Influence of lipid vesicle composition and surface charge density on vesicle adsorption events: a kinetic phase diagram

Lipid vesicle adsorption on a solid surface, from a bulk liquid solution, results in different final situations on the surface depending on the vesicles' composition, properties of the solution (pH, ion types, and concentration), and surface properties. The main alternative outcomes of the adsorption event are (i) a lipid bilayer with vesicle rupture immediately upon the adsorption event or (ii) bilayer formation only at and after a critical vesicle coverage, (iii) adsorption of intact vesicles, or (iv) repulsion (no adsorption). We have simulated these different events for the case of vesicles consisting of pure neutral (zwitterionic) lipids and mixtures of neutral and positive or negative lipids, keeping the bulk conditions fixed, and have compiled the different resulting lipid structures on the surface as a function of vesicle composition and surface charge density, in a kinetic phase diagram.