Effect of Cholesterol on the Stability of Lecithin Vesicle

The mechanism of structure transformation of vesicle was explored through TEM.The mixed monolayer at the air/water interface of lecithin and cholesterol was investigated using Langmuir balance technique.We also studied the effect of cholesterol on the structure transformation of lecithin vesicle by the method of kinetic and dynamic light-scattering.The results show that positively charged Gemini surfactant intercalates into the bilayer of negatively charged lecithin vesicle and reduces the thickness of bilayer of lecithin vesicle.The asymmetric distributing of the surfactant molecular in the vesicle led to the asymmetric thickness of the bilayer,thus resulted in the vesicle breakdown.The excess area of the mixed monolayer and kinetic results show that the mutual attraction between lecithin and cholesterol made it hard to break the lecithin vesicle by adding cholesterol.