Well, whaddya know? It seems that E. coli, the bane of Romaine and spinach everywhere, has at least one practical use. Researchers at Harvard have created a kind of 3D-printable ink that is alive and made entirely of microbes produced by E. coli. Although this is not the first so-called living ink, it does hold the title of the first living ink that doesn’t need any additional polymers to provide structure.
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Because the ink is alive, it is technically programmable in the sense that it can self-assemble proteins into nanofibers, and further assemble those into nanofiber networks that comprise hydrogels.
One of the researchers compared the ink to a seed, which has everything it needs to eventually grow into a glorious tree. In this way, the ink could be used as a renewable building material both on Earth and in space. Though the ink does not continue to grow after being printed, the resulting structure would be a living system that could theoretically heal itself.
The ink creation process begins when the researchers induce genetically-engineered bacteria cultures to grow the ink, which is also made of living cells. The ink is then harvested and becomes gelatin-like, holding its shape well enough to go through a 3D printer. It even passes the bridging test, supporting its own weight between pillars placed up to 16 mm apart. (We’d like to see a Benchie.)
Continue reading “It’s Printable, It’s Programmable, It’s E. Coli”