Heating Properties of RF Capacitive Applicator with Magnetic Nanoparticles

Abstract

: This study describes the temperature properties of the radio frequency ( RF ) capacitive applicator with magnetic nanoparticles. In a clinic, two types of heating devices are most commonly used. One among these heating devices is a dielectric heating applicator, whereas the other type is an induction heating applicator. One of the disadvantages of dielectric heating applicators is their tendency to overheat the fat layers. Further, a cooling system is attached to reduce overheating. However, overheating remains one of most significant disadvantages of a dielectric applicator. In contrast, it is difficult to produce localized heating energy to the deep-seated tumors using induction heating applicators. To overcome these problems, we propose a method for using magnetic nanoparticles combined with an RF capacitive applicator. Further, the effectiveness of the proposed method has been examined by performing computer simulations and heating experiments using our prototype RF capacitive applicator. This study describes the temperature properties that are associated with the usage of magnetic nanoparticles and a hyperthermia applicator. First, the characteristics of a dielectric heating device and an induction heating device are described. Second, the electric properties of magnetic nanoparticles that exhibit concentrations ranging from 20 to 60 mg / cm 3 are measured in the frequency range from 100 MHz to 1.0 GHz, further, the temperature properties of the RF capacitive applicator with magnetic nanoparticles are calculated using the finite element method (FEM). Finally, the heating experiments are conducted using our prototype RF capacitive applicator and infrared thermal camera. These results of this study indicated that dielectric heating was the dominant heating mechanism in case of an RF capacitive applicator with magnetic nanoparticles. Additionally, it was suggested that the usage of magnetic nanoparticles will make it possible to control the heated area inside a patient ʼ s body. Thus, we observed that it was possible to use magnetic nanoparticles for performing effective hyperthermia treatment based on the results of both computer simulations and heating experiments.