Hyaluronic Acid (HA) is a naturally occurring linear polysaccharide composed of repeating disaccharide units of D-glucuronic acid and N-acetyl-D-glucosamine.

It exhibits excellent biocompatibility, biodegradability, hydrophilicity, and water-retention capacity. These outstanding properties make HA one of the most widely used biomaterials in tissue engineering, regenerative medicine, drug delivery, wound healing, ophthalmology, cosmetics, and biomedical research.

A variety of functionalized HA derivatives are available for advanced applications, including thiolated hyaluronic acid (HA-SH), hyaluronic acid methacrylate (HAMA), amino hyaluronic acid (HA-NH₂), azide hyaluronic acid (HA-N₃), biotinylated hyaluronic acid, and fluorescently labeled hyaluronic acid, which can be used for hydrogel formation, bioconjugation, targeted drug delivery, and biomedical material development.