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arXiv · 1403.6432

Magnetic nanoparticle sensing: decoupling the magnetization from the excitation field

Daniel B Reeves·John B Weaver
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Abstract

Remote sensing of magnetic nanoparticles has exciting applications for magnetic nanoparticle hyperthermia and molecular detection. We introduce, simulate, and experimentally demonstrate an innovation---a sensing coil that is geometrically decoupled from the excitation field---for magnetic nanoparticle spectroscopy that increases the flexibility and capabilities of remote detection. The decoupling enhances the sensitivity absolutely; to small amounts of nanoparticles, and relatively; to small changes in the nanoparticle dynamics. We adapt a previous spectroscopic method that measures the relaxation time of nanoparticles and demonstrate a new measurement of nanoparticle temperature that could potentially be used concurrently during hyperthermia.

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Daniel B Reeves, John B Weaver. 2014-03-25. Magnetic nanoparticle sensing: decoupling the magnetization from the excitation field. https://doi.org/10.1088/0022-3727/47/4/045002

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