Magnetotaxis Enables Magnetotactic Bacteria to Navigate in Flow

• DOI: 10.1002/smll.201702982
• Publication Date: 2017-12-05T10:39:03Z
• Authors: Saeed Rismani Yazdi; Reza Nosrati; Corey A. Stevens; David Vogel; Peter L. Davies; Carlos Escobedo
• Keywords: Magnetotactic Bacteria

Magnetotactic bacteria (MTB) play an important role in Earth's biogeochemical cycles by transporting minerals aquatic ecosystems, and have shown promise for controlled transport of microscale objects flow conditions. However, how MTB traverse complex environments is not clear. Here, using microfluidics high-speed imaging, it revealed that magnetotaxis enables directed motion Magnetospirillum magneticum over long distances velocities ranging from 2 to 1260 µm s-1 , corresponding shear rates 0.2 142 -a range relevant both biomedical applications. The ability overcome a current influenced the flow, magnetic field, their relative orientation. can 2.3-fold higher when swim perpendicular as compared upstream, latter orientation induces drag. results indicate threshold drag 9.5 pN, velocity 550 where counterdirectional flow. These findings bring new insights into interactions with while suggesting opportunities vivo applications microbiorobotics targeted drug delivery.