"Nature has some million years of experience. It seems like a good idea to make use of this fact", says Holger Stark. Indeed, the Professor for theoretical physics at the Technical University of Berlin is engaged with one of nature's domains, which other people might dread: Gut bacteria and salmonella. He analyzes the movement of those microscopically small organisms in aqueous environments. Following their example, tiny machines with the aptitude to work inside the humanbody could be built.
"A single bacterium with its spiral filaments, driven by a rotating engine merely a few nanometers small, is a marvel of nature. Understanding its mechanisms of movement helps us build microscopically small robots that, among other purposes, could be sent on a journey through a body's blood vessels", he illustrates his visions for the future. Those micro machines could be directed to repair cells and vessels or transport medication to exactly where it is needed.
"The knowledge about how these bacteria move and how this movement is influenced by glutinous surroundings opens up a variety of possibilities to act on the living bacteria themselves", says Reinhard Vogel, the project's research assistant. Hygiene in hospitals could possibly benefit from those insights. "Due to their swimming motions, bacteria accumulate on smooth surfaces. Preventing this could reduce the risk of infections through catheters or prostheses."
What the researchers already know about the mechanisms of movement of the microscopically small swimmers is that in their cell's membrane rotational engines exist, that propel spiral filaments or flagella. "Those conjoin into a rotating bundle and therefore generate propulsion", explains Vogel. "The steering is simple: One or another filament sheers out of the bundle when the engine's rotational direction changes. This makes the entire bacterium fishtail and eventually causes a change in direction."