Quantifying localized heating of synthetic antiferromagnet disk particles with an MPI-MFH platform

Abstract

Recently, a theranostic imaging platform which allows for switching between imaging and therapeutic modes has been realized by integrating a hyperthermia insert into a commercial magnetic particle imaging (MPI) scanner. The platform enables precisely localized heating to a specific target temperature deep in the tissue via magnetic fluid hyperthermia (MFH) as well as visualization of the distribution and quantification of the temperature of magnetic nanoparticle suspensions (MNPs). MPI-assisted MFH helps to overcome the typical constraint of MFH of delivering heat only to e.g., malignant regions without affecting the surrounding healthy tissues and it provides accurate control of the therapy. However, as a cancer therapy, MFH is still limited by the thermal outcome in the targeted region. The heating effectiveness of MFH strongly depends on the magnetization properties of the utilized MNPs. Synthetic antiferromagnet disk particles, feature the design of two ferromagnetic layers separated by a non-magnetic layer, can overcome this limitation by enhancing the hysteretic loss.  In this work, the localized MFH properties of the synthetic antiferromagnet disk particles are explored using the theranostic imaging platform. The heat map is measured, and the thermal resolution is evaluated and compared to simulation results.