Browsing by Author "Garayo Urabayen, Eneko"
Now showing 1 - 14 of 14
Results Per Page
Sort Options
Publication Open Access Desarrollo de un Sistema de Instrumentación Virtual en LabView para la toma de medidas en muestras magnetorresistivas(2022) Pérez Arnedo, Imanol; Garayo Urabayen, Eneko; López Ortega, Alberto; Escuela Técnica Superior de Ingeniería Industrial, Informática y de Telecomunicación; Industria, Informatika eta Telekomunikazio Ingeniaritzako Goi Mailako Eskola TeknikoaLa magnetorresistencia es la propiedad por la cual la resistencia eléctrica de un material conductor se ve modificada por la presencia de un campo magnético. Este fenómeno posee múltiples aplicaciones como el desarrollo de diversos sensores, así como ha tenido un impacto decisivo en el desarrollo de las memorias magnéticas en computación. La caracterización del comportamiento magnetorresistivo de un material, por lo tanto, requiere medir cómo evoluciona el valor de su resistencia en función del campo magnético. Cuantificar este fenómeno precisa de la toma de múltiples medidas de diferentes magnitudes -con el correspondiente uso de diversos instrumentos de medida-, cuestión que complica su cálculo manual. Por ello, en este proyecto, se propone la automatización de un ensayo mediante LabVIEW con el que caracterizar el comportamiento magnetorresistivo de unas muestras experimentales, de tal forma que un ordenador se encargue del control de los instrumentos y el almacenamiento de las medidas tomadas por ellos. Posteriormente se propone otro programa desarrollado con LabVIEW para el análisis de los datos obtenidos en el ensayo.Publication Open Access Design, simulation, construction and characterization of a vibrant magnetic structure for its use in magnetostrictive energy harvesters(2022) Sotelo Aguirre, Daniel; Beato López, Juan Jesús; Garayo Urabayen, Eneko; Escuela Técnica Superior de Ingeniería Industrial, Informática y de Telecomunicación; Industria, Informatika eta Telekomunikazio Ingeniaritzako Goi Mailako Eskola TeknikoaEl trabajo consiste en el diseño, simulación, construcción y caracterización de una estructura magnética vibrante para su potencial uso como base en recolectores de energía (“harvesters”) magnetostrictivos vibracionales. Este elemento transfiere las vibraciones de una fuente del entorno al material magnetostrictivo activo, permitiendo de esta forma la generación de energía a través de los cambios experimentados en la magnetización y los principios de la ley de Faraday. Por lo tanto, su rendimiento es esencial en la siguiente conversión energética en el dispositivo recolector. En la primera parte del trabajo se realizarán varias simulaciones numéricas (con MATLAB® y Gmsh© ) para verificar la viabilidad del diseño y optimizar el sistema. Esta tarea se realizará a través de la modificación de parámetros relevantes para reducir la frecuencia de resonancia y maximizar las tensiones generadas en el material activo para obtener la máxima potencia de salida. La reducción de la frecuencia de resonancia está justificada porque la mayoría de los procesos industriales tienen lugar a frecuencias entorno a o incluso por debajo de los 100 Hz. En este rango de frecuencias los recolectores piezoeléctricos, los más comúnmente utilizados, presentan desventajas significativas relacionadas con el progresivo aumento de sus dimensiones conforme la frecuencia disminuye. En este contexto, un diseño de estructura compacta, sencilla, duradera y barata podría mejorar el rendimiento de la recolección de energía vibracional en aplicaciones industriales gracias a la sustitución de los recolectores piezoeléctricos por recolectores magnetostrictivos. En la segunda parte del proyecto se construirá un prototipo en el laboratorio y se caracterizará para comprobar si los resultados experimentales coinciden con los resultados de las simulaciones numéricas y si se obtiene un resultado satisfactorio en términos de frecuencia de resonancia y amplitud de vibración.Publication Open Access Exploring the potential of the dynamic hysteresis loops via high field, high frequency and temperature adjustable AC magnetometer for magnetic hyperthermia characterization(Taylor & Francis, 2020) Rodrigo, Irati; Castellanos Rubio, Idoia; Garayo Urabayen, Eneko; Arriortua, Oihane