Biohybrid and Bioinspired Magnetic Microswimmers

Abstract

Many motile microorganisms swim and navigate in chemically and mechanically complex environments. These organisms can be functionalized and directly used for applications (biohybrid approach), but also inspire designs for fully synthetic microbots. The most promising designs of biohybrids and bioinspired microswimmers include one or several magnetic components, which lead to sustainable propulsion mechanisms and external controllability. This Review addresses such magnetic microswimmers, which are often studied in view of certain applications, mostly in the biomedical area, but also in the environmental field. First, propulsion systems at the microscale are reviewed and the magnetism of microswimmers is introduced. The review of the magnetic biohybrids and bioinspired microswimmers is structured gradually from mostly biological systems toward purely synthetic approaches. Finally, currently less explored parts of this field ranging from in situ imaging to swarm control are discussed.

Rotibot: Use of Rotifers as Self‐Propelling Biohybrid Microcleaners

“…A major challenge in the field is to translate and scale up these microrobotic applications to relevant environmental settings by addressing limitations associated with toxic chemical fuels, short time span, and the small domain operation of externally‐actuated microrobots . One plausible solution is to develop biohybrid microrobots that integrate self‐propelling microorganisms with functionalized synthetic nanostructures. The current generation of biohybrid platforms is based primarily on flagellated microorganisms which survive only in delicate living conditions and may not provide sufficient fluid mixing for enhancing decontamination processes.…”

Chemo‐ and Magnetotaxis of Self‐Propelled Light‐Emitting Chemo‐electronic Swimmers

“…These results are clear evidence of the presence of an intrinsic magnetic moment in the sole diode, which allows studying the magnetotactic behavior of the designed swimmers. Magnetotaxis is the phenomenon in which a particle with a permanent magnetic moment orientates itself towards the magnetic field of the earth or with respect to an external magnetic field . This was first observed for iron‐rich magnetotactic microorganisms, and then the same concept was used to develop magnetotactic micro‐ and nano‐swimmers .…”

Chemo‐ and Magnetotaxis of Self‐Propelled Light‐Emitting Chemo‐electronic Swimmers

“…These results are clear evidence of the presence of an intrinsic magnetic moment in the sole diode, which allows studying the magnetotactic behavior of the designed swimmers. Magnetotaxis is the phenomenon in which a particle with a permanent magnetic moment orientates itself towards the magnetic field of the earth or with respect to an external magnetic field . This was first observed for iron‐rich magnetotactic microorganisms, and then the same concept was used to develop magnetotactic micro‐ and nano‐swimmers .…”