Bacteria are an important part of the world we live in. They can be dangerous or beneficial, and they’re present in huge numbers all around us. Bacteria have a variety of applications, and one unusual one which was recently developed by MIT is the idea of Living Ink.

Living Ink
Image source: YouTube Video Screenshot

Behind the Living Ink

This new technology was recently successfully created by a team of engineers working at MIT. The 3D-printed living ink can react to specific chemicals it comes into contact with by illuminating itself. Genetic engineering is the mechanism where by these engineers were able to create living and responsive cells in an ink form.

According to MIT News, the engineers used a water/polymer mix, nutrients, and living cells to form an ink that can formed into 3D structures using a 3D printer. The reason bacteria was chosen over other cells was because of its resilience in stressing situations. The fact that the bacteria could survive when added to a hydrogel, and then later coping with the intense force of being pushed through a small print nozzle, suggests that these cells were definitely the right choice for the first form of viable living ink.

As far as the conditions to which the cells react go, the living ink can be pre-programmed to respond to a wide range of different chemicals. Said reaction has a visible effect by as the cells light up. As a test and demonstration, the MIT engineers printed a thin “tree” of sorts, with each branch reacting to a different chemical.

Then, like a tattoo, the finished hydrogel patch was placed on the back of a hand that had been covered in the reactive chemicals. The image below shows the outcome, with the living ink responding to the different chemicals through visual feedback.

Significance and Future Study

This breakthrough in living ink technology builds a future in which tattoos are able to monitor for different chemicals when worn.

The MIT researchers have stated that with further development, it may be possible to have the cells communicate with each other. This would allow for a basic 3D-printed wearable computer that’s responsive and alive. For now, however, the focus with this technology is to form living sensors that we can wear as patches.

The practical applications of this living ink in its current form is to use it as a way to easily deliver drugs over time, or even to revolutionize the field of surgical implants.

While this technology is still in its infancy, the implications of a living ink are immense. The ability to engineer bacteria and have them survive through a process as stressful as 3D printing opens the door to all sorts of future tech development.

While at this current moment the ink simply responds to different chemicals, the fact that it’s the base for a living computer of sorts means this complexity and applications of this technology will only continue to grow. We’ll have to see what the future of living ink has in store.