Investigation of the temperature field in the magnetic hyperthermia using FeCrNbB magnetic particles

The control of the temperature field within malignant tissues is an important task in the magnetic hyperthermia. The temperature analysis is a good method to focus the main parameters which can improve the heating mechanisms of the magnetic particles injected within tissues when the magnetic fields are applied. This paper analyses the temperature effects induced within tumoral tissues by the superparamagnetic systems as FeCrNbB, magnetite and maghemite when an external time-dependent magnetic field is applied. A 3D temperature model which predicts the temperature field in a tumoral tissue was developed. The heat generation by Neel and Brown relaxations was modeled using the thermal and magnetic properties of the FeCrNbB particles experimentally determined. Interconnection between particle parameters (composition, size, magnetic and thermal properties), optimum dosage (volume concentration) and the magnetic field parameters (frequency and magnetic field intensity) was studied. The FeCrNbB magnetic systems have a particular behavior with the frequency and amplitude of the AC magnetic field. The temperature gradients induced within the tumor as a result of the heating in the magnetic field are smaller than the ones induced by the magnetite systems. This temperature behaviour can be an advantage in the controlled heating of the tumors.