Droplets are tiny spherical drops of fluid, not normally considered capable of moving on their own. However, researchers from Southern Denmark University and Institute of Chemical Technology, Czech Republic have succeeded in making alcohol droplets move in water. They believe that this invention may serve as a breakthrough in potential applications of drug delivery.
Living organisms are normally considered self-moving. But, the researchers have proved that non-living entities can also move on their own.
In this experiment, Hanczyc and other members have demonstrated the ability of small alcohol droplets to move in water through a maze network. This shows that the technology can be applied to specific targets such as a carrier for chemistry finding a target to release the contents, as a lubricant targeting a lubricating area, in medicine etc.
The system itself is very simple but yet it displays sophisticated behavior.
principal investigator Martin Hanczy
Hanczyc said that the movement of droplets is initiated in the presence of salt which acts as the stimulus. The salt gradient induces energy in the droplets, enabling them to move. Like a ball rolling towards the lowest point when raised from a still surface to a hilly surface, the droplet moves downhill towards the salt gradient generated from one direction. More droplets are attracted when the salt gradient is strong.
When salt is added in a sequential manner at different locations, the droplets drift towards the salt making the system more sustainable. Moreover, the droplets have the potential to differentiate salts of different concentrations. By providing temperature stimulus externally, the process can be regulated. Also, the droplet can be made to react with the source.
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