Patent ID: 7056529

Claim:
A fusogenic vesicle, comprising: ATP at a concentration of 1 mM to 50 mM, a phospholipid which is a stable vesicle former, wherein the phospholipid is a phosphatidylcholine, and at least one unstable vesicle forming member wherein the unstable vesicle forming member is PEG or a polar lipid having the structure of the formula (I) which is X-L-Z2, wherein X is H or a head group comprising a polar group selected from the group consisting of formulas (III), (IV), (V), (VI), and (VII) L is an alkyl, and each Z is independently H, E, or the structure of formula (XI), wherein E is an alkyl or alkenyl, and when one Z is H, the other Z is not H, and wherein the vesicle has a ratio of the stable vesicle former to the unstable vesicle forming member of 1:1 to 500:1 and a fusion rate of at least 20 vesicle fusions/second.