Design, Implementation, and Analysis of a 3-D Magnetic Tweezer System With High Magnetic Field Gradient

This paper presents the design, modeling, and implementation of an innovative, high-power hexapole magnetic tweezer system for 3-D micromanipulations. The designed system has six sharp-tipped magnetic poles that are aligned in an inclined Cartesian coordinate system. The installation platform including yokes was made by a 3-D printer using the magnetized material. The magnetic field was generated through the tips after current was applied to individual electromagnetic coils located on each magnetic pole. The effective working space in the system is larger than other similar designs, so it is available to give a wide range of mobility for a microrobot. Strong magnetic fields of up to 6 mT can be generated in the center of the working space, which provides better performance on microscale robot operations. The numerical magnetic field profile was simulated using COMSOL Multiphysics, and the results were compared with the experimental measurement of a magnetic field in the designed system. We prove that the developed hexapole magnetic tweezer has enough power and controllability to guide microswimmers in Newtonian fluid environments and can follow 3-D trajectories. The system will be optimized further to be implemented into cell penetration research. Finally, the application will be deployed into in vivo based environments.