Phase diagram for an osmotically stressed lipids vesicle

Vesicles have been observed to explode when placed under sudden and extreme osmotic imbalance. This recently discovered behavior holds exciting opportunities for new directions in artificial cell systems, nanoparticle transport, and understanding the fundamental mechanisms of osmoregulation in living cells. Yet not all osmotic shocks will induce vesicle explosion, with some scenarios leading to simple engorgement and others causing cyclic swelling with transient pore formation. Under what conditions vesicles will transition to explosion and how this is situated in relation to other known behavioral regimes was previously unknown. In this talk we introduce a comprehensive model of vesicle osmotic response to construct the lipid vesicle phase diagram, accounting for vesicle explosion. We demonstrate the pivotal and previously unrecognized role of spontaneous curvature in determining vesicle outcomes. We present experimental evidence supporting the proposition that through reckoning with the role of spontaneous curvature, vesicle response across conditions can be unified into a single predictive model. Finally, we discuss crucial membrane and environmental properties that determine vesicle behavior. This work understanding the energy landscape of vesicle and the conditions that influence its form hold the potential in manufacturing vesicles to produce desired and precise behavioral qualities as well as reveal the processes that underlie the essential mechanisms of life.