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arXiv · 2111.00081

Raiders of the lost SAR: Radiofrequency cycles of magnetic nanoflowers inside a tumor

I. J. Bruvera·D. G. Actis·P. Soto·V. Blank·L. Roguin·M. B. Fernandez van Raap·P. Mendoza Zelis
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Abstract

Radiofrequency magnetic cycles of \textit{ex vivo} melanoma tumor tissue loaded with Fe$_3$O$_4$ nanoflowers (NF) were measured for several field conditions and compared with the cycles of a ferrogel (FG) obtained incorporating identical NF in agarose gel. Results were studied in order to understand a reported specific power dissipation (SAR) reduction of the NF in the actual application medium (tumor) in comparison with a typical characterization model as the FG. The linearity of the response, together with coercive field and SAR values were analyzed.\\ Additionally, a novel method for the determination of the NF mean relaxation time is presented. Results show a systematic difference in magnetic response between the NF incorporated in the tumor and those in the FG for all field settings (\{98, 170, 260\} kHz and \{17.4, 54.0\} kA/m) with SAR reductions above 50\%.

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I. J. Bruvera, D. G. Actis, P. Soto, V. Blank, L. Roguin, M. B. Fernandez van Raap, P. Mendoza Zelis. 2021-10-29. Raiders of the lost SAR: Radiofrequency cycles of magnetic nanoflowers inside a tumor. https://doi.org/10.1016/j.jmmm.2022.169869

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