Hyaluronic acid(HA) is a straight chain macromolecular mucopolysaccharide composed Of repeat disaccharide units of glucuronic acid and N-acetylglucosamine. It widely consists in the extracellular space of human and animal tissue, vitreum, umbilical cord, skin joints synovia and cockscomb, etc. The commercial HA is commonly a sodium salt, called sodium hyaluronate, habitually called hyaluronic acid. HA is a new biological at home and abroad. Its molecular weight is from several ten thousand to several million. It's aqueous solution has outstanding moisture keeping ability, high viscoelasticity and lubricity. It is widely used in cosmetics, pharmacy and health and beauty food.

Hyaluronic acid exists naturally in all living organisms and is a unversal components of the spaces between the cells of body tissues (extracellular space) and eye vitreous body, it has special function: (1)Moisturizing effect and Nutritional ingredient (2)Thickening, Lubricating and membrance-forming (3) Sun-screening and restoration of skin trauma