Dynamics of molecular transport by surfactants in emulsions

Yousr Skhiri (1) , Philipp Gruner (2) , Benoît Semin (2) , Quentin Brosseau (2) , Deniz Pekin (1) , Linas Mazutis (3) , Victoire Goust (1) , Felix Kleinschmidt (1) , Abdeslam El Harrak (1) , J. Brian Hutchison (4) , Estelle Mayot (1) , Jean-François Bartolo (1) , Andrew Griffiths (1) , Valérie Taly (1, 5) , Jean-Christophe Baret (2)

1 ISIS - Institut de Science et d'ingénierie supramoléculaires
2 MPIDS - Max Planck Institute for Dynamics and Self-Organization
3 Institute of Biotechnology, Vilnius University,
4 RainDance Technologies, Inc.
5 UMR S775

We consider the dynamics of equilibration of the chemical potential of a fluorophore in a monodisperse emulsion containing droplets with two initially different concentrations of the fluorophore. Although the exchange mechanism involves a single timescale at the droplet (microscopic) level, the organisation of the droplets determines the exchange dynamics at the population (macroscopic) level. The micelle concentration in the continuous phase and the chemistry of the fluorophore control the microscopic exchange rate while the disorder of the initial condition determines the power-law of the long timescale, recovered in a minimal analytical model. We also show here that an additive in the droplet such as Bovine Serum Albumin (BSA) acts on the microscopic exchange rate and slows down the exchange process by increasing the solubility of the fluorophore in the dispersed phase rather than by creating a viscoelastic layer at the droplet interface.

Domaines: Matière Condensée [cond-mat]; Matière Molle [cond-mat.soft]

Yousr Skhiri, Philipp Gruner, Benoît Semin, Quentin Brosseau, Deniz Pekin, et al.. Dynamics of molecular transport by surfactants in emulsions. Soft Matter, 2012, 8 (41), pp.10618. ⟨10.1039/C2SM25934F⟩. ⟨hal-02148774⟩