Controlling the movement of active droplets in emulsion using chemically reactive magnetic microparticles

There has been significant progress in the methods for synthesizing active emulsions, but the problem of controlling the motion of active droplets in space and time is still an extraordinary challenge. Here, we demonstrate a method for controlling the motion of active droplets using magnetic chemically reactive microparticles. This method is based on the principle that if the motion of active droplets in an emulsion is driven by the Marangoni flow and when chemical reactions occur on the surface of microparticles compounds are formed that can affect the interfacial tension, then the motion of the droplets can be controlled using such microparticles.