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arXiv · 2207.14551

Estimating the heating of complex nanoparticle aggregates for magnetic hyperthermia

Javier Ortega Julia·Daniel Ortega·Jonathan Leliaert
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Abstract

Understanding and predicting the heat released by magnetic nanoparticles is central to magnetic hyperthermia treatment planning. These nanoparticles tend to form aggregates when injected in living tissues, which alters their response to the applied alternating magnetic field and prevents predicting the released heat accurately. We performed an in silico analysis to investigate the heat released by nanoparticle aggregates featuring different size and fractal geometry factors. By digitally mirroring aggregates seen in biological tissues, we found that the average heat released per particle stabilizes starting from moderately small aggregates, facilitating the estimates for their larger counterparts. Additionally, we studied the heating performance of particle aggregates over a wide range of fractal parameters. We compared this result with the heat released by non-interacting nanoparticles to quantify the reduction of heating power after being instilled into tissues. This set of results can be used to estimate the expected heating in vivo based on the experimentally determined nanoparticle properties.

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Javier Ortega Julia, Daniel Ortega, Jonathan Leliaert. 2022-07-29. Estimating the heating of complex nanoparticle aggregates for magnetic hyperthermia. https://doi.org/10.1039/d3nr01269g

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