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Updated: May 15, 2026

Aqueous Droplets Used as Enzymatic Microreactors and Their Electromagnetic Actuation
Published on: August 28, 2017
Ultra-quick dynamics and acrobatics of viscous marbles
Auriane Huyghues Despointes1, Yui Takai1,2, Shoko Ii1
1Physique et Mécanique des Milieux Hétérogènes, UMR 7636 du CNRS,PSL Research University, ESPCI, Paris, France.
None:
Non-wetting viscous drops are unusually quick compared to wetting ones, owing to the conjunction of non-wetting (which minimizes the contact with the substrate) and rotation (which minimizes the dissipation inside the liquid). Here, we report the existence of a threshold in driving force above which the speed of these objects increases about tenfold compared to previous models and experiments. We find that this effect is due to a dynamic reduction of the contact, that minimizes even more the interaction with the substrate but can also render the dynamics non-stationary - a consequence of the geometrical transformations of fast revolving drops. Paradoxically, viscosity enables this regime by impeding rapid contact equilibration, thereby reducing substrate interactions in fast-moving drops.
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