How to stabilize phospholipid liposomes (using nanoparticles).

The simple strategy of mixing phospholipid liposomes with charged nanoparticles and using sonication to mix them at low volume fraction produces particle-stabilized liposomes that repel one another and do not fuse. Subsequently, the volume fraction can be raised as high as approximately 50%, reversibly, still without fusion. In studies of liposome longevity, we verified the stability of particle-stabilized liposome suspensions with volume fraction up to 16% for up to 50 days, the longest period investigated. Fluorescent dyes were encapsulated within the particle-stabilized liposomes, without leakage. Although these particle-stabilized liposomes were stable against fusion, approximately 75% of the outer liposome surface remained unoccupied. This opens the door to using particle-stabilized liposomes in various applications.