Hyaluronic Acid Filler Impurities

Generally, hyaluronic acid (HA) is distributed in a powdered form and is divided into several grades based on its purity and other factors. Typically, 1,4-butanediol diglycidyl (BDDE) is used as a crosslinking agent in addition to other substances such as PEG or DVS. The addition of powdered HA and a crosslinking agent results in the formation of HA fillers, and the manufacturing process involves several other steps.