Development of a focusing pulsed magnetic field system for in Vivo experiments

The design of a spherical coil system for pulsed magnetic field (PMF) exposure is presented for in vivo experiments with tumor-bearing animals. The system has greater focusing capability than conventional systems and has advantages in terms of effectiveness and safety. In the simulation part of the study, the magnetic field distribution of two spherical coil systems were studied using a finite element code, where the influences of coil radius and wire diameter were analyzed to optimize the final design. The simulation results indicate that the coil radius has significant effects on the magnetic field distribution, while the effect of wire diameter is negligible. Based on the designed parameters, a coil system was then developed and the magnetic field focusing ability of the system was measured and evaluated. The coil system has a better focusing performance with the central magnetic induction Bm of 1.3×10^-4 T and S80% of 2.8×10^-3 m². The spherical coil system contributes to the system´s focusing ability, which is expected to help in experiments for tumor treatment in the near future.