ABSTRACT
Drug-loaded liposomes are now being used in the clinic for different indications. This implies that these liposome formulations are stable for prolonged periods of time when properly stored. Besides the retention of the encapsulated agent, there are two stability aspects when considering therapeutic systems containing liposomes: (i) the liposome components may degrade by hydrolysis and oxidation, and (ii) the physical structure of the liposomes may be affected, by changes within the bilayer, aggregation, or fusion. Chemical changes in the bilayer-forming molecules may affect physical stability; e.g., if the phospholipids lose one of their acyl chains (turn into their lysoforms), the bilayer structure is affected.
