomposition in two...
<para xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> Various series of permalloy thin films were grown by dc-sputtering on Si (100) and glass substrates at room temperature different argon pressure values using a Fe<formula formulatype="inline"><tex Notation="TeX">$_{20}$</tex> </formula>Ni<formula Notation="TeX">$_{80}$</tex> </formula> target. The increase leads to decrease the Fe concentration in from 17 at.% 15 at.%, an root mean square...
Abstract Magnetotactic bacteria are aquatic microorganisms that internally biomineralize chains of magnetic nanoparticles (called magnetosomes) and use them as a compass. Here it is shown magnetotactic the strain Magnetospirillum gryphiswaldense present high potential hyperthermia agents for cancer treatment. Their heating efficiency or specific absorption rate determined using both calorimetric AC magnetometry methods at different field amplitudes frequencies. In addition, effect alignment...
We hereby present experimental and theoretical insights on the use of biomineralized magnetite nanoparticles, called magnetosomes, as heat nanoinductors in magnetic hyperthermia technique. The heating efficiency or specific absorption rate magnetosomes extracted from Magnetospirillum gryphiswaldense bacteria immersed water agarose gel, was directly determined hysteresis loops obtained at different frequencies field amplitudes. demonstrate that production can be predicted framework...
This study provides a guide to maximizing hysteretic loss by matching the design and synthesis of superparamagnetic nanoparticles desired hyperthermia application. The maximal heat release from magnetic environment depends on intrinsic properties (e.g. size, magnetization, anisotropy), extrinsic applied fields frequency, field strength). Often, biomedical application limits flexibility in setting many parameters nanoparticle size mobility, strength frequency). We show that core-shell...
Among iron oxide phases, magnetite (Fe3O4) is often the preferred one for nanotechnological and biomedical applications because of its high saturation magnetization low toxicity. Although there are several synthetic routes that attempt to reach nanoparticles (NPs), they usually referred as "IONPs" (iron NPs) due great difficulty in obtaining monophasic stoichiometric Fe3O4 phase. Added this problem common increase size/shape polydispersity when larger NPs (D > 20 nm) synthesized. An...
${\text{Fe}}_{x}{\text{Ag}}_{100\ensuremath{-}x}$ granular thin films, with $20\ensuremath{\le}x\ensuremath{\le}50$, have been prepared by the dc-magnetron sputtering deposition technique. With this technique we able to obtain samples comprising small Fe nanoparticles (2.5--3 nm) embedded in a Ag matrix, remaining their size practically constant increasing content. Their magnetic behavior has fully characterized dc measurements between 5--350 K. They revealed crossover collective of around...
<italic>Magnetospirillum gryphiswaldense</italic> is a microorganism with the ability to biomineralize magnetite nanoparticles, called magnetosomes, and arrange them into chain that behaves like magnetic compass.
Most studies on magnetic nanoparticle-based hyperthermia utilize iron oxide nanoparticles smaller than 20 nm, which are intended to have superparamagnetic behavior (SP-MNPs). However, the heating power of larger with non-fluctuating or fixed dipoles (F-MNPs) can be significantly greater that SP-MNPs if high enough fields (H > 15 mT) used. But synthesis single nanocrystals magnetite (Fe3O4) a regular shape and narrow size distribution devoid secondary phases remains challenge. Iron...
Local heat generation from magnetic nanoparticles (MNPs) exposed to alternating fields can revolutionize cancer treatment. However, the application of MNPs as anticancer agents is limited by serious drawbacks. Foremost among these are fast uptake and biodegradation cells unpredictable behavior when they accumulate within or around tissues. In fact, several studies have reported that heating power severely reduced in cellular environment, probably due a combination increased viscosity strong...
Aim The Specific Absorption Rate (SAR) is the key parameter to optimize effectiveness of magnetic nanoparticles in hyperthermia. AC magnetometry arises as a powerful technique quantify SAR by computing hysteresis loops' area. However, currently available devices produce quite limited field intensities, below 45mT, which are often insufficient obtain major loops and so more complete understandable magneticcharacterization. This limitation leads lack information concerning some basic...
The currently existing magnetic hyperthermia treatments usually need to employ very large doses of nanoparticles (MNPs) and/or excessively high excitation conditions (H × f > 1010 A/m s) reach the therapeutic temperature range that triggers cancer cell death. To make this anticancer therapy truly minimally invasive, it is crucial development improved chemical routes give rise monodisperse MNPs with saturation magnetization and negligible dipolar interactions. Herein, we present an innovative...
Multimodal contrast agents, which take advantage of different imaging modalities, have emerged as an interesting approach to overcome the technical limitations individual techniques. We developed hybrid nanoparticles comprising iron oxide core and outer gold spiky layer, stabilized by a biocompatible polymeric shell. The combined magnetic optical properties components provide required functionalities for resonance (MRI), surface-enhanced Raman scattering (SERS), fluorescence imaging....
Nanohyperthermia therapies have appeared as a promising alternative for the treatment of diverse cancer tumors. Multifunctional nanosystems offer step forward in these therapies. They harness more efficient and multistimuli hyperthermia low-dose application, well supplementary functions imaging, targeting, controlled release, sensing. Among them, Janus Au:Fe3O4 nanoparticles (JNPs) are highly versatile prominent example dual photo- magneto-thermia capabilities. To achieve highest...
We report a combined structural and magnetic study of the mineral core biomineralized by horse spleen ferritin three prokaryotic ferritin-like proteins: bacterial bacterioferritin from <italic>Escherichia coli</italic> archaeal <italic>Pyrococcus furiosus</italic>.
Magnetotactic bacteria synthesize a chain of magnetic nanoparticles, called magnetosome chain, used to align and swim along the geomagnetic field lines. In particular, Magnetospirillum gryphiswaldense biomineralize magnetite, Fe3O4. Growing this species in Co-supplemented medium, Co-doped magnetite is obtained, tailoring way properties chain. Combining structural techniques such as transmission electron microscopy, energy-dispersive x-ray spectroscopy, X-ray absorption near edge structure,...
Over the past few years, use of nanomagnets in biomedical applications has increased. Among others, magnetic nanostructures can be used as diagnostic and therapeutic agents cardiovascular diseases, to locally destroy cancer cells, deliver drugs at specific positions, guide (and track) stem cells damaged body locations regenerative medicine tissue engineering. All these rely on properties which are mostly determined by their anisotropy. Despite its importance, anisotropy individual is...
FeZrB(Cu) metallic glasses present the same Invar (like) properties as pure FeZr ones, in particular a large dependence of Curie temperature on pressure. Magnetic and M\"ossbauer measurements show decrease character boron concentration increases, with linear relationship between change per unit stress reciprocal itself. The influence is shown to greatly enhance weak itinerant ferromagnetism leading stronger ferromagnetic behavior. \textcopyright{} 1996 American Physical Society.