Featuring small and sensitive sensors, the sweat-based system enables rapid glucose measurement, helping to provide a multistep and precisely controlled dosage of drug.

Earlier, the researchers presented a study on the wearable graphene-based patch that enables diabetes monitoring and feedback therapy by using human sweat.

The sweat-based monitoring, which is an alternative approach, is said to provide a painless blood glucose monitoring method for better control of blood glucose levels.

To enhance the sweat collection, the researchers redeveloped the system to function under a small amount of sweat.

Researchers have used electrochemically active and porous metal electrodes to speed up the sensitivity of the system.

The miniaturized sensor design of the device enables sweat analysis even with 1µl of sweat.

The first author of the study Dr. LEE Hyunjae said: "It was quite a challenge to find the optimal size of the sensors. If the size is too small, the signal becomes too small or the surface functionalization becomes difficult to handle.”

For precise reading and feedback therapy, the patch system integrates an additional sweat uptake layer that includes soluble and porous carbohydrate network, as well as waterproof band to facilitate the sweat collection.

In addition, the system allows precise and timely drug delivery.

Drugs for the feedback therapy will be loaded on two different temperature-responsive phase change nanoparticles (PCNs), which are implanted in the microneedles that additionally coated with phase change materials (PCMs).

The integrated heater modulates thermal actuation to activate either PCN1 alone or both PCNs, once the system detects a high glucose level.

Controlled by three multichannel heaters, the thermos-responsive microneedles can deliver the drug up to six steps of drug dosages in response to the measured sweat glucose level.

The researchers reported that the blood glucose level has been suppressed significantly when the more drug is delivered to the diabetic mice.

Image: Researchers from the Institute for Basic Science have designed sweat-based glucose monitoring and maintenance device. Photo: courtesy of Institute for Basic Science.