Researchers from the Center for Nanoparticle Research at the Institute for Basic Science have developed a sweat-based glucose monitoring and maintenance device. The team’s work was published this week in Science Advances.
The sweat-based system rapidly measures glucose using small sensors and delivers a precise, controlled dosage of drug according to the device’s measurements, the team reported.
The research group sped up sweat collection by designing the system to function using a small amount of sweat. The team used electrochemically active and porous metal electrodes to make the system more sensitive and more reliable. The device also features more sensors of a smaller size, delivering a more reliable sweat analysis than previous iterations.
“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,” first author Lee Hyunjae said in prepared remarks.
The patch-based device is composed of an extra sweat uptake layer and a waterproof band to efficiently absorb the user’s sweat while keeping the patch intact.
The researchers said they were also able to load drugs for feedback therapy on 2 different temperature-responsive phase change nanoparticles. The nanoparticles were embedded in microneedles that were also coated with phase change materials.
When the system detects an elevated glucose level, the integrated heater activates 1 or both phase change nanoparticles, depending on the temperature.
“The previous systems cannot prevent natural diffusion of the drugs from drug reservoir, and rely heavily upon elevation of temperature to enhance the rate of drug diffusion. Our system uses PCMs to prevent drug release by using the melting properties of phase change materials above critical temperature, enabling stepwise drug delivery,” Lee said. “Furthermore, different drugs can also be loaded in phase change nanoparticles for stepwise and multiple drug delivery.”
The researchers also evaluated a disposable, sweat-based strip sensor and compared to it their patch system.
“This convenient and accurate system is also compatible for mass-production as it uses the metal electrode that can be easily fabricated via a conventional semiconductor fabrication process,” Lee said. “Although there is still room for improvement before applying our system into the clinical application, this approach can surely contribute to improve the quality of life of diabetic patient by managing blood glucose more easily,”
“The fundamental mechanism underlying this system can be applied in the diagnosis and clinical treatments of various diseases not to mention diabetes,” corresponding author Kim Dae-Hyeong added.