Abstract
Nonionic surfactant Span80 was applied in the preparation of surfactant vesicle (niosome).We revealed that themembrane of Span80 vesicle was consisted of a mixture of sorbitan ester molecules with different four kinds of alkylchains (1~4 chains). Furthermore, the ester composition in the membrane of the vesicles with constant diameter wasfound to be almost constant because the vesicle membrane was constructed by the thermodynamic self–assembly ofthe ester molecules. Thecomparision of thecharacterization between Span80 vesicles and conventional natural–lipidliposomes revealed that the Span80 vesicles had higher values in either fluidity or membrane fusion capability, andlower values in phase-transition temperature as compared with liposomes. The characteristics of Span80 vesicleswere very effective in the application of Span80 vesicles to the drug delivery system (DDS). As a result, we coulddemonstrate the potential application of Span80 vesicles from the experiments in vitroand in vivoasalternatives toconventional liposomes inDDS.
