HA is a non-sulphated glycosaminoglycan present in the extracellular matrix and widely used in biomedical applications. It can be chemically functionalized at the carboxylic acid and alcohol groups on the disaccharide units with photocrosslinkable groups for hydrogel formation. , HA of different molecular weights is commercially available and solutions with different viscosities can be formulated by adjusting the molecular weight and the polymer concentration.