Hyaluronic acid (/ˌhaɪ.əljʊəˈrɒnɪk/;[2][3] abbreviated as HA; conjugated group hyaluronate), also known as hyaluronic acid, is an anionic, nonsulfated glycosaminoglycan, widely Distributed in connective tissue, epithelial tissue and nervous tissue. It is unique among glycosaminoglycans in that it is