K.; Insausti, Maite; Ciencias; ZientziakAim: The Specific Absorption Rate (SAR) is the key parameter to optimize the effectiveness of magnetic nanoparticles in magnetic hyperthermia. AC magnetometry arises as a powerful technique to quantify the SAR by computing the hysteresis loops' area. However, currently available devices produce quite limited magnetic field intensities, below 45mT, which are often insufficient to obtain major hysteresis loops and so a more complete and understandable magneticcharacterization. This limitation leads to a lack of information concerning some basic properties, like the maximum attainable (SAR) as a function of particles' size and excitation frequencies, or the role of the mechanical rotation in liquid samples. Methods: To fill this gap, we have developed a versatile high field AC magnetometer, capable of working at a wide range of magnetic hyperthermia frequencies (100 kHz–1MHz) and up to field intensities of 90mT. Additionally, our device incorporates a variable temperature system for continuous measurements between 220 and 380 K. We have optimized the geometrical properties of the induction coil that maximize the generated magnetic field intensity. Results: To illustrate the potency of our device, we present and model a series of measurements performed in liquid and frozen solutions of magnetic particles with sizes ranging from 16 to 29 nm. Conclusion: We show that AC magnetometry becomes a very reliable technique to determine the effective anisotropy constant of single domains, to study the impact of the mechanical orientation in the SAR and to choose the optimal excitation parameters to maximize heating production under human safety limits.Publication Open Access Fe-C nanoparticles obtained from thermal decomposition employing sugars as reducing agents(Elsevier, 2020) Cervera Gabalda, Laura María; Pérez de Landazábal Berganzo, José Ignacio; Garayo Urabayen, Eneko; Monteserín, María; Larumbe Abuin, Silvia; Martín, F.; Gómez Polo, Cristina; Zientziak; Institute for Advanced Materials and Mathematics - INAMAT2; Ciencias; Gobierno de Navarra / Nafarroako Gobernua; Universidad Pública de Navarra / Nafarroako Unibertsitate PublikoaThe aim of the work is to present a comparative analysis (structural and magnetic) of Fe-C nanocomposites obtained by the thermal decomposition of sugars (fructose, glucose and sucrose) employing FeCl3 as Fe3+ precursor. The thermal decomposition was followed through Thermogravimetry (TGA) and Fourier-transform infrared spectroscopy (FTIR), X-ray diffraction, High Resolution Transmission Electron Microscopy (HRTEM) and Raman spectroscopy. The results indicate the reduction of Fe3+ under the performed thermal treatments and the achievement at high annealing temperatures of Fe-C nanostructures (coexistence of α-Fe and Fe3C nanoparticles surrounded by a carbon matrix). The magnetic characterization performed by dc SQUID magnetometry, shows an antiferromagnetic response in the initial stages of the decomposition process, and a ferromagnetic behavior linked to the Fe-based nanoparticles. The magnetic induction heating was analyzed through the ac hysteresis loops. Moderate Specific Absorption Rate (SAR) is obtained in Fe-C nanoparticles (~ 70 W/gFe), ascribed to the large nanoparticle size. The combination of porous carbon structure and ferromagnetic response of the Fe-C nanoparticles (i.e. local temperature increase under ac magnetic field) enlarge the emerging applications of these carbonaceous nanocomposites.Publication Open Access Iron oxide nanorings and nanotubes for magnetic hyperthermia: the problem of intraparticle interactions(MDPI, 2021) Das, Raja; Alonso Masa, Javier; Kalappattil, Vijaysankar; Nemati, Zohreh; Rodrigo, Irati; Garayo Urabayen, Eneko; García, José Ángel; Manh-Huong, Phan; Srikanth, Hariharan; Ciencias; ZientziakMagnetic interactions can play an important role in the heating efficiency of magnetic nanoparticles. Although most of the time interparticle magnetic interactions are a dominant source, in specific cases such as multigranular nanostructures intraparticle interactions are also relevant and their effect is significant. In this work, we have prepared two different multigranular magnetic nanostructures of iron oxide, nanorings (NRs) and