Exploring the potential of the dynamic hysteresis loops via high field, high frequency and temperature adjustable AC magnetometer for magnetic hyperthermia characterization
Fecha
2020Autor
Versión
Acceso abierto / Sarbide irekia
Tipo
Artículo / Artikulua
Versión
Versión publicada / Argitaratu den bertsioa
Impacto
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10.1080/02656736.2020.1802071
Resumen
Aim: 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 hyst ...
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Aim: 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. [--]
Materias
AC magnetometry,
Specific absorption rate,
SAR,
Magnetic hyperthermia,
Stoner–Wohlfarth model based theories
Editor
Taylor & Francis
Publicado en
International Journal of Hyperthermia, 2020, 37(1), 976-991
Departamento
Universidad Pública de Navarra. Departamento de Ciencias /
Nafarroako Unibertsitate Publikoa. Zientziak Saila
Versión del editor
Entidades Financiadoras
I.R. acknowledges the Basque Government for her fellowship (PRE 2017 2 0089) and for the financial supporting of this work (IT-1005-16). Dr I. Castellanos-Rubio thanks the The Horizon 2020 Programme for the financial support provided through a Marie Sklodowska-Curie fellowship (798830).