Hadadian Yaser, Azimbagirad Mehran, Navas Elcio A, Pavan Theo Z
Department of Physics, FFCLRP, University of São Paulo, Ribeirao Preto, SP CEP 14040-901, Brazil.
Rev Sci Instrum. 2019 Jul;90(7):074701. doi: 10.1063/1.5080348.
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.
近几十年来，使用磁性纳米颗粒的磁热疗法已被证明是一种有效的癌症治疗方法，该方法前景广阔但颇具挑战性。在热疗中，磁性纳米颗粒暴露于射频磁场时产生的热量被用于对抗癌细胞。理想情况下，磁热疗设备应能提供多种场强和频率，以产生合适且强大的交变磁场。在此，我们报告一种通用系统的设计与评估，该系统为磁热疗提供了不同的实验设置可能性。所提出的系统是马齐利逆变器的衍生版本，它直接跟踪LC振荡电路的谐振频率，而与电路元件无关。使用通过共沉淀法制备的氧化铁纳米颗粒，检验了该系统用于热疗研究的可行性。评估了不同的实验条件，包括纳米颗粒在溶液中以及分散在明胶模型中的情况。成功测试了四种不同的线圈，包括两个螺线管、一个扁平线圈和一种类似亥姆霍兹线圈的形式。使用这些线圈，在63 - 530kHz频段内实现了18种不同的工作频率，场强高达27.2kA/m。