nanotubes (NTs), with a similar thickness but different lengths (55 nm for NRs and 470 nm for NTs). In this way, we find that the NTs present stronger intraparticle interactions than the NRs. Magnetometry and transverse susceptibility measurements show that the NTs possess a higher effective anisotropy and saturation magnetization. Despite this, the AC hysteresis loops obtained for the NRs (0-400 Oe, 300 kHz) are more squared, therefore giving rise to a higher heating efficiency (maximum specific absorption rate, SAR(max) = 110 W/g for the NRs and 80 W/g for the NTs at 400 Oe and 300 kHz). These results indicate that the weaker intraparticle interactions in the case of the NRs are in favor of magnetic hyperthermia in comparison with the NTs.Publication Open Access Magnetic binary encoding system based on 3D printing and GMI detection prototype(Elsevier, 2022) Beato López, Juan Jesús; Algueta-Miguel, Jose M.; Galarreta Rodríguez, Itziar; López Ortega, Alberto; Garayo Urabayen, Eneko; Gómez Polo, Cristina; Aresti Bartolomé, Maite; Soria Picón, Eneko; Pérez de Landazábal Berganzo, José Ignacio; Ciencias; Zientziak; Ingeniería Eléctrica, Electrónica y de Comunicación; Ingeniaritza Elektrikoa, Elektronikoa eta Telekomunikazio Ingeniaritza; Institute for Advanced Materials and Mathematics - INAMAT2; Institute of Smart Cities - ISC; Gobierno de Navarra / Nafarroako Gobernua; Universidad Pública de Navarra / Nafarroako Unibertsitate PublikoaIn this work, the feasibility of a magnetic binary encoding system using 3D printing technology is analyzed. The study has a double interest, that is, the possibility of printing a 3D piece that contains the codified information and the development of a system for its decoding. For this purpose, magnetic nanoparticles (magnetite Fe3O4) were embedded in a polymeric matrix of Polylactic Acid (PLA) and Poly-ε-caprolactone (PCL). Similar to a conventional barcode, a rectangular piece with an alternating pattern of strips with absence (only polymer) and a 5 wt% of embedded magnetic nanoparticles was 3D printed employing the Fused Deposition Modelling tech- nique (FDM). The information was decoded by means of a Giant Magnetoimpedance (GMI) sensor-based pro- totype, by scanning the surface of the piece and measuring the changes in the magnetic field. As sensor nucleus, an amorphous soft magnetic wire of nominal composition (Co0.94 Fe0.06)72.5 Si12.5 B15 was employed. The decoding prototype incorporates a homemade electronic sensor interface that permits, at the time, the GMI sensor excitation and the subsequent signal conditioning to optimize its response. The output signal enables the detection of the magnetite nanoparticles and the magnetic decoding of the encoded information (“1” and “0”, presence or absence of the magnetic nanoparticles, respectively).Publication Open Access Magnetically activated 3D printable polylactic acid/polycaprolactone/magnetite composites for magnetic induction heating generation(Springer, 2023) Galarreta Rodríguez, Itziar; López Ortega, Alberto; Garayo Urabayen, Eneko; Beato López, Juan Jesús; La Roca, Paulo Matías; Sánchez-Alarcos Gómez, Vicente; Recarte Callado, Vicente; Gómez Polo, Cristina; Pérez de Landazábal Berganzo, José Ignacio; Ciencias; Zientziak; Institute for Advanced Materials and Mathematics - INAMAT2; Universidad Pública de Navarra / Nafarroako Unibertsitate PublikoaAdditive manufacturing technology has attracted the attention of industrial and technological sectors due to the versatility of the design and the easy manufacture of structural and functional elements based on composite materials. The embedding of magnetic nanoparticles in the polymeric matrix enables the development of an easy manufacturing process of low-cost magnetically active novel polymeric composites. In this work, we report a series of magnetic composites prepared by solution casting method combining 5 to 60 wt.