Ali Khademhosseini of the University of California, Los Angeles led a study describing a new three-dimensional (3D) printing method to construct therapeutic biomaterials from multiple materials. His team employed stereolithography in conjunction with a customized 3D printer Khademhosseini designed, which uses a custom-built microfluidic chip with inlets that each produce a distinct material, combined with a digital micromirror array. The team used varying hydrogels that cohere into scaffolds for tissue, while the micromirrors steered light onto the printing surface to mark the outline of the object. Illumination also catalyzed the formation of molecular bonds in the materials, inducing hydrogel solidification. The mirror array re-directed the light pattern during printing to indicate the contours of each new layer. The process was initially used to produce simple shapes, and then applied to complex 3D structures to emulate muscle tissue and muscle-skeleton connective tissues.
More info here: UCLA Samueli Newsroom