The nanoswimmers could be functionalized to deliver drugs and magnetically controlled to swim through the bloodstream to target cancer cells, for example. The research is described in ACS Nano Letters.
KurzweilAI has covered a number of similar devices, but they tend to have problems moving through body fluids, which are like molasses to something this small.
Abstract of Undulatory Locomotion of Magnetic Multilink Nanoswimmers
Micro- and nanorobots operating in low Reynolds number fluid environments require specialized swimming strategies for efficient locomotion. Prior research has focused on designs mimicking the rotary corkscrew motion of bacterial flagella or the planar beating motion of eukaryotic flagella. These biologically inspired designs are typically of uniform construction along their flagellar axis. This work demonstrates for the first time planar undulations of composite multilink
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