Within five seconds of applying the magnetic field, 34 out of the 40 worms in the study stopped in place, and 27 of those worms moved backward, as though retreating from a dangerous heat source. The nematodes without magnetic nanoparticles continued to wriggle forward, completely unaffected by the magnetic field.
The ultimate goal is to apply the technology to human physiology. Ion channels are basic components of virtually all living cells. The ability to open and close such channels therapeutically might provide new avenues for cancer chemotherapy and treatment of neurological and endocrine diseases.
Link (with brief video). Publication. Image credit.