Both HA-NB and HA-AE inks reached a similar value of G'20min = 8 kPa, suggesting a similar internal structure and crosslinking degree in the final network. HA-MA achieved a three-fold higher stiffness (G'20min = 26 kPa). A different network structure could be expected from the different polymerization mechanisms. In the chain-growth polymerization of HA-MA, MA units from the same or different chains can add to the growing macroradical and form a "cluster" of intra-and inter-molecular crosslinks (Figure ). In contrast, in the radical thiol-ene reaction each DTT dithiol crosslinker molecule can only connect to two -ene functions of the same or different chains (Figure ). Intramolecular thiol-ene reactions form loops and do not contribute to mechanical strength. Intermolecular thiol-ene reactions connect only two chains. This molecular scenario would lead to a more regular but looser thiol-ene network and, therefore a hydrogel with a lower G'. We note that similar trends have been observed in other comparative reports of NB vs MA functionalized inks. Examples in literature which study the influence of different thiol crosslinkers demonstrate that higher storage moduli could be obtained in NB hydrogels using a multivalent thiol crosslinker which can connect multiple polymer chains in contrast to DTT. In a photoinitiated radical polymerization, tuning the light intensity and illumination profile should allow control over the kinetics of the crosslinking progress. This was tested by monitoring gelation of HA-NB at different irradiance values between 1 and 6 mW cm -2 . At 6 mW cm -2 tgel was reached in less than 1 s (Figure ). Decreasing the irradiance to 1 mW cm -2 increased tgel to 5 s. The time for G' to reach the final stiffness increased from 20 to approx. 190 s.