Tattoos, once a hidden art, have undergone a surprising transformation. They have left behind their ancestral mystery to become essential elements of body beauty, transcending mere passing fashion. Regardless of the motif or culture that drives them, tattoos have evolved into authentic works of art that are intertwined with our daily lives. And the fascinating thing is that today’s science has taken a step forward by generating nano tattoos that function as biosensors, further expanding their possibilities. 
Nano tattoos for biometric monitoring
Art can be part of a piece of technology, and that is what is happening with a new idea created by Turkish scientists. They generated a technique to make nano tattoos that communicate wirelessly. This process does not require implants or energy sources for its functions. Its creators named it BNTS (backscattering-based nanotattoo sensor), which in English means “backscattering-based nanotattoo sensor”.
The research was published in the Institute of Electrical Engineers’ specialized journal IEEE Electron Device Letters. The purpose of these tattoos is biometric monitoring and transmission to a device such as a smartphone.
The researchers used two types of ink, one black and one white. The black ink is composed of a conductive graphene hydrogel. The white one is made of zinc oxide and contains nanowires. The latter ink is placed on top of the first layer made with black ink. By means of hydrogel, both layers are bonded together and allow electrical conduction. The two layers are injected together, albeit by means of different needles.
The technology, according to its creators, is based on ambient backscatter. Its frequency is between 900 megahertz and 2.45 gigahertz. When the tattoo receives radio frequency signals, it establishes communication with the smartphone. Using these signals, the cell phone monitors the tattoo and processes the information it receives. In this way, the health status of the person can be known in real time.
Other tattoos that help to monitor health
However, this tattoo does not mark a milestone in monitoring our health status. There are already other tattoos designed especially for people with diabetes, which can constantly transmit blood glucose levels to a device. In addition, there is a tattoo that also uses graphene ink to monitor blood pressure in real time.
Tattoos thus become autonomous devices capable of generating their own electrical signals. They generate their own energy through pressure changes, in the case of this latest study, thanks to the movement produced in the skin that is deformed when the tattoo is made.
At present, there are many scientists trying to develop new biosensors to monitor health. The important thing is to achieve, as in the case of tattoos, a low cost and that the device does not become a burden. With aesthetics in mind, nano tattoos are an excellent option.
