Mixed monolayer behaviors of vitamin derivatives and cholesterol

The behaviors of mixed monolayers between ascorbyl palmitate (solid) and to copheryl acetate (liquid) were studied using LB film balance. The surface p ressure of tocopheryl acetate beyond collapse point remained constant, but that of ascorbyl palmitate showed deflection. The phase transitions from ex panded to condensed liquid phase in mixed monolayers were observed. These p hase transitions became dear by adding cholesterol which acts as a plastici zer in a solid monolayer and as a rigidifier in a liquid monolayer. (C) 200 1 Elsevier Science B.V. All rights reserved.