Abstract: Vc was encapsulated in niosomes formed by non-ionic surfactant Span and Choles via a evaporation-sonication method.To obtain a higher encapsulation efficiency,conditions including the structure of the surfactant,sonicaton,content of the drug and Cholesterol were investigated and optimized.The morphology and size of the niosomes were measured by transmission electron microscopy.The results showed that the entrapment efficiency of the niosomes for Vc could be as high as 45% under the experimental conditions o...