Table 1

Definition and characteristics of hyaluronan (hyaluronic acid) and hylans

Definition
Characteristics

Hyaluronan (hyaluronic acid) or sodium hyaluronate
Long, nonsulfated, straight chains of variable length

Repeating disaccharide unit of N-acetylglucosamine and glucuronic acid

Forms a randomized coil in physiological solvents

Average MW 4–5 million Da
Hylans
Crosslinked hyaluronan chains in which the carboxylic and N-acetyl groups are unaffected

MW of Hylan A is 6 million Da

Can be water-insoluble as a gel (e.g. hylan B) or membrane bound

MW, molecular weight.

Moreland Arthritis Res Ther 2003 5:54   doi:10.1186/ar623