피 안 뽑고 땀 한 방울로… 고려대, 체내 약물 추적하는 ‘AI 피부 패치’ 개발

A new "AI sweat patch" technology developed by researchers at Korea University is able to precisely track the concentration and breakdown time of drugs in the body using only a thin patch on the skin. This technology has the potential to be applied in various fields such as personalized medication management and doping tests for athletes.

The sensor, developed by Professors Kim Dong-won and Yoo Woo-sang from the Bio-Car Engineering Department, was published online in September 10th in the prestigious journal "International Journal of Extreme Manufacturing". The researchers tested the patch on 10 adults by giving them 135mg of caffeine and having them run on a treadmill at 8km/h.

After every 30 minutes, they replaced the patch on their forearm to analyze the metabolites in their sweat. The results showed that the breakdown of caffeine into para-aminotriazole, a byproduct, varied significantly from person to person, demonstrating individual differences in the activity of enzymes that break down caffeine. The patch's challenge lies in the analysis of sweat, which contains many waste products along with the metabolites.

To tackle this issue, the researchers used two methods. Firstly, a "gold nanogel" filter on the patch selectively absorbs small molecules (mass 480-580g/mol) from sweat, filtering out larger proteins that would otherwise contaminate the sensor. The gold nanoparticles amplify the signal of the drug by 100,000 times. The patch maintained its performance even after being bent or twisted 200 times, and showed no immune reaction or inflammation after being attached to rabbit skin for three days.

Secondly, an AI algorithm calculates the drug concentration with high precision by analyzing complex signals in sweat and quantifying the concentration of each substance. It also takes into account factors such as the amount of sweat released and evaporation, reducing the impact of these factors and providing a more accurate calculation of drug levels and breakdown times in the body.

Professor Kim Dong-won said that it's possible to measure drug levels in the body precisely on the skin without the pain of blood extraction, and that this technology could be widely used for personalized treatment and managing exercise fatigue. Professor Yoo Woo-sang noted that the system could maintain stable signals even with changes in body movement or sweat secretion, making it highly suitable for developing portable testing equipment for detecting illegal doping substances or drug use in athletes.

The researchers plan to develop this technology into IoT-connected health management devices and on-site doping and drug testing systems.