World’s smallest propeller measuring just 70 nm wide by 400 nm long, 100 times smaller than the diameter of a human blood cell, could be used for targeted drug delivery.
Scientists created tiny helical nanopropeller that are only 70 nanometers (billionths of a meter) in length, small enough to maneuver inside the human body and possibly inside human cells.
The research team at the Max Planck Institute for Intelligent Systems in Germany, led by Dr. Peer Fischer, has made the tiny propellers from a filament of silica and nickel.
The microscopic propeller needs to be controlled externally by a weak rotating magnetic field. It can successfully navigate through a material found throughout the human body, called hyaluronan gel.
According to the team:
“We show that the nanoscrews will move through high-viscosity solutions with comparable velocities to that of larger micropropellers, even though they are so small that Brownian forces suppress their actuation in pure water. When actuated in viscoelastic hyaluronan gels, the nanopropellers appear to have a significant advantage, as they are of the same size range as the gel’s mesh size. Whereas larger helices will show very low or negligible propulsion in hyaluronan solutions, the nanoscrews actually display significantly enhanced propulsion velocities that exceed the highest measured speeds in Newtonian fluids. The nanopropellers are not only promising for applications in the extracellular environment but small enough to be taken up by cells.”