Skin Constituents as Cosmetic Ingredients. Part III: A Molecular Modeling Study of Bio‐Mimetic Monoglycerides Behavior at the Squalene‐Water Interface

The molecular modeling study described here revisits the experimental work that focused on the interfacial properties of different monoglycerides at the squalene/water interface.1 2 The use of molecular modeling software programs allowed the determination of new parameters and provided a better understanding of the behavior of those amphiphilic molecules at the interface of the two non‐miscible liquids. Each monoglyceride studied has been characterized by an HLVB value; the curvature radius, R_c; the area of the droplets formed, A_G; the number of monoglyceride molecules required to form a droplet, N; and the distance separating surfactant molecules at the interface, d.

The analysis of those different parameters shows that short hydrocarbon chain monoglycerides, such as those having one or more unsaturations and those having a grafted hydroxyl function in the middle of their chain, are excellent surfactants. These configurations promote the efficient reduction of surface tension existing at the squalene/water interface.

Keywords:

• Monoglycerides
• surfactants
• molecular modeling
• HLVB
• curvature radius
• Micelle area
• aggregation number
• intermolecular distance

Acknowledgments

The authors thank Dr. A. Cagna, B. Delorme, and C. Boinon from IT Concept as well as Dr. P. Brochette, Dr. Lars Norlen, M^s. V. Walters, and M. P. Olivier for their help and collaboration.