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

Abstract

<p>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. </p>