Figure 5.

(a) Extrusion bioprinting nozzle (or syringe) systems (pneumatic, piston and screw). (b) A digital computer-aided design (CAD) model with an outlook and an internal branched network of the vascular networks. (c) A common layer interface (CLI) file. (d) Schematic illustration of the fabrication process of a layered vessel model using a dual-jet extrusion printer by Wang et al. (e) A 3D printed hybrid hierarchical polyurethane-cell/hydrogel structure. (f) The middle part of (e) with branched/grid internal cell/hydrogel channels. (b–f) are adapted with permission from Ref. [49]. Copyright © 2023 Elsevier B.V. All rights reserved.