Interaction and adhesion of vesicles: Coupling between attractive interactions and bilayer membrane flexibility

A simple model for vesicle interaction and adhesion, due to nonspecific col loidal forces, is presented. It is shown that possible coupling with the de formations of the bilayer lipid membrane may substantially enhance the effe ct of the attractive forces. Thus, the presence of a water core in the vesi cle interior decreases the strength and the range of the van der Waals attr action, but the deformation of the Lipid bilayers may compensate this effec t. to a certain extent. Therefore, the total attractive energy (in the abse nce of specific interactions or other sources of attraction hire depletion forces, etc.) could be due to coupling between the van der Waals and bendin g elasticity forces. The presence of excess line energy may lead to the app earance of a barrier in the interactions. As a result, a complex energy ver sus distance profile could be observed.