Light-adaptive motility in self-propelled microswimmers

In nature, microorganisms such as bacteria have developed means to efficiently maneuver their environments, seek nutrients, and avoid toxins by responding to different environmental cues. In artificial systems, however, precise control over transport on the microscale remains a difficult task to achieve as directed motion is strongly hindered by random reorientation events caused by diffusion. For many applications, including drug delivery systems or environmental remediation it would be desirable to have artificial microswimmers with capabilities similar to their biological counterparts.

We're currently developing a platform of microswimmers with adaptive motility to tackle these limitations. Using silica-titania Janus Particles, powered by electric fields, we're able to control the motility by making use of the titania’s property to change its conductivity in response to different illumination conditions. Through light modulation in space and time, we maintain control over their movement, opening up possibilities to emulate many of the traits observed in biological microswimmers.
We are looking for a motivated MSc student who wants to contribute to the development of this novel platform and work together with a dynamic and interdisciplinary. Specifically, the student will work on:
• Characterising the behaviour of the particles moving under different frequency regimes
• Creating a new generation of light-responsive microswimmers using microfabrication techniques
• Further developing a real-time particle tracking code to adapt the light modulation based on particle positions

It is possible to work on this project in the scope of a master thesis or a project starting as soon as possible or upon agreement. If you're interested in contributing to this project, feel free to reach out to Ueli Töpfer () to learn more about the project.