Future ink: Biosensory tattoos as diagnostic aids

Sensory tattoos are suited for more precise diagnostics due to their proximity to interstitial fluids where biomarkers are measured. Initial studies with pig skins give hope.

Glucose monitoring with tattoos

Why do we use continuous monitoring?

For a long time, medicine was more focussed on the treatment of acute illnesses. This still applies in many parts of the world, but in recent decades, Western medicine has shifted into the constant surveillance of heath indicators. In that context, the continuous monitoring of biomarkers has become a focal point. For example, the continuous measurement of blood glucose levels plays an important role in the treatment of diabetes.

More options for continuous monitoring are being researched. However, these are often expensive and not accurate enough. But tattoos with special inks could provide new options for tracking different health conditions.

What are the advantages of biosensory tattoos?

Parameters such as glucose or protein are measured in the interstitial fluid. This is also found in the skin. Due to their proximity to the interstitial fluid space, tattoos are particularly suitable for monitoring certain biomarkers. They also have a long shelf life and are relatively easy to apply. They are also generally easy to analyse - either with the naked eye or with a smartphone.

How do biosensory tattoos work?

Biosensory tattoos work using a special ink that is applied to the skin in the same way as a normal tattoo. This ink can then indicate changes in the pH value, blood glucose or albumin level, for example, by changing colour.

A similar principle is based on fluorescent particles that can be visualised using an LED lamp and a mobile phone.

Both concepts have already been tested on pig skins. For example, it was possible to diagnose a fluctuation in blood sugar levels within 30 seconds by the changing colour of a tattoo. The technology has not yet been applied to humans, but research results are promising.

Conclusion for medical practice

Tattoos as sensors for biomarkers appear to be a promising option. Convincing results have already been achieved in tests with animal skins. There are still a few hurdles to overcome before it can be used in humans, such as identifying and managing possible cutaneous intolerances. However, this diagnostic tool could improve medical care in many parts of the world, because it is cost-effective, and easy to use.

Source
  1. Dhond, K., Hu, Y. & Yetisen, A.K. Dermal tattoo biosensors. Dermatologie 74, 819–821 (2023). https://doi.org/10.1007/s00105-023-05195-6