Figure 2.

Minimally invasive internal in situ bioprinting. (A) Natural orifice transluminal endoscopic bioprinting strategy. Schematic representation (i) and practical model (ii) of in situ bioprinting for treatment of gastric wall injuries. The endoscopic robot could finely print multiple layers of cell-laden bioinks with high resolution (iii). (B) Laparoscopic bioprinting using a ferromagnetic soft nozzle. The bioprinting strategy was based on the insertion of the nozzle through a small incision, and its deformation in a programmable magnetic field while extruding the bioink to form the printing structure (i). The ferromagnetic nozzle was formed from a polymeric shell embedded with magnetic particles and reinforcing fibers (ii). Minimally invasive in situ printing on the liver of a living rat (iii-v). The process was consisted of CT scanning to reconstruct the liver surface (iii), definition the printing path on the upper liver surface (iii), and in situ printing (iv, v). The setup is shown in (iv) while a close-up view of the printing construct is shown in (v). Reproduced with permission from IOP Publishing [23] (A) and Nature Publishing Group [25] (B).