% of 140 ± 50 nm commercial Fe3O4 nanoparticles, with a semi-crystalline, biocompatible, and biodegradable polymeric blend made of polylactic acid (PLA) and polycaprolactone (PCL). The composites were extruded, obtaining 1.5 ± 0.2 mm diameter continuous and flexible filaments for fused deposition modelling 3D printing. The chemical, magnetic, and calorimetric properties of the obtained filaments were investigated by differential scanning calorimetry, thermogravimetric analysis, magnetometry, and scanning electron microscopy. Furthermore, taking advantage of the magnetic character of the filaments, their capability to generate heat under the application of low-frequency alternating magnetic fields (magnetic induction heating) was analyzed. The obtained results expose the versatility of these easy manufacturing and low-cost filaments, where selecting a desired composition, the heating capacity can be properly adjusted for those applications where magnetic induction plays a key role (i.e., magnetic hyperthermia, drug release, heterogeneous catalysis, water electrolysis, gas capture, or materials synthesis).Publication Open Access Martensitic transformation controlled by electromagnetic field: from experimental evidence to wireless actuator applications(Elsevier, 2022) Garayo Urabayen, Eneko; La Roca, Paulo Matías; Gómez Polo, Cristina; Sánchez-Alarcos Gómez, Vicente; Recarte Callado, Vicente; Pérez de Landazábal Berganzo, José Ignacio; Zientziak; Institute for Advanced Materials and Mathematics - INAMAT2; Ciencias; Gobierno de Navarra / Nafarroako GobernuaMechanical actuators based on shape memory alloys (SMA) are becoming a key component in the development of novel soft robotic applications and surgically implantable devices. Their working principle relies in the temperature induced martensitic transformation (MT), which is responsible of the actuation mechanism. In this work, we found experimental evidence to show that the martensitic transformation can be controlled by electromagnetic field (EF) by a wireless process in ferromagnetic shape memory alloys. It is shown that the martensitic transformation can be driven by an external EF (frequency 45 kHz) while the specific absorption rate (SAR), which was determined through real-time dynamic magnetization measurements, allows the instantaneous monitoring of the transformation evolution. On the basis of the obtained results, we propose a strategy to achieve a battery-free wireless SMA actuator that can be remotely controlled. This concept can be applicable to other SMA material that exhibit a similar magneto-structural phase transitionPublication Open Access Monitoring structural transformations in metamagnetic shape memory alloys by non-contact GMI technology(IOP Publishing, 2023) Beato López, Juan Jesús; La Roca, Paulo Matías; Algueta-Miguel, Jose M.; Garayo Urabayen, Eneko; Sánchez-Alarcos Gómez, Vicente; Recarte Callado, Vicente; Gómez Polo, Cristina; Pérez de Landazábal Berganzo, José Ignacio; Ciencias; Ingeniería Eléctrica, Electrónica y de Comunicación; Institute for Advanced Materials and Mathematics - INAMAT2; Institute of Smart Cities - ISC; Zientziak; Ingeniaritza Elektrikoa, Elektronikoaren eta Telekomunikazio IngeniaritzarenDifferent applications based on metamagnetic shape memory alloy (MSMA) require monitoring the evolution of the martensitic transformation (MT) to optimize the actuation mechanism. To avoid interaction with the active material, a non-contact technique would be ideal. Nevertheless, non-contact detection involves complex methods like diffraction, optical analysis, or electromagnetic technology. The present work demonstrates that the MT can be monitored without interaction with the active material using a low-cost technology based on the Giant Magnetoimpedance (GMI) effect. The GMI sensor is based on a (CoFe)SiB soft magnetic wire submitted to an alternating current and whose second harmonic voltage variation allows to detect changes in the strength of the stray magnetic fields linked to the metamagnetic phase transition. The sensor has been tested using the MT of a NiMnInCo MSMA. A specific application for environmental temperature control using the non-contact GMI sensor is proposed.Publication Open Access Nanoflowers versus magnetosomes: comparison between two promising candidates for magnetic hyperthermia therapy(Institute of Electrical and Electronics Engineers Inc., 2021) Jefremovas, Elizabeth M.; Gandarias, Lucía; Rodrigo, Irati; Marcano, Lourdes; Gruttner, Cordula; García, José Ángel; Garayo Urabayen, Eneko; Orue, Iñaki; García-Prieto, Ana; Muela, Alicia; Fernández-Gubieda, María Luisa; Alonso, Javier; Fernández