Ascending air bubbles in protein solutions

C. Ybert (1) , J.-M. Di Meglio (1)

1 ICS - Institut Charles Sadron

We report measurements of the ascending velocity of air bubbles in protein (bovine serum al-bumin) solutions. We show that, because of the protein molecules adsorbed on their surface, the terminal ascending velocity of bubbles is strongly reduced compared to the terminal velocity in pure water: protein-covered bubbles behave hydrodynamically as solid spheres. From the evolution of the ascending velocity with time, we can derive the amount of protein needed to immobilize the bubble interface which is 0.5 mg m −2 , i.e. only one fifth of the amount adsorbed at equilibrium in the range of used bulk concentrations .

Domaines: Matière Molle [cond-mat.soft]; Dynamique des Fluides [physics.flu-dyn]

C. Ybert, J.-M. Di Meglio. Ascending air bubbles in protein solutions. The European Physical Journal B: Condensed Matter and Complex Systems, 1998, 4 (3), pp.313 - 319. ⟨10.1007/s100510050385⟩. ⟨hal-01628735⟩