Symmetric/asymmetric positioning of a permanent magnet pair for selective magnetic hyperthermia
Magnetic fluid hyperthermia (MFH) is a new generation cancer treatment method in which magnetic energy is converted into heat energy. One of the challenges that arise in MFH applications is the limited control of magnetic nanoparticle (MNP) oscillations. New approaches such as the localization of MNP oscillations are being investigated to overcome this problem. In this study, it is studied to manipulate magnetic field-free zone (FFR) form and location by symmetric and asymmetric displacements of static magnetic field sources. Firstly, finite element method simulation was used to study gradient patterns. Later, with the experiment setup gradient patterns were created with parametric changes depending on distance and angle, then patterns were mapped. According to the mapping results; it is seen that FFR can shrink at the center and change its form from the surface to the line. Additionally, it is determined that focus of FFR can be moved off-center, its form can be manipulated, and it can be directed to different parts of the target object. The mapping of the gradient pattern produced by permanent magnets in symmetric and asymmetric situations with linear and angular positioning for selective MFH use is investigated for the first time in this study.