No More Diabetes Testing Using Blood? New Glucose Sensor
Imagine not having to prick your finger, arm, or thigh ever again to take a reading of your sugar levels. Sound good? Purdue researchers have developed a new glucose sensor that can detect sugar concentrations in urine, tears, and saliva, which could mean no more finger sticks in the future.
Is there a better way to test glucose?
People with diabetes need to monitor their blood glucose daily as part of their standard care. For those with type 1 diabetes, at least three to four tests per day is typical, while those who have type 2 diabetes should do at least two finger pricks. Yet compliance is not good, with one study showing that up to 67 percent of patients don't routinely monitor their sugar levels.
In a study published in Diabetes Care, for example, nearly 1,900 people with diabetes were questioned about their compliance with recommended glucose monitoring. This was a self-report, so the actual figures could have been higher, but the reasons for noncompliance were sore fingers (492 patients), pain (428), inconvenience (347), fear of needles (117), and other (96; including cost).
The new biosensor developed by a Purdue research team is "a platform that might eventually help to eliminate or reduce the frequency of using pinpricks for diabetes testing," explained one of the team members, Jonathan Claussen, a former Purdue University doctoral student and now a research scientist at the US Naval Research Laboratory.
The new nanostructured biosensor is the first one of its kind, because it can detect glucose in four substances: urine, blood, saliva, and tears. In addition, the sensor does not involve a lot of processing steps, which means it is less expensive to produce than other sensors and thus better suited for commercial use.
Another advantage of the new sensor is its sensitivity: it can detect glucose in concentrations as low as 0.3 micromolar, which is superior to other sensors that are based on other materials such as graphene, carbon nanotubes, and metallic nanoparticles. The sensor also has an ability to distinguish between glucose and other substances that can cause interference in a glucose reading, such as uric acid and acetaminophen.
The diabetes test strips used in currently available glucose monitoring systems contain the enzyme glucose oxidase. Glucose in a blood sample first reacts with the enzyme and then sends a signal, which results in a reading. In the new biosensor system, the glucose oxidase attaches to platinum nanoparticles. After the enzyme transforms glucose to peroxide, a signal is sent.
It's uncertain how long it will be before a bloodless diabetes testing system can be in the hands of people with the disease. When it does become available, it will hopefully improve diabetes testing compliance and thus better management of the disease.
Burge MR. Lack of compliance with home blood glucose monitoring predicts hospitalization in diabetes. Diabetes Care 2001 Aug; 24(8): 1502-3
Claussen JC et al. Nanostructuring platinum nanoparticles on multilayered graphene petal nanosheets for electrochemical biosensing. Advanced Functional Materials 2012 Aug 21; 22(16): 3317