Hyaluronic acid is classified among compounds known as glycosaminoglycans, which are polysaccharides with chains built from repeating disaccharide units. The molecule of hyaluronic acid consists of an N-acetylglucosamine molecule and a D-glucuronic acid molecule. They are linked alternately by β-(1-3) and β-(1-4) glycosidic bonds. It is a completely natural biopolymer with identical structure in humans, other vertebrates, and even bacteria. In living organisms, hyaluronic acid usually appears as a sodium salt (sodium hyaluronate). What are the properties and applications of hyaluronic acid? We will try to answer this question below.
Hyaluronic Acid – Properties
First, hyaluronic acid has hygroscopic properties. In water, its molecules can increase in volume by 1000 times, and a single HA molecule can bind about 250 water molecules. It can thus be considered as functioning like a sponge—absorbing moisture within the dermis. Such properties have led to its use as a valuable ingredient in anti-aging, protective, and moisturizing cosmetics, not only for facial care (toners, masks, creams) but also for body products (cleansing gels, lotions). It is also the most important ingredient in popular medical aesthetic products—available in non-crosslinked form (used in mesotherapy cocktails) or with varying degrees of crosslinking (serving as a filler to reconstruct tissue volume, shape lips, or smooth nasolabial folds). Hyaluronic acid used in cosmetology and aesthetic medicine is obtained via biofermentation—purified and dried into powder form, which, when mixed with water, creates a transparent gel.
Hyaluronic Acid – Applications
The most common hyaluronic acid is predominantly used in cosmetics. It is an essential component of anti-aging creams, but it is just as often, if not more, used in aesthetic medicine clinics. Anti-aging treatments typically involve injecting preparations that contain hyaluronic acid deep into the dermis. These can fill wrinkles and restore skin elasticity. These treatments are not very long-lasting, as hyaluronic acid naturally breaks down in the body. The effects usually last between 6 and 12 months, depending on the product used.
Less well-known is the use of hyaluronic acid’s properties to support healing processes in burns, skin ulcers, or wounds.
Ophthalmology is another field where hyaluronic acid is highly valued. Eye drops and contact lens solutions are made based on it. This is due to the unique water-binding capacity of the acid. Solutions containing hyaluronic acid help soothe eye irritations caused by contact lenses or dry eye syndrome. Additionally, hyaluronic acid binds harmful substances and influences the composition of the tear film.
Hyaluronic acid is also a valuable medicinal product for treating osteoarthritis and other related conditions. In such cases, injections containing the acid are administered to supplement deficiencies of certain substances.
The described acid is also used in gynecology. It relieves irritation of the intimate areas and accelerates the healing of postoperative wounds on the cervix or vulva.