Investigation of the Effects of Different Emollients on the Structure and Skin Moisturizing Potential of the Cosmetic Creams

SUMMARY In this study we investigated the effects of four emollients (cetearyl octanoate, decyl oleate, C12-15 alkyl benzoate and olive oil) incorporated at a concentration of 10% on the structural properties of the cosmetic oil/water (o/w) creams (creams K1-K4, respectively) as well as the in vivo effects of those creams on pH and hydration level of the healthy volunteer’s skin after a single application. Creams’ structure was investigated throughout polarization microscopy. Anisotropic structures were found, i.e. stabilization of creams’ structure was performed by forming lamellar gel-crystalline and liquid-crystalline phase, different for different creams, which was probably caused by the presence of different emollients. The effects of creams (K1-K4) on skin hydration level and pH (30, 90, 150 and 300min after single application) were examined using Multi Probe Adapter (MPA ® 9, Courage& Khazaka Electronic, Germany), with appropriate sonde, Corneometer ® CM 825 for measuring capacitance as a measure of skin moisture level, while the skin pH was measured using Skin-pH-Meter, PH 900 sonde.The results indicate that the presence of the different emollients in o/w creams (10%) led to the creams'different effects on the skin hydration level. Cream with decyl oleate leads to a good initial hydration effect and probably rapid release of large amounts of water from the cream. Creams containing both C12-C15 alkyl benzoate or olive oil had a weaker initial effect on the skin moisture, showing good occlusive properties. A cream containing 10% cetearyl octanoate showed the lowest skin hydration potential.