Researchers at the Korea Institute of Science and Technology have developed a wireless device that monitors glucose, lactate, and pH levels.
Electronics engineers have recently developed wearable and implantable devices using organic electrochemical transistors (OECTs) to detect and amplify biological signals. These flexible devices track physiological processes like heart rate and sleep patterns, which are valuable in sports and healthcare. They also monitor health indicators such as glucose and cortisol levels, which are crucial for medical diagnostics. However, integrating wireless communication circuits to transmit data often requires inorganic materials, which can compromise the device’s flexibility and size.
Researchers at the Korea Institute of Science and Technology (KIST) have recently developed an innovative wireless device capable of monitoring multiple biomarkers, such as glucose, lactate, and pH levels. The device combines components made from both organic and inorganic materials, offering high performance and exceptional mechanical stability, with an overall thickness of just 4 μm.
The device features organic electrochemical transistor (OECT) biochemical sensors paired with inorganic micro-light-emitting diodes (μLEDs). To create the OECT sensors, the team patterned gold electrodes and a polymer blend of two ionomers onto an ultrathin parylene substrate.
These sensors are connected to μLEDs constructed from inorganic materials. The OECTs can detect specific biomarkers because the current flowing through them varies with the concentration of these biomarkers in their environment. This variation in the OECT channel current subsequently controls the light output from the μLEDs, enabling the wearable device to monitor the biomarkers effectively.
In preliminary tests, the biomarker monitoring device, which is only 4 μm thick, showed promising results. It demonstrated a high transconductance (gm) of 15 mS and outstanding mechanical stability. The researchers also discovered that the device could analyze near-infrared images and predict glucose, lactate, and pH concentrations based on these images.
Looking ahead, there is potential for further testing and enhancements of the device, which could contribute significantly to advances in medical technology. Additionally, adaptations could be made to power the device using soft batteries or solar cells, leading to a fully chipless sensing system.
Reference: Kyung Yeun Kim et al, An ultrathin organic–inorganic integrated device for optical biomarker monitoring, Nature Electronics (2024). DOI: 10.1038/s41928-024-01237-6
