An Ionic Polymer Bead-supported Lipid System Using Naturally Occurring Phospholipids.
ABSTRACT
Spherically supported bilayer membranes on cationic polymer beads were
prepared from naturally occurring phospholipids (phosphatidylcholine (PC)
and phosphatidylserine (PS)). The amount of phospholipids bound to the
cationic polymer beads from the liposomal suspensions of various lipid
compositions increased with increases in anionic PS. Confocal fluorescence
microscopic observations with a fluorescence membrane probe indicated that
the phospholipid molecules in the phospholipid-bead complexes were along
the surface of the beads. Negatively charged trypan blue dye was preferably
bound to the phospholipid-free beads by electrostatic attractive interaction,
but was excluded from the phospholipid-bead complexes due to the bilayer
membrane structure formed on the beads. This method could provide a better
mimetic of biological membranes in comparison to physically unstable conventional
liposomes.