Harmonic dependence of thermal magnetic particle imaging

Thinh Q Bui; Mark-Alexander Henn; Weston L Tew; Megan A Catterton; Solomon I Woods

doi:10.1038/s41598-023-42620-1

Harmonic dependence of thermal magnetic particle imaging

Sci Rep. 2023 Sep 22;13(1):15762. doi: 10.1038/s41598-023-42620-1.

Authors

Thinh Q Bui¹, Mark-Alexander Henn^{2

3}, Weston L Tew², Megan A Catterton^{2

4}, Solomon I Woods²

Affiliations

¹ National Institute of Standards and Technology, Gaithersburg, MD, 20895, USA. [email protected].
² National Institute of Standards and Technology, Gaithersburg, MD, 20895, USA.
³ Department of Chemistry and Biochemistry, University of Maryland, College Park, MD, 20742, USA.
⁴ Department of Mechanical Engineering, Johns Hopkins University, Baltimore, MD, 21287, USA.

Abstract

Advances in instrumentation and tracer materials are still required to enable sensitive, accurate, and localized in situ 3D temperature monitoring by magnetic particle imaging (MPI). We have developed a high-resolution magnetic particle imaging instrument and implemented a low-noise multi-harmonic lock-in detection method to observe and quantify temperature variations in iron oxide nanoparticle tracers using the harmonic ratio method for determining temperature. Using isolated harmonics for MPI and temperature imaging revealed an apparent dependence of imaging resolution on harmonic number. Thus, we present experimental and simulation studies to quantify the imaging resolution dependence on temperature and harmonic number, and directly validate the fundamental origin of MPI imaging resolution on harmonic number based on the concept of a harmonic point-spread-function.

Abstract

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