Scientists from MIT have developed live tattoos that can respond to different stimulants using genetically modified bacteria. With electronic tattoos and intelligent ink technologies, it shows how wearable sensor technology carries an exciting potential. While engineers work with dissimilar materials, living cells must be a very interesting use. As a first step, we needed to find bacteria with cell walls that were strong enough not to die from the head of the 3D printer. Also, the bacteria had to be compatible with the hydrogels used in the 3D printer. It can be reduced to a resolution of 30 microns thanks to the technology developed afterwards. To make a patch from the 3D printed bacterial cells, bacteria were placed on top of an elastomer layer, such as branches of a same tree. Each branch of bacteria is designed to respond to a different chemical stimulus. For example, the bacteria that are applied to the human hand change color by showing different responses to different chemicals. This patch or tattoo is actually quite like science fiction. On this side, genetically modified bacteria work like transistors that communicate with each other. In the future, it is planned to create platforms that can live wearable wearable platforms. Recently, by using this technology, warning sticks can be made and technologies can be developed to monitor wearable health monitors by generating signals to the pH, temperature variables occurring in the body.
