One of the most common factors that prevents people with diabetes from routinely monitoring their blood sugar levels is that most modern machines require needles and small amounts of blood. However, researchers at Pennsylvania State University have developed a new glucose monitoring system that needs no needles to obtain accurate readings. The new wearable device promises a less intrusive glucose monitoring system that could become the normal way people suffering from diabetes monitor glucose.
The device is made using laser-induced graphene (LIG), a material made from carbon layers that are only one atom thick. The material has a high level of electrical conductivity and can be fabricated in seconds. Researchers believe LIG is an ideal framework for a sensing device, but they had to overcome a significant problem with using the material for monitoring glucose levels.
That significant challenge was that LIG is not sensitive to glucose. That problem required researchers to deposit a glucose-sensitive material onto the LIG. The glucose-sensitive material the team chose was nickel, which is described as having a robust sensitivity to glucose. The nickel was combined with gold to lower the risks of an allergic reaction.
Researchers believed LIG combined with a nickel-gold alloy would detect glucose in low concentrations from sweat on the skin’s surface. To detect glucose levels in sweat, the sensor had to have high glucose sensitivity. Concentrations of glucose in sweat are around 100 times less than in the blood, but glucose levels in sweat and blood have a strong correlation.
The sensor researchers constructed was sensitive enough to glucose to allow the team to eliminate enzymes typically used to measure glucose in more invasive tests. A microfluidic chamber was also attached to the sensor that was smaller than previous configurations and promoted wearability to provide the alkaline solution required for non-enzymatic sensors. The result was a device approximately the size of a quarter that’s flexible enough to attach securely to the body.