Scientists used a 3D printer to create the world's smallest boat

A boat has been 3D-printed by Leiden physicists Rachel Doherty, Daniela Kraft and colleagues. From prow to stern it measures 30 micrometers, about a third of the thickness of a hair.

(CNN)Researchers have created the world's smallest boat, measuring just 30 micrometers in length, so small it could sail down a human hair.

Using an electron microscope and a high resolution 3D printer a team from Leiden University imaged and then constructed the vessel as part of research into potential designs for vehicles that could travel inside the human body, for example to administer medical treatments.
It is a tiny copy of the "Benchy" boat, a test structure often used to test the effectiveness of 3D printers.
    "We focused a laser inside a droplet," Daniela Kraft, a physicist at the Dutch university told CNN. "If we move the laser through the droplet, we write the structure that we want," she explained. "For example, if we move it in a helix, we are writing a helix."
    The boat was just one of many structures created by the researchers conducting investigations into microswimmers: small particles that can move through fluids, and be followed by a microscope.
    Biological microswimmers are microorganisms that propel themselves, including bacteria, algae and sperm.
    Synthetic, self-propelled microswimmers could have a range of uses, including delivering drugs in the human body, Kraft told CNN.