A DNA-inspired magnetic millimeter-scale swimmer with double conical chains

Microswimmers have attracted significant attention in biomedical engineering and targeted drug delivery. However, the current microswimmer designs are hindered by low swimming velocity and poor maneuverability. In the present study, a DNA-inspired magnetic millimeter-scale swimmer with double conical chains was designed. The millimeter-scale swimmer was fabricated by 3D printing and magnetron sputtering processes. The position of the magnetic swimmer was controlled via a rotating magnetic field generated by the Helmholtz coils. The dynamic model of the DNA-inspired magnetic swimmer was established to analyze the swimming velocity. The effects of various magnetic field strengths and fluid viscosities on the swimming velocity were investigated by theoretical, simulative, and experimental approaches. The maximum swimming velocity and the highest out-of-step frequency of the millimeter-scale swimmer were 1.6 mm/s and 34 Hz, respectively. The maneuverability of the designed millimeter-scale swimmer was verified by the W-shaped trajectory experiments.