A stereolithography-based bioprinting platform for building therapeutic biomaterials from multiple materials could help advance on-demand printing of artificial tissues for regenerative medicine. The platform uses a specially adapted 3D printer that has a custom-built microfluidic chip with multiple inlets. Each inlet prints a different material. The printer also has a digital micromirror device that directs light onto the printing surface, illuminating the outline of the object that is being printed.
During the 3D printing process, the micromirror adjusts the light pattern to direct the shape of each new layer of the object. The patterning by the digital micromirror device is synchronized by a moving stage and the microfluidic device, which contains four on/off pneumatic valves. The microfluidic device is capable of fast switching between different (cell-loaded) hydrogel bioinks to achieve layer-by-layer multimaterial bioprinting.