Self-moving droplets to deliver drugs in future

Researchers have found a way to make alcohol droplets move on their own, in a life-like way, a finding that could be used in future to deliver medicines to targeted areas.

Droplets are simple spheres of fluid, not normally considered capable of doing anything on their own.

To be able to move on its own - to be self-moving - is a feature normally seen in living organisms.

The self-moving droplets can be led to certain targets and, therefore, they may be used as a technology to physically move chemistry to a place where it is desired.

"For example, the droplet can act either as a lubricant, targeting an area that needs lubrication. Or the droplet can act as a carrier for chemistry that can find a target destination and release its content, such as flavouring or medicine," said principal investigator Martin Hanczyc from the University of Trento in Italy.

The droplets start to move when they sense salt in their environment, the researchers said.

"Salt is the stimulus that makes them move. They move because the salt gradient provides a different energy landscape," Hanczyc added.

It is like taking a ball that is laying still on a flat surface and then suddenly make the surface hilly. The ball will roll to the lowest accessible point. That is what the droplet is doing.

"Without a salt gradient every direction in which a droplet might move looks the same (flat). But with a salt gradient coming from one direction the droplet can move energetically downhill into the salt gradient," Hanczyc explained.

Stronger salt concentrations will attract the droplet more, he pointed out.

The study appeared in the journal Langmuir.