Under magnet’s sway, fluids form simple structures
Droplets wiggle, split and coalesce into simple and dynamic configurations
By Andrew Grant
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Dollops of magnetic fluid can assemble themselves into both simple structures and constantly changing complex formations, researchers report in the July 19 Science.
In nature, molecules such as proteins can autonomously warp and fold themselves into new arrangements. Scientists want to create self-assembling synthetic structures that are as dynamic and versatile as the natural ones that drive life.
Physicist Jaakko Timonen at Aalto University in Finland and colleagues figured they could do that with ferrofluids, liquids that contain suspended magnetic nanoparticles and behave in strange ways when exposed to magnetic fields. The researchers placed a droplet of ferrofluid atop a nonstick surface and gradually moved a magnet toward the surface from below. The strengthening magnetic field caused the droplet to split into simple, evenly spaced daughter droplets.