Design And Manufacture Of Rotating Magnetic Field Generator Applied To Magnetic Transfection

Although contemporary medicine is rather advanced,people are still helpless when dealing with diseases related to gene defects.Currently,the most effective method proposed by scientists to cure gene defects diseases is gene transfection.The method of using external magnetic field for controlling magnetic particle to achieve gene transfection is called magnetic transfection,which provides a new potential solution for gene therapy.However,there are many challenges in achieving magnetic transfection.One of challenges is how to develop a safe and controllable external magnetic field generating device that can improve gene transfection efficiency.So far,there are only a few existing rotary magnetic field generating devices suitable for magnetic transfection.In addition,the uniformity of magnetic field generated is not high enough and the average efficiency of current magnetic field is low.Aiming to solve these problems above,this invention utilizes solenoid coil's advantages of simple design,high strength and high uniformity and the advantage that there is no coupling complexity between two poles of electromagnet like magnetic circuits.A new method of combining solenoid coil and a two-pole electromagnet is proposed in this paper.In this way,a novel rotating magnetic field generator with a simple structure design,high strength and high uniformity is designed.The main research content is as follows:This paper expounds the generation principle of rotary magnetic field,based on which orthogonal combination of solenoid coil and two-pole electromagnet is proposed.This method uses COMSOL to simulate the magnetic field generated by solenoid and two poles electromagnet.The uniformity of the magnetic field generated by the solenoid and the two poles electromagnet and the average efficiency of the current magnetic field are analyzed.Then,the motion model of magnetic particles in a uniform field is established and the stress condition is analyzed.The simulation analysis is performed on the motion characteristics of the magnetic particles in a rotary magnetic field.This study lays the foundation for later research on magnetic particle's motion behavior and the mechanism of magnetic particles' effects on magnetic transfection efficiency.In this paper,the model of rotating magnetic field generating device's main circuit is established,and the filtering performance of inverter main circuit's three output filters is analyzed and compared.Through analysis and comparison,the LCL filter is selected as the filter circuit.As for the LCL filter's amplitude peak problem at the resonant frequency,which can easily trigger system resonance,a passive damping control method is adopted,and the main circuit of the power inverter is simulated to verify system's stability.Based on the simulation design and analysis above,the rotating magnetic field generating device was designed and produced.The closed-loop feedback control of the magnetic field amplitude and load current phase difference was realized by using search coil's induced voltage and phase detection technology.The design process of the system hardware circuit as well as the development process of the software part is elaborated in detail.Human-computer interactive interface is also realized.Due to the limits of experimental condition,only experimental tests on the device itself are conducted.Experiments have shown that the device can generate magnetic field strength and rotating magnetic field with adjustable frequency which reaches the design target and satisfies the requirements for preliminary experiment of magnetic transfection.This paper lays a good experimental foundation for subsequent magnetic transfection-related experiments.