Figure 1

Flagellated nanoparticles and magnetic actuation system. (a) Diagram of flagella repolymerization: (A) bacteria are cultured; (B) centrifuged and resuspended in buffer; (C) vortexed to separate flagellar filaments; (D) and isolated through ultracentrifugation; (E) depolymerized by heating; (F) a small portion is repolymerized in to short fragments (seeds); (G) the seeds are added to the original solution of flagellin and repolymerization is carried out for 72 hours. (b and c) SEM images of flagella attached to magnetic particles (indicated by white arrows); Scale bar is 1 µm in (b) and (c) 0.5 µm (d) Diagram of experimental coil system (e) Schematic of flagellar nano swimmer’s motion and the rotating magnetic field.