3D Printer printing “droplet networks” that function as artificial human tissue. From the Smithsonian Blog:

Today, a new study suggests 3D-printed material could one day mimic the behavior of cells in human tissue. Graduate student Gabriel Villar and his colleagues at the University of Oxford developed tiny solids that behave as biological tissue would. The delicate material physically resembles brain and fat tissue, and has the consistency of soft rubber.

To create this material, a specially designed 3D printing machine followed a computer programmed diagram and ejected tens of thousands of individual droplets according to a specified three-dimensional network. As seen in the video above, its nozzles moved in various angles to establish the position of each tiny bead. Each droplet weighs in at about one picoliter—that’s one trillionth of a liter—a unit used to measure the size of droplets of inkjet printers, whose nozzle technology works much the same way to consolidate tiny dots of liquid into complete images and words on paper.

The droplets of liquid contained biochemicals found in tissue cells. Coated in lipids—fats and oils—the tiny aqueous compartments stuck together, forming a cohesive and self-supporting shape, with each bead partitioned by a thin, single membrane similar to the lipid bilayers that protect our cells.

Several 3D-printed droplet networks. Image courtesy of Gabriel Villar, Alexander D. Graham and Hagan Bayley (University of Oxford)
The shapes that the printed droplets formed remained stable for several weeks. If researchers shook the material slightly, droplets could become displaced, but only temporarily. The engineered tissue quickly sprung back into its original shape, a level of elasticity the researchers say is comparable to soft tissue cells in humans. The intricate latticework of a network’s lipid bilayers appeared to hold the “cells” together.

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