Congener-dependent conformations of isolated rhamnolipids at the vacuum-water interface: A molecular dynamics simulation

Abstract Hypothesis Molecular dynamics simulation can be used to differentiate between the adsorption properties of rhamnolipid congeners at a vacuum-water interface. Experiments Adsorption five with differing alkyl chains (two C10 chains, two C14 or mixed C14C10 and C10C14), number rhamnose rings (mono- di-) carboxyl group charge (non-ionic anionic) are simulated Findings All rhamnolipids adsorb in interfacial region groups closer water phase, vacuum but adsorbed conformations. Headgroups uncharged show preferred conformations, closed partially open. Di-rhamnolipid has low proportion conformation, due steric constraints second pyranose ring. Charged strong preference for headgroup For equal lengths (C10C10, C14C14) distribution chain tilt angles is similar both. Where unequal (C14C10, C10C14) one greater tendency towards phase (>90°). The order parameter shows they disordered Together, these results congener-dependent conformation differences suggesting will have surface-active oil-water interfaces.