To investigate the crosslinking kinetics of HA-X hydrogels, we used oscillatory shear rheology and in situ illumination at 400-500 nm to initiate photopolymerization. Figure shows the evolution of the shear moduli with light exposure time. Table shows the comparative values of the gelation time tgel and the value of the shear modulus at full crosslinking (G'20min) extracted from the curves.