title: Dynamics of vesicle unbinding under axisymmetric flow.
abstract: The competition between adhesion and external flow to unbind settled vesicles from substrates is investigated. An experimental setup is developed to apply a hydrodynamic pulling force in the range of a few piconewtons to a vesicle with retained axisymmetry. In the limit of a small excess of membrane area, vesicles are found to transit during unbinding from a process of fluid film thickening at constant contact area to a finite-time process of contact radius drop to zero with an exponent 1/2. Both characteristic times vary linearly with the inverse flow rate. On the contrary, deflated vesicles under a moderate pulling force exhibit a decrease of contact area at a constant film thickness before a film thickening.
authors.affiliation: IRPHE, Aix-Marseille Université, CNRS UMR6594, Centrale Marseille, 13384 Marseille Cedex 13 France.
authors.forename: Sunita
authors.initials: S
authors.lastname: Chatkaew
authors.forename: Marc
authors.initials: M
authors.lastname: Georgelin
authors.forename: Marc
authors.initials: M
authors.lastname: Jaeger
authors.forename: Marc
authors.initials: M
authors.lastname: Leonetti
mesh_terms: D012212:Rheology; D013997:Time Factors; D053835:Unilamellar Liposomes / Q000378:metabolism*
chemical_list: D053835:Unilamellar Liposomes