摘要 |
A method of forming liposomes with a uniform size distribution, and an average size of about 300 nm or less. Vesicles-forming lipids are dissolved in a water-miscible solvent, such as ethanol, and an aqueous medium is added to a water:solvent ratio at which lipid assembly first occurs. The water:solvent ratio is raised, under conditions which maintain the volume of the mixture substantially constant, until uniform-size liposomes are formed. The average size of the liposomes can be selectively varied by changing the ionic strength and lipid composition of the mixture. In one embodiment, the method is used to produce small unilamellar vesicles. Also disclosed are suspensions of liposomes which have a narrow, substantially symmetrical size distribution in a selected size range.
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