Magnetic bacteria are a type of bacteria that have the ability to swim in water and possess a unique intracellular organelle called a magnetosome within their cells. Magnetic bacteria move forward using their swimming ability, and when a magnetic field is present in their surroundings, magnetic torque acts on their magnetosomes, causing them to swim along magnetic lines. In this study, we investigated methods for controlling the swimming direction of magnetic bacteria by applying an appropriate external magnetic field, using numerical simulations based on the boundary element method. Specifically, we applied a rotating magnetic field and analyzed the effects of the intensity and rotation period of the rotating magnetic field on the swimming behavior of magnetic bacteria. The results revealed that as the intensity of the rotating magnetic field increases and the period decreases, the rotational diameter of the swimming trajectory becomes smaller. Under the assumptions of this study, it was found that the rotational radius could be reduced to 4.57 μm. On the other hand, it was also found that if the period of the rotating magnetic field is made too short, the circular trajectory becomes distorted.
HASUMI et al. (Wed,) studied this question.