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arXiv · 2001.06646

Dynamics of a microswimmer-microplatelet composite

Abdallah Daddi-Moussa-Ider·Maciej Lisicki·Hartmut Löwen·Andreas M. Menzel
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Abstract

Guiding active microswimmers by external fields to requested target locations is a promising strategy to realize complex transport on the microscale. To this end, one possibility consists of attaching the microswimmers to orientable passive components. Accordingly, we analyze theoretically, using a minimal model, the dynamics of a microswimmer when rigidly attached tangentially to a (significantly larger) microplatelet, here represented by a thin circular disk. On this way, we determine the flow field in the whole space induced by a Stokeslet that is located above the center of a spatially fixed rigid disk of no-slip surface conditions. Finally, we determine and analyze possible trajectories of the overall composite. To this end, the platelet is additionally endowed with a permanent magnetic moment, which allows to steer the motion of the whole composite by a homogeneous external magnetic field. As previous experimental studies suggest, related setups may be helpful to guide sperm cells to requested targets or for the purpose of coordinated drug delivery.

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Abdallah Daddi-Moussa-Ider, Maciej Lisicki, Hartmut Löwen, Andreas M. Menzel. 2020-01-18. Dynamics of a microswimmer-microplatelet composite. https://doi.org/10.1063/1.5142054

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