Microscopic swimmers to break up blood vessel occlusions in the narrowest vessels have been developed at the Drexel University, Philadelphia.
Currently, such treatments are done within cath labs, but there are only a limited number of places in the body that a catheter can be pushed into.
The new swimmers may be able to drill through occlusions that would otherwise be simply inaccessible. The microswimmers are just chains of iron oxide beads strung together.
Using an external magnetic field, they are made to rotate around the main axis, causing them to swim in one direction. Rotating the magnetic field can oscillate the entire microdevice, pointing it in any direction before setting it to move forward.
The length of the chains defines the force with which the microswimmers can push against an occlusion, while different surface properties can be developed to appropriately attack the plaques causing a blockage.
At the moment, these microswimmers will be put to work in conjunction with an arterial drill developed at ETH Zurich. The idea is to position them at the site of an occlusion, make the initial impact on the plaque, following up with the drill once the material is ready for work by a larger instrument.