Influence of vitamin E acetate and other lipids on the phase behavior of mesophases based on unsaturated monoglycerides.

The phase behavior of the ternary unsaturated monoglycerides (UMG)–dl-α-tocopheryl acetate–water system has been studied. The effects of lipid composition in both bulk and dispersed lyotropic liquid crystalline phases and microemulsions were investigated. In excess water, progressive addition of dl-α-tocopheryl acetate to a binary UMG mixture results in the following phase sequence: reversed bicontinuous cubic phase, reversed hexagonal (HII) phase, and a reversed microemulsion. The action of dl-α-tocopheryl acetate is then compared to that of other lipids such as triolein, limonene, tetradecane, and dl-α-tocopherol. The impact of solubilizing these hydrophobic molecules on the UMG–water phase behavior shows some common features. However, the solubilization of certain molecules, like dl-α-tocopherol, leads to the presence of the reversed micellar cubic phase (space group number 227 and symmetry Fd3m) while the solubilization of others does not. These differences in phase behavior are discussed in terms of...