电工技术学报2024，Vol.39Issue(13)：3907-3916,10.DOI:10.19595/j.cnki.1000-6753.tces.230649
用于细胞活性研究的高重频脉冲磁场装置
High Repetitive Frequency Pulsed Magnetic Field Generator for Cell Activity Studies
摘要
Abstract
Cell responses to magnetic fields obey an electromagnetic efficacy window defined by a specific combination of frequency,amplitude and time of exposure.Previous studies suggest that the specific pulsed magnetic field sequences have the potential to modulate the regulation of certain types of cells and tissues.Based on the needs of cell research,it is necessary to develop a programmable pulsed magnetic field generator with a peak magnetic field intensity up to 10 mT,a high stability,a wide range of frequency,a steep pulse edge and a configurable Inter-Stimulus Interval.However,the magnet is a large inductive load,the magnet voltage in the rising edge of the pulse needs to be tens of times higher than that in the flat top stage,which makes it challenge to adjust the magnet current with both high repetitive frequency and high precision. In this paper,a high repetitive frequency pulsed magnetic field generator to solve the above contradiction was developed.Firstly,the structure of the magnet was designed as a double-layer helical coil,and the unevenness of the cell culture area at the center was 2.4％.The ratio of magnetic field to the current in the magnet was 2 mT/A,and the requirements of the power supply were presented based on the magnet parameters.Secondly,a two-stage joint topology consisting of a synchronous Buck circuit and a bridge circuit was proposed.The working principle of the topology was explained and the calculation formulas for the parameters of the main components were derived.Lastly,in order to achieve the smooth transition of the current from the rapid rise to the stable value,the small-signal analysis of the power supply system was performed to obtain the transfer function of the duty cycle and the output current.Using the results,this paper configured a hybrid controller utilizing the time-optimal dynamic response of the hysteresis controller and the strong steady-state tracking capability of the PI controller.The feasibility of the scheme was verified by simulations. Based on these,a portable high repetitive frequency pulsed magnetic field generator with a frequency range of 1 Hz～5 kHz,pulse edge less than 50μs,adjustable precision of 0.1 mT,and peak intensity up to 10 mT was fabricated.A user-friendly Human-Machine Interface was developed to facilitate the effortless recording of experimental data and monitoring of device status.The ratio of magnetic field to the current was measured in the experiments,and the error was less than 0.15％compared to the theoretical values.This paper tested the magnetic field waveforms for different target values,demonstrating the flexibility and the stability of the device.To mitigate the impact of parasitic capacitance on the magnet at high frequencies,the parasitic capacitance value was calculated followed by the design of a continuous current circuit to suppress the oscillation of the magnet voltage.Finally,biological experiments were carried out to observe the effect of the magnetic field on the fertilization ability and embryo development ability of oocytes from aged mice.Exposed to the 1 mT pulsed magnetic field sequence for 10 minutes,the blastocyst developmental rate increased from 15.15％to 52.94％.These results indicate that the pulsed magnetic field significantly enhances the developmental ability of oocytes in elderly mice.关键词
重频脉冲磁场/细胞活性/磁场发生装置/混合型控制器Key words
Repetitive pulsed magnetic field/cell activity/magnetic field generator/hybrid controller分类
信息技术与安全科学引用本文复制引用
樊俊显,张绍哲,李可欣,相文佩,韩小涛..用于细胞活性研究的高重频脉冲磁场装置[J].电工技术学报,2024,39(13):3907-3916,10.基金项目
国家自然科学基金青年基金(52107152)和国家自然科学基金-创新群体项目(51821005)资助. （52107152）
