A versatile induction heating system for magnetic hyperthermia studies under different experimental conditions

In recent decades, magnetic hyperthermia using magnetic nanoparticles, a promising but quite challenging method, has proven to be an effective cancer therapy procedure. In hyperthermia, heat, which is generated by magnetic nanoparticles exposed to a radiofrequency magnetic field, is employed to battle cancerous cells. Ideally, devices for magnetic hyperthermia should provide a variety of field amplitudes and frequencies for generating an appropriate and powerful alternating magnetic field. Here, we report the design and evaluation of a versatile system which provides different experimental setup possibilities for magnetic hyperthermia. The proposed system is a derivative of the Mazzilli inverter, which directly follows the resonant frequency of the LC tank circuit independent of its component. The feasibility of the system for hyperthermia studies was examined using iron oxide nanoparticles prepared by the coprecipitation method. Different experimental conditions including nanoparticles in solution and dispersed in gelatin phantoms were evaluated. Four different coils including two solenoids, a pancake, and a Helmholtz-like format were successfully tested. Using these coils, 18 different operation frequencies in the frequency band of 63-530 kHz with field strengths up to 27.2 kA/m were achieved.