Echeverría Morrás, JesúsMoriones Jiménez, PaulaGarrido Segovia, Julián JoséUgarte Martínez, María DoloresCervera Gabalda, Laura MaríaGarayo Urabayen, EnekoGómez Polo, CristinaPérez de Landazábal Berganzo, José Ignacio2022-02-012023-09-1520210254-058410.1016/j.matchemphys.2021.124760https://academica-e.unavarra.es/handle/2454/42089Superparamagnetic 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.25 p.application/pdfeng© 2021 Elsevier B.V. This manuscript version is made available under the CC-BY-NC-ND 4.0Fractional factorial designMagnetite nanoparticlesPhase transformationSonicationSpecific absorption rateinfo:eu-repo/semantics/articleinfo:eu-repo/semantics/openAccessAcceso abierto / Sarbide irekia