Signs of good health will show on your skin in future, literally. Scientists in Germany have taken
a step in this direction by tapping into the ancient art form of tattoos. They have developed specialised dermal tattoo biosensors, which use the interstitial fluid or the fluid found in the spaces around cells to study alterations in bodily conditions. What this means is that you will be able to determine parameters such as pH levels, blood glucose, uric acid, albumin concentrations, allergens, hydration levels and electrolyte balance at a glimpse. Think of it as your personal, portable health monitoring device that offers minimally invasive, timely and blood-free readings of important biomarkers.
For now, the experiments have been conducted on pig skin, but the promise this technology holds
for humans is being considered the next frontier of at-home diagnosis.
The genesis
It began with chemical engineer Ali Yetisen, along with his team of researchers from the Technical University of Munich, Germany, creating a functional colour-changing intradermal tattoo in 2019. A traditional tattoo gun was used to inject the colourimetric dye into the skin. Once it reached the interstitial fluid, three biomarkers were studied: pH changes that signal kidney and lung problems, glucose levels for diabetics and albumin levels to identify kidney, liver and heart issues. The role of interstitial fluid is significant in that it transports metabolites (a substance made or used when the body breaks down food) between capillaries and cells. The levels of concentration of the changing colour help determine the intensity of the disease.
“Medical tattoos are being considered the beacon of hope for those suffering allergies as well, as they help evaluate the precise levels of allergens in the body and how active,” says Delhi-based nephrologist Dr Gurpreet Rana. “The medical community is hopeful that intradermal tattoos will provide accurate disease progression analysis for those suffering from alkalosis, hyperglycemia, metabolic acidosis and hypoalbuminemia in the future,” he adds.
The advantages
One of the greatest benefits of tattoo technology is the early detection of diseases. “It also has an edge over the readily available wearable medical devices, which, despite being sophisticated, require care and maintenance. Some wearable devices also increase the risk of Allergic Contact Dermatitis (ACD) and other skin disorders,” says Gurugram-based dermatologist Anjali Dhawan.
The best part about the tattoos? Just because they have a medical purpose, they don’t have to be boring. You can choose any design, provided it’s not too intricate, as it may obstruct the reading, which must be visible for monitoring.
The flip side
Toxicity or ink allergy is a huge worry pertaining to colour-changing tattoos, but researchers are working on designing biosensing inks that have been proven to be safe for medical use. The other limitation is the irreversibility of pigments in certain types of detections. This hurts signal detection and hinders long-term monitoring. The albumin and glucose tattoos can only change once, which means once altered, you're stuck with it, sans any medical function. Having said that, scientists are making progress by using synthetic receptors that will mimic the role of natural ones. Not just that, the scope of medical tattoos is being broadened exponentially to include monitoring of hydration and electrolytes in the body. Ready to get inked?
Designs for future
Research is underway with regard to whether smartphone apps would be able to read the changing tattoo colours and estimate parameters.
Not just the usual pH levels, blood glucose, uric acid and albumin concentrations, medical tattoos will also be able to record variations in metabolism too.
Researchers and scientists aim to make these tattoos as low-cost as possible, so they can benefit
millions of people.