Barquín, Luis; Ciencias; ZientziakMagnetic Fluid Hyperthermia mediated by iron oxide nanoparticles is one of the mostpromising therapies for cancer treatment. Among the different candidates, magnetite and maghemite nanoparticles have revealed to be some of the most promising candidates due to both their performance andtheir biocompatibility. Nonetheless, up to date, the literature comparing the heating efficiency of magnetiteand maghemite nanoparticles of similar size is scarce. To fill this gap, here we provide a comparison between commercial Synomag Nanoflowers (pure maghemite) and bacterial magnetosomes (pure magnetite)synthesized by the magnetotactic bacterium Magnetospirillum gryphiswaldenseof〈D〉 ≈40–45 nm. Bothtypes of nanoparticles exhibit a high degree of crystallinity and an excellent degree of chemical purity andstability. The structural and magnetic properties in both nanoparticle ensembles have been studied by meansof X–Ray Diffraction, Transmission Electron Microscopy, X–Ray Absorption Spectroscopy, and SQUIDmagnetometry. The heating efficiency has been analyzed in both systems using AC magnetometry at severalfield amplitudes (0–88 mT) and frequencies (130, 300, and 530 kHz).Publication Open Access Non-linear GMI decoding in 3D printed magnetic encoded systems(Elsevier, 2023) Beato López, Juan Jesús; Algueta-Miguel, Jose M.; Galarreta Rodríguez, Itziar; Garayo Urabayen, Eneko; López Ortega, Alberto; Gómez Polo, Cristina; Pérez de Landazábal Berganzo, José Ignacio; Ciencias; Ingeniería Eléctrica, Electrónica y de Comunicación; Institute for Advanced Materials and Mathematics - INAMAT2; Institute of Smart Cities - ISC; Zientziak; Ingeniaritza Elektrikoa, Elektronikoaren eta Telekomunikazio Ingeniaritzaren; Universidad Pública de Navarra / Nafarroako Unibertsitate PublikoaThe nonlinear giant magnetoimpedance (GMI) effect was explored as a highly sensitive sensing technology in 3D-printed magnetic encoded systems. Magnetic nanoparticles with low (magnetite, Fe3O4) and high (Co ferrite, Co0.7Fe2.3O4) magnetic remanence were embedded (10 wt%) in a polymeric matrix of Polylactic Acid (PLA) and Poly-ε-caprolactone (PCL) and extruded in magnetic filaments to be 3D printed by the Fused Deposition Modelling technique (FDM). Two different geometries were constructed namely, individual magnetic strips and fixed barcoded pieces. The stray magnetic fields generated by the magnetic nanoparticles were detected through the non-linear (second harmonic) GMI voltage using a soft magnetic CoFeSiB wire as the nucleus sensor. The decoding response was analyzed as a function of the magnetization remanence of the nanoparticles, the distance between the individual magnetic strips, and the position (height) of the GMI decoding sensor. It has been shown that modification of the net magnetization direction of each individual fixed strip within the barcode geometry is possible through the application of local external magnetic fields. This possibility improves the versatility of the 3D binary encoding system by adding an additional state (0 without nanoparticles, 1 or −1 depending on the relative orientation of the net magnetization along the strips) during the codifying procedure.Publication Open Access Preparation of selenium-based drug-modified polymeric ligand-functionalised Fe3O4 nanoparticles as multimodal drug carrier and magnetic hyperthermia inductor(MDPI, 2023) Galarreta Rodríguez, Itziar; Etxebeste-Mitxeltorena, Mikel; Moreno, Esther; Plano, Daniel; Sanmartín, Carmen; Megahed, Saad; Feliu, Neus; Parak, Wolfgang J.; Garayo Urabayen, Eneko; Gil de Muro, Izaskun; Lezama, Luis; Ruiz de Larramendi, Idoia; Insausti, Maite; Ciencias; Zientziak; Institute for Advanced Materials and Mathematics - INAMAT2In recent years, much effort has been invested into developing multifunctional drug delivery systems to overcome the drawbacks of conventional carriers. Magnetic nanoparticles are not generally used as carriers but can be functionalised with several different biomolecules and their size can be tailored to present a hyperthermia response, allowing for the design of multifunctional systems which can be active in therapies. In this work, we have designed a drug carrier nanosystem based on Fe3O4 nanoparticles with large heating power and 