The epidermis is the outer layer of skin. The epidermis contains 5 layers. The top layer of the epidermis, the stratum corneum (horny layer), is made of dead, flat skin cells that shed about every two (2) weeks. Keratinocytes adhere to one another through desmosomes. These protein-based cell “connectors” will eventually be dissolved by the skin’s own proteases (protein decomposing enzymes). Healthy skin usually has a natural balance between cell proliferation in deeper skin layers and desquamation on the skin surface. Desquamation tends to slow down as we age. It is a fact that increased cell turnover in the epidermis results in a smoothing out of the surface of the skin; therefore the potential for proteases in cosmetics application is obvious. They intervene in the bio-chemical mechanism of cell discharge – in the same way as the skin’s own enzymes do.

However, one major obstacle exists when it comes to using proteases in cosmetics; their instability. These protein types are highly unstable in an aqueous environment. They decompose and break down into smaller particles, therefore losing effectiveness. Our chosen protease, Subtilisin, has overcome these problems with the development of a stabilized protease in the form of insoluble crystals which cannot be absorbed by the skin. Subtilisin is the proteases used in the Skin Refining Enzyme Peel, which mimics the skin's own enzymes that dissolves the desmosomes between the horny layer.