Abstract: A lipid vesicle comprising a phospholipid which is a stable vesicle former and at least one unstable vesicle forming member, wherein the unstable vesicle forming member is selected from the group consisting of a polar lipid which is not a stable vesicle former, a PEG, a raft former and a fusion protein is provided. The vesicle can further comprise a biomolecule, such as for example ATP. Methods of using the vesicle for delivery of biomolecules are also provided.

Abstract: Preserved fusogenic vesicles are disclosed that include a saccharide, a fusogen, and a first polar phospholipid that is a stable vesicle former. The preserved fusogenic vesicles have a fusion rate of at least 20 vesicle fusions per second when re-hydrated. Methods of preserving fusogenic vesicles also are disclosed. Unexpectedly, after re-hydration the preserved fusogenic vesicles may transfer substantially more ATP through a cell membrane than unpreserved fusogenic vesicles.