Sep 08, 2025

The nano sweat patch that could replace blood tests

A research team developed a wearable sweat patch that tracks health markers in real time, opening possibilities for easier disease monitoring.

(Nanowerk News) A new wearable patch could one day replace certain blood tests with a quick check of sweat. A research team at KAIST has created a flexible sensor that attaches to the skin and continuously tracks changes in the body by analyzing sweat in real time (Nature Communications, "All-flexible chronoepifluidic nanoplasmonic patch for label-free metabolite profiling in sweat").

The device, developed by Professor Ki-Hun Jeong and his team in the Department of Bio and Brain Engineering, overcomes a long-standing challenge in sweat-based health monitoring. Traditional methods struggled to collect sweat efficiently or required fluorescent tags to detect specific molecules. The new patch does both collection and analysis without added labels, making the process simpler and more precise.

Flexible microfluidic nanoplasmonic patch (left). Sequential sample collection using the patch (center) and label-free metabolite profiling (right). In this study, we designed and fabricated a fully flexible nanoplasmonic microfluidic patch for label-free sweat analysis and performed SERS signal measurement and analysis directly from human sweat. Through this, we propose a platform capable of precisely identifying physiological changes induced by physical activity and dietary conditions. (Image: KAIST) (click on image to enlarge)

The technology combines two advanced fields: nanoplasmonics, which uses nanoscale patterns of metal to detect molecules with light, and microfluidics, which guides sweat through hair-thin channels. As sweat moves through the patch, it fills a series of chambers, allowing researchers to track how its chemical makeup changes over time.

In human trials, the patch monitored three key metabolites—uric acid, lactic acid, and tyrosine—while participants exercised. Using artificial intelligence, the system could pick out these substances even within sweat’s complex mix. This marks the first time a wearable has successfully measured multiple metabolites simultaneously without labels.

Jeong said the work opens the door to noninvasive, continuous health monitoring. In the future, the patch could be used not only for managing chronic diseases but also for tracking how patients respond to medications, monitoring environmental exposures, and identifying new biomarkers linked to metabolic conditions.

Source: Korea Advanced Institute of Science and Technology (Note: Content may be edited for style and length)