Drugs solubilization in ascorbyl-decanoate micellar solutions

Alkanoyl-6-O-ascorbic acid esters are obtained upon esterification of ascorbic acid's primary hydroxyl groups with fatty acids. Being more hydrophobic than vitamin C, they dissolve in lipophilic media, and behave as surfactants in water, where they produce micellar aggregates or spreading monolayers, depending on the side chain length. These amphiphiles keep the same antioxidant activity of vitamin C, and can be used for solubilization and protection of hydrophobic species from oxidative degradation. In this paper we report a study on the micellar aggregates formed by decanoyl-6-O-ascorbic acid in water, through surface tension, conductivity, and solubility experiments, and on its coagels produced at low temperatures, by means of differential scanning calorimetry and scanning electron microscopy. Solubilization of some hydrophobic molecules (phenacetin, danthron, and griseofulvin) in ascorbyl-decanoate (ASC10) micelles confirms that the supramolecular assemblies significantly enhance the solubility of these drugs in the liquid phase.