Researchers from the National University of Singapore (NUS) and the Agency for Science, Technology and Research (A*STAR) have created a wearable, stretchable sensor that enables non-invasive, continuous, and real-time solid-state epidermal biomarkers (SEBs) detection.

This sensor is expected to offer a convenient alternative to traditional methods that require biofluid samples.

It is developed by a team led by assistant professor Liu Yuxin from NUS and Dr Yang Le from A*STAR's Institute of Materials Research and Engineering (IMRE).

The sensor is hydrogel-based and can detect biomarkers such as cholesterol and lactate on the skin directly. This development is significant for early disease detection, chronic disease management, sports physiology and remote patient monitoring.

Yuxin said: “The ionic conductive hydrogel layer that solvates the biomarkers and the electronically conductive hydrogel layer facilitates electron transport.

“This bilayer enables the sequential solvation, diffusion and electrochemical reaction of the biomarkers. Another highlight is the sensor’s sensitivity with biomarkers being detected precisely even in low amounts.”

The wearable sensor overcomes the limitations of current biofluid-based methods by detecting SEBs, which are found in the skin's outermost layer and are indicative of various health conditions.

Its hydrogel matrix allows for the diffusion and electrochemical reaction of these biomarkers, providing accurate health data wirelessly to an external interface.

Clinical studies have shown that the sensor's detection of biomarkers on the skin correlates strongly with blood sample analyses, validating its accuracy.

The NUS and A*STAR team is working to improve the sensor's longevity and sensitivity, as well as expand its capabilities to detect more biomarkers.

Collaborations with hospitals are underway to further validate the technology and explore its use in continuous glucose monitoring and assessing dynamic resilience in patients.

Yang Le said: “This wearable sensor is the first in the world that can monitor biomarkers on dry or non-sweaty skin. The sensor’s novel bilayer hydrogel electrode interacts with and detects biomarkers on our skin, allowing them to become a new class of health indicators.”