Hyaluronic acid is the main component of connective tissues such as human interstitial tissue, vitreous body and synovial fluid, which has important physiological functions such as water retention, maintaining extracellular space, regulating osmotic pressure, lubricating and promoting cell repair. Hyaluronic acid molecules contain a large number of carboxyl and hydroxyl groups, which are in water.

Intramolecular and intermolecular hydrogen bonds are formed in the solution, which makes it have strong water retention effect and can bind more than 400 times of its own water; At a higher concentration, its aqueous solution has obvious viscoelasticity because of the complex three-level network structure formed by intermolecular interaction. Hyaluronic acid, as the main component of intercellular matrix, directly participates in the regulation of electrolyte communication inside and outside cells, and plays a role as a filter for physical and molecular information.

Hyaluronic acid can be used as viscoelastic agent in ophthalmic intraocular lens implantation and filler in joint surgery such as osteoarthritis and rheumatoid arthritis. As a medium, it is widely used in eye drops, and also used to prevent postoperative adhesion and promote skin wound healing.