This is not a wearable device that requires charging, but a real, normal smart intradermal tattoo. Just like the ones we will see by the millions on beaches around the world.
A German research team developed a method for obtaining an intelligent tattoo without any use of electronics. A tattoo that can change color as a response to changes in the body's glucose, albumin or PH levels.
Real-time analysis and monitoring
The project is being tested on animals (pigs, to be precise). On their skin these special designs showed the variations of these biomarkers with legible gradations.
After mini dialysis this is another exciting step in the direction of real tattoos that without any energy consumption allow patients and doctors to monitor chronic ailments such as diabetes or those affecting the kidneys at a glance.
The research
The team led by the chemical engineer Ali Yetisen from the Technical University of Munich was able to create truly transformative technology. A modern method based on a decoration practice that humans have practiced since the dawn of time.
“Changing the appearance of the body by injecting pigments into the dermis layer is a practice that is more than 4000 years old,” writes the researcher in his paper. “We have developed cosmetic technology to combine artistic tattoos and colorimetric biosensors. The result is that the smart tattoo works as a diagnostic display by changing color in response to changes in the body."
The choice fell on these three biomarkers (glucose, albumin, ph) because often their variation indicates that something is quickly going wrong in our body.
Albumin it is a protein in plasma whose level is low when there are kidney or liver problems, and it is high when there are heart problems. The glucose needs to be continuously monitored by patients with diabetes, because they have problems with the body's ability to metabolize sugars. The variations of PHon the other hand (acidosis when low, alkalosis when high) are a general indicator. They indicate a wide range of problems that need further analysis.
The team created several dyes that can detect these changes in the interstitial fluid, which also transports oxygen and glucose between cells and is found almost everywhere in our bodies. The albumin sensor is yellow in color and turns green as levels increase. The glucose sensor uses the enzymatic reactions of oxidase and peroxidase: the change in its values determines the transition from yellow to dark green. For PH there is a range that goes from yellow to blue when the levels are in the range between 5 and 9 (the 'normal' human one is around 7,4).
Reading this study I learned something new for me: pig skin was not only used by the German team for the tests, but it is also the "exercise book" for tattoo artists.
The next steps
Human tests will be needed to confirm and improve characteristics and performance. Just to say, currently two of these three colors are not reversible. In other words, in two out of three cases, once the color has been changed it doesn't go back, only the one on the PH is already perfected. In the next tests, synthetic receptors will be added to the two shades yet to be perfected. In the immediate future, however, tests will continue on live animals to evaluate any adverse reactions.
By the time the human tests are carried out, which will plausibly take at least two more years, this smart tattoo will monitor so much more. Thing? For example also the levels of electrolytes, proteins, pathogenic microorganisms, gas and hydration.
Until the day we look at our forearm and know we're getting a cold. Or that we are entering into a sugar reserve, or that perhaps we need to drink more.
The research was published in the international edition of the journal Angewandte Chemie
