Controlled Propulsion of Two-Dimensional Microswimmers in a Precessing Magnetic Field

Open access
Date
2018-06-14Type
- Journal Article
Citations
Cited 29 times in
Web of Science
Cited 29 times in
Scopus
ETH Bibliography
yes
Altmetrics
Abstract
Magnetically actuated micro‐/nanoswimmers can potentially be used in noninvasive biomedical applications, such as targeted drug delivery and micromanipulation. Herein, two‐dimensional (2D) rigid ferromagnetic microstructures are shown to be capable of propelling themselves in three dimensions at low Reynolds numbers in a precessing field. Importantly, the above propulsion relies neither on soft structure deformation nor on the geometrical chirality of swimmers, but is rather driven by the dynamic chirality generated by field precession, which allows an almost unconstrained choice of materials and fabrication methods. Therefore, the swimming performance is systematically investigated as a function of precession angle and geometric design. One disadvantage of the described propulsion method is that the fabricated 2D swimmers are achiral, which means that the forward/backward swimming direction cannot be controlled. However, it has been found that asymmetric 2D swimmers always propel themselves toward their longer arm, which implies that dynamic chirality can be constrained to be either right‐handed or left‐handed by permanent magnetization. Thus, the simplicity of fabrication and possibility of dynamic chirality control make the developed method ideal for applications and fundamental studies that require a large number of swimmers. Show more
Permanent link
https://doi.org/10.3929/ethz-b-000271851Publication status
publishedExternal links
Journal / series
SmallVolume
Pages / Article No.
Publisher
Wiley-VCHSubject
chirality; low Reynolds number; microswimmers; nanomotors; precessing magnetic fieldsOrganisational unit
03627 - Nelson, Bradley J. / Nelson, Bradley J.
More
Show all metadata
Citations
Cited 29 times in
Web of Science
Cited 29 times in
Scopus
ETH Bibliography
yes
Altmetrics