SIENTIFIC INFORMATION / HYALURONIC ACID
 Hyaluronic Acid
  Molecular structure of hyaluronic acid:
Hyaluronic acid molecules are non-sulfated glycosaminoglycans: polysaccharides which are present in the extracellular matrix of the dermis and epidermis. They are synthesised by keratinocytes (epidermis) and fibroblasts (dermis).
Hyaluronic acid molecules are non-species- and non-tissue-specific so there is little risk of allergy.
Hyaluronic acid molecules exist in a free state with no covalent link to any protein. Hyaluronic acid molecular structure is three-dimensional (3D), occupying a very large volume for its molecular weight. The molecules form a dense, complex mesh.
They appear in the form of a long, flexible, helicoidal ribbon which can be tens of micrometres long. In the extracellular matrix, the molecule may be folded up on itself and take on many different conformations. The negatively charged residues repel one other, causing the molecule to occupy a large volume.
The water-retaining capacity of hyaluronic acid helps maintain the cohesion and structure of the dermis. 1g of hyaluronan can absorb up to 1l of water.
It hydrates the skin, making it supple and firm and providing visco-elastic properties.
In order to increase the lifespan of Hyaluronic Acid in the dermis, a cross-linking stage is carried out using BDDE, one of the least toxic cross-linking agents on the beauty product market. This involves linking macromolecules of hyaluronic acid together with "bridges" which makes them more resistant to being broken down, particularly by hydroxyl radicals.
Hydration (non-cross-linked)
Filling and Volume (cross-linked)
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