Student work: Dermal Abyss: the New Generation of Tattoos

Blog post on an innovation

by Sara Paciaroni, fourth year student in 2017-2018

Today, around 20 million people in Britain have at least one tattoo and the number of tattoos carried out every year is on the rise. But what if tattoos could be beneficial to our health? What if tattoo artistry combined with biomedical engineering could transform body art in wearable displays revealing information inside the body?

This is what researches at MIT and Harvard Medical School, led by Katia Vega, successfully demonstrated last September. Their Dermal Abyss project consisted of developing a special ink containing biosensors, which, patterned into the skin, encode information from the interstitial fluid producing colour changes. Too technical?

Okay, let’s try again: The interstitial fluid present in our skin can be considered a “surrogate” of the substances contained in your blood. This ink contains molecules called “biosensors” that are particularly sensitive to certain substances. When levels in these substances, called “biomarkers”, rise or decrease, the biosensors, which are colorimetric and fluorescent, produce a response visible on the skin. Yes, you read that right, this tattoo changes colour in response to changes in your body. (Watch the interview with Dr Julien Reboud from the University of Glasgow for an expert’s explanation!)

The appearance of our skin already reveals something about what is happening in our body: it can indicate the presence of diseases, lack of nutrients or our emotions. Dermal Abyss exploits this property and takes it even further revealing information that would be otherwise impossible to determine without a blood test or the use of possibly invasive devices that require batteries or periodical maintenance.

This breakthrough innovation could not only revolutionise the concept of body art but also the sector of wearable devices employed to monitor certain conditions. The idea of devices implanted to modify the human body is not new, nor is the one around tattoos as medical alerts.

The peculiarity of the smart ink is that it merges the biosensors directly with the skin turning it into a display with no visible devices. “We wanted to go beyond what is available through wearables today” postdoctoral fellow Ali Yetisen told the Harvard Gazette . “And so we came up with the idea that we could incorporate biosensors in the skin.”

Thanks to the smart tattoo, diabetics could say goodbye to piercing their fingers every few hours. The amount of glucose in the dermis (where the ink penetrates) is in fact close enough to the level in your blood, so that the biosensors can detect its changes, turning from green (low level of glucose) to brown (high level of glucose) and vice versa.

The tattoo could be useful for athletes too. While our body signals dehydration through thirst mechanisms, Dermal Abyss could be useful to monitor dehydration on the long term, which could eventually lead to kidney failure. In this case, dehydration would be signaled by the tattoo turning a fluorescent green.

It has also been demonstrated that pH balance can be an indicator of local or systemic pathologies like diabetic ketoacidosis, a life-threatening complication of diabetes that causes harmful substances to build up in the body. In this case, the biosensors would be able to detect these early on by revealing changes in pH turning either a dark purple (acidic pH) or a bright pink (alkaline pH).

Contrary to popular belief, tattoos have always been a thing. Marking your skin with an infinity symbol for your 18th birthday or getting your children’s dates of birth in Roman numerals might seem like the latest trend, but this practice has actually been around for centuries. From brides across Asia tattooing their hands, to indigenous Australian body art as signs of social interaction, to African designs involved in religious rites; tattoos have always been part of human history, playing different roles in cultures around the globe.

Tattoos, though, are a relatively new phenomenon in Western societies. They were a prerogative of the European upper class in late 19th century and shifted to the working class at the beginning of the 20th with big anchors needled in in sailors’ arms and became one of the emblems of rebellious movements in the 60s. Even if subjected to prejudices, tattoos entered mainstream culture in 2000s.

Although some argue that we are past a “peak tattoo” and that the trend is now facing an inevitable drop, the development of technologies like Dermal Abyss, which aim at merging the human body with devices, may contribute to a revaluation of tattoos and body modification as covering a specific role in society.

Unfortunately, you cannot get the tattoo yet as “there are currently no plans to commercialise Dermal Abyss as a product”, said Yetisen. “We wanted to demonstrate an idea. Companies would be better positioned to create a product for the market, but it will be definitely commercialised in the future. When the time comes, the tattoo could be obtained at certified tattoo shops or local clinics and it will certainly benefit a lot of people.”