Self-Assembly and Antioxidant Properties of Octanoyl-6-O-ascorbic Acid

Vitamin C acts as a powerful radical scavenger, and can be used as a convenient antioxidant agent in aqueous media. To extend its properties to nonaqueous environments, alkanoyl-6-O-ascorbic acid esters with different chain lengths were synthesized, and their micellar and antioxidant properties were investigated by surface tension, viscosity, light scattering, neutron scattering, oxygen uptake, and UV/VIS spectra. According to our results, octanoyl-ascorbic acid forms nearly spherical micelles in water solutions above a cmc of about 6 x 10(-3) mol/L at 30 degrees C, while decanoyl- and dodecanoyl-ascorbic acid are poorly soluble in water. No matter how long the hydrophobic chain is, all these esters show the same antioxidant activity as vitamin C and other natural products.