Researchers have produced a programmable microbial ink capable of spontaneously assembling complex predetermined structures. A concept full of promises in lots of disciplines.
We no longer present 3D printing, which has now become democratized at a maddening speed. From heavy industry to nanotechnology through medicine, construction and entertainment, it has ended up inviting itself into many aspects of our life. But a team of Harvard researchers has just taken the concept to a level never before reached, with a kind of “programmable 3D ink”.
If this description is particularly obscure, it is because it is also the case of this technology which does not really present an equivalent today. It is a liquid and opaque substance (hence its nickname “ink”) which would be both a kind of 3D printer, but also its own substrate. A concept that seems far-fetched. And it would indeed be if this compound did not have a phenomenal resource: life!
Because the most important component of this substance is Escherichia coli. It is a small bacterium that occurs naturally in the human body; beneath her insignificant airs, she is one of the undisputed superstars of biology. In addition to having been at the center of many major discoveries in fundamental biology, it is a model organism which has served as a support for countless remarkable experiments, particularly in genetics. It is also a formidable experimental platform that has opened the door to spectacular bioengineering experiments.
And this is still the case in these works. With a good dose of manipulation, the researchers were able to produce a substance based on microbial cells programmed to “produce a network of nanofibers that assemble spontaneously”. A description that seems straight out of science fiction.
But unlike these fictitious compounds, this “ink” is all that is more real, and could even prove very useful. When they identified its properties, they placed it in a 3D printer and were able to produce heaps of variants of biomaterials with various and varied functions.
For example, they imagined biostructures capable of producing certain active ingredients; this allowed them to imprint a structure producing azurin, a protein known for its anticarcinogenic properties. The researchers also suggest that this network of nanofibers could make it possible to capture toxic compounds; a concept already successfully tested on Bisphenol-A, recognized as an endocrine disruptor.
The idea of printing biological material is not new. Science has been exploring this avenue for some time, particularly in regenerative medicine; Ultimately, it could allow the production of bespoke spare organs, cultured from the recipient’s genetic material to eliminate any risk of rejection. But the technology presented in this work goes even further.
To produce an organ, the theory is that we start with stem cells that we reprogram at the genetic level so that they differentiate into a particular type of cell (liver cells, for example). So it comes down to saying to these clusters of cells “You will be a kidney”,“You will be a liver ”, And so on. Once their vocation is thus determined, there is no turning back (or almost not, to be exact). But this “ink” imagined by the Harvard researchers pushes the concept much further.
The basis of the biomaterials of the future?
This is what makes these two proofs of concept so interesting; these are the foundations on which we can hope to build new drug delivery systems, production of substances, treatment and chemical filtration … On paper, this technology is so versatile that researchers will have to compete in imagination to exploit its full potential.
Most impressive, however, is that the modified E. coli present in the ink would still be able to reproduce and regulate their own cell growth. We can then imagine producing revolutionary compounds such as self-repairing materials; enough to greatly simplify the logistics chain in very remote places, and even on other planets. Let’s just hope that no mad scientist with varying ethics will notice the disturbing resemblance to a certain symbiote from the Marvel Universe or to the terrible Protomolecule of The Expanse …