Direct measurement of interaction forces between charged multilamellar vesicles†

Soft Matter. 2014 Oct 21;10(39):7769-80. doi: 10.1039/c3sm52785a. Epub 2014 Aug 21.

Abstract

Depletion-attraction induced adhesion of two giant (∼ 40 μm), charged multilamellar vesicles is studied using a new Cantilevered-Capillary Force Apparatus, developed in this laboratory. The specific goal of this work is to investigate the role of dynamics in the adhesion and de-adhesion processes when the vesicles come together or are pulled apart at a constant velocity. Hydrodynamic effects are found to play an important role in the adhesion and separation of vesicles at the velocities that are studied. Specifically, a period of hydrodynamically controlled drainage of the thin film between vesicles is observed prior to adhesion, and it is shown that the force required to separate a pair of tensed, adhering vesicles increases with increasing separation velocity and membrane tension. It is also shown that the work done to separate the vesicles increases with separation velocity, but exhibits a maximum as the membrane tension is varied.

Publication types

  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, Non-P.H.S.