4-amino-2-pentylselenoquinazoline as an attached drug that exhibits oxidative properties and high selectivity against a variety of cancer malignant cells. For this propose, two samples composed of homogeneous Fe3O4 nanoparticles (NPs) with different sizes, shapes, and magnetic properties have been synthesised and characterised. The surface modification of the prepared Fe3O4 nanoparticles has been developed using copolymers composed of poly(ethylene-alt-maleic anhydride), dodecylamine, polyethylene glycol and the drug 4-amino-2-pentylselenoquinazoline. The obtained nanosystems were properly characterised. Their in vitro efficacy in colon cancer cells and as magnetic hyperthermia inductors was analysed, thereby leaving the door open for their potential application as multimodal agents.Publication Open Access Steering the synthesis of Fe3O4 nanoparticles under sonication by using a fractional factorial design(Elsevier, 2021) Echeverría Morrás, Jesús; Moriones Jiménez, Paula; Garrido Segovia, Julián José; Ugarte Martínez, María Dolores; Cervera Gabalda, Laura María; Garayo Urabayen, Eneko; Gómez Polo, Cristina; Pérez de Landazábal Berganzo, José Ignacio; Ciencias; Zientziak; Estadística, Informática y Matemáticas; Estatistika, Informatika eta Matematika; Institute for Advanced Materials and Mathematics - INAMAT2; Universidad Pública de Navarra / Nafarroako Unibertsitate Publikoa; Gobierno de Navarra / Nafarroako GobernuaSuperparamagnetic iron oxide nanoparticles (MNPs) have the potential to act as heat sources in magnetic hyperthermia. The key parameter for this application is the specific absorption rate (SAR), which must be as large as possible in order to optimize the hyperthermia treatment. We applied a Plackett-Burman fractional factorial design to investigate the effect of total iron concentration, ammonia concentration, reaction temperature, sonication time and percentage of ethanol in the aqueous media on the properties of iron oxide MNPs. Characterization techniques included total iron content, Fourier Transform Infrared Spectroscopy, X-Ray Diffraction, High Resolution Transmission Electron Microscopy, and Dynamic Magnetization. The reaction pathway in the coprecipitation reaction depended on the initial Fe concentration. Samples synthesized from 0.220 mol L−1 Fe yielded magnetite and metastable precipitates of iron oxyhydroxides. An initial solution made up of 0.110 mol L−1 total Fe and either 0.90 or 1.20 mol L−1 NH3(aq) led to the formation of magnetite nanoparticles. Sonication of the reaction media promoted a phase transformation of metastable oxyhydroxides to crystalline magnetite, the development of crystallinity, and the increase of specific absorption rate under dynamic magnetization.Publication Open Access Unlocking the potential of magnetotactic bacteria as magnetic hyperthermia agents(Wiley, 2019) Gandía, David; Gandarias, Lucía; Rodrigo, Irati; Robles García, Joshua; Das, Raja; Garayo Urabayen, Eneko; García, José Ángel; Ciencias; ZientziakMagnetotactic bacteria are aquatic microorganisms that internally biomineralize chains of magnetic nanoparticles (called magnetosomes) and use them as a compass. Here it is shown that magnetotactic bacteria of the strain Magnetospirillum gryphiswaldense present high potential as magnetic hyperthermia agents for cancer treatment. Their heating efficiency or specific absorption rate is determined using both calorimetric and AC magnetometry methods at different magnetic field amplitudes and frequencies. In addition, the effect of the alignment of the bacteria in the direction of the field during the hyperthermia experiments is also investigated. The experimental results demonstrate that the biological structure of the magnetosome chain of magnetotactic bacteria is perfect to enhance the hyperthermia efficiency. Furthermore, fluorescence and electron microscopy images show that these bacteria can be internalized by human lung carcinoma cells A549, and cytotoxicity studies reveal that they do not affect the viability or growth of the cancer cells. A preliminary in vitro hyperthermia study, working on clinical conditions, reveals that cancer cell proliferation is strongly affected by the hyperthermia treatment, making these bacteria promising candidates for biomedical applications.