In vivo bioprinting, a direct fabrication technique for creating artificial tissues and medical devices on target sites within the body, is limited by its applications near the skin or the need for open surgery for internal organs. This paper reports a ferromagnetic soft catheter robot (FSCR) system for in situ computer-controlled bioprinting via magnetic actuation. The FSCR, designed by dispersing ferromagnetic particles in a fiber-reinforced polymer matrix, enables stable ink extrusion and printing of various materials. A superimposed magnetic field allows for digitally controlled printing. The authors demonstrate printing on planar and curved surfaces, including minimally invasive in vivo bioprinting of hydrogels in a rat model, showcasing the potential for intelligent and minimally invasive biofabrication.
