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Updated: Jul 16, 2026
07:08
Film Control to Study Contributions of Waves to Droplet Impact Dynamics on Thin Flowing Liquid Films
Published on: August 18, 2018
Bacterial turbulence drives interfacial waves and shape dynamics in phase-separated droplets
Kan Chang1, Yulin Li2, Ming Yuan1
1School of Physics and Astronomy, Institute of Natural Sciences and MOE-LSC, Shanghai Jiao Tong University, Shanghai, China.
Nature Communications
|July 14, 2026
Summary
Active bacterial turbulence within liquid droplets drives their shape and dynamics, leading to novel morphologies like filaments and enhanced motility. This reveals how internal forces reshape multiphase fluid systems.
Area of Science:
- Physics
- Biology
- Materials Science
Background:
- Liquid-liquid phase separation is crucial in various scientific fields.
- Active components, like bacteria, are increasingly studied for their role in phase separation dynamics.
- Understanding how active stresses affect droplet interfaces and dynamics is limited.
Purpose of the Study:
- To investigate how internally generated active stresses from bacteria influence the dynamics and morphology of phase-separated droplets.
- To explore the transmission of bacterial active stress to droplet interfaces.
- To understand the resulting three-dimensional droplet dynamics.
Main Methods:
- Encapsulating motile bacteria within phase-separated aqueous droplets.
- Controlling active stress by varying bacterial density.
- Observing interfacial fluctuations and droplet deformations at different bacterial densities.
Main Results:
- At low bacterial density, scale-dependent interfacial waves were observed, indicating an effective inertial response.
- At high bacterial density, droplets deformed significantly, exceeding the Plateau-Rayleigh instability threshold.
- Novel bacteria-scale filament formation and enhanced droplet motility and coarsening were observed.
Conclusions:
- Active bacterial stresses can fundamentally reshape the morphology and dynamics of multiphase systems.
- This study provides new insights into the physics of internally driven phase-separated fluids.
- Bacterial turbulence acts as an internal driver for droplet interface dynamics.
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