CrystalEm

The objective of project CrystalEm is to use natural active crystals to stabilize oil/water interfaces of new emulsions that could be used as innovative topical formulations on human skin. Our ambition is to use phytochemical active crystals as emulsion solid stabilizers, and their physico-chemical properties will be controlled to optimize emulsion stability. The advantage of these natural crystals concerns the immediate stabilization of the emulsion with no necessary surfactants. Herein, the influence of the crystal physico-chemical properties will be studied on the emulsion characteristics: stabilization mechanisms, type of emulsion, macroscopical and microscopical aspects, bulk and interfacial rheological behaviors, etc. Different parameters will be also varied, such as the crystal size distribution, morphology or concentration, the nature of the oil phase, the oil/water ratio or the emulsifying energy. This innovative Pickering emulsion will be studied for skin penetration of active substances, according to the properties of the chosen phytochemical crystalline form and of the active ingredient used in the oily phase. Altogether, the project consists of three main parts: 1) choice and preparation of natural active crystals with controlled physico-chemical properties; 2) use of these active crystals for the formulation, stabilization and optimization of oil-in-water emulsions; 3) validation of the biological properties of the emulsions in vitro using cutaneous culture models, and establishment of a proof of concept of pharmacological effectiveness in inflammatory dermatoses.