Effect of sucrose on the structure of a cubic phase formed from a monoolein/water mixture

The effect of sucrose on the structure of molecular assemblies formed in an MO/H2O mixture has been Studied using a small-angle X-ray scattering method. It was found that the phase transition Ia3d -> Pn3m -> H-II occurs with increased sucrose concentration in the mixture with the composition 70 wt% MO at 20 degrees C. This structural change induced by sucrose addition would be ascribed to a cosmotropic property of sucrose, which leads, to the dehydration of the MO head group and hence cause a decrease in the effective area occupied by the MO molecule at the polar/apolar interface, which facilitates the formation of Molecular assemblies with a high curvature for the reversed liquid-crystal mesophase. (c) 2005 Elsevier Inc. All rights reserved.