Fabrication of vascular-like structures using in situ cross-linkable hydrogel
based on gelatin, hyaluronic acid and carboxymethylcellulose
Functional vascular networks are fundamental for the fabrication of 3-dimensional thick tissues and organs for regenerative medicine. In this study, we combined crosslinkable hydrogel and electrochemical detachment of cells for rapidly engineering vascular-like structures. The crosslinkable hydrogel was composed of hydrazide-modified gelatin (gelatin-ADH) and aldehyde-modified hyaluronic acid (HA-CHO). The gelation occurred in less than 30 s after mixing these two components. We demonstrated that cells adhering to a gold surface covered with an oligopeptide layer could be transferred to the hydrogel by applying a negative electrical potential, which desorbs the oligopeptide layer from the gold surface. To apply this approach in the fabrication of vascular-like structures, we used a gold-coated cylindrical rod. On applying an electrical potential and extracting the surface layer of the rod, endothelial cells were transferred from the rod to the internal surface of the microchannel in the hydrogel. This technique can be a promising approach for fabricating vascularized 3-dimensional tissues.