A Smart Tattoo That Could Save Your Life

WRITTEN BY: Tara Fernandes

Color-changing tattoos, powered by nanotechnology, that sense imbalances in your biochemistry providing a visual signal on your skin to seek medical help. Science or science fiction? If recent progress made by biomedical scientists and engineers is anything to go by, such technology may not be quite as futuristic as it sounds.

Dynamic tattoos have been in development for years, with early prototypes being able to successfully pick up changes in sodium, glucose, electrolytes or pH levels in animal models. Among the most intriguing developments was a cancer-detecting tattoo consisting of engineered skin cells reported in 2018. Blood calcium levels are typically elevated in many types of cancer. Here, the implantable sensor consists of calcium-sensing cells that produce melanin (the natural skin pigment) in response to rising blood calcium levels, thus creating a visible color change on the surface of the skin.

If permanent tattoos are too much commitment, scientists have a solution for that too. Temporary electronic tattoos designed to measure electrophysiological signals such as brain activity or hydration levels are also in the works. Called “epidermal electronics”, these battery-powered tattoos are comfortable to wear and could even wirelessly connected to your devices.

A recent publication in ACS Nano has revealed yet another application for tattooable nanotechnology. University of Colorado Boulder researchers, led by emergent nanomaterial specialist Carson Bruns, spearheaded the creation of a new innovation: solar freckles. These invisible ink tattoos turn blue only in the presence of ultraviolet radiation (a major risk factor for skin cancer development). This color-changing nanosensor is implanted into the skin using traditional tattoo machines and provides the user with a visual cue to slap on more sunscreen to avoid skin damage. Ultimately, the researchers are optimistic that similar technologies can be applied to a broad range of preventative and diagnostic clinical applications.