Extrusion-Based Bioprinting through Glucose-Mediated Enzymatic Hydrogelation

Abstract

We report an extrusion-based bioprinting approach, in which stabilization of extruded bioink is achieved through horseradish peroxidase (HRP)-catalyzed cross-linking consuming hydrogen peroxide (H₂O₂) supplied from HRP and glucose. The bioinks containing living cells, HRP, glucose, alginate possessing phenolic hydroxyl (Ph) groups, and cellulose nanofiber were extruded to fabricate 3D hydrogel constructs. Lattice- and human nose-shaped 3D constructs were successfully printed and showed good stability in cell culture medium for over a week. Mouse 10T1/2 fibroblasts enclosed in the printed constructs remained viable after 7 days of culture. It was also able to switch a non-cell-adhesive surface of the printed construct to cell-adhesive surface for culturing cells on it through a subsequent cross-linking of gelatin possessing Ph moieties. These results demonstrate the possibility of utilizing the presented cross-linking method for 3D bioprinting.