Graphene-based biosensor for detecting diabetes
doi:10.1038/nindia.2016.41 Published online 28 March 2016
Researchers have fabricated a sensitive biosensor that can detect minute traces of glycated haemoglobin, a marker of diabetes, in human blood1. This sensor is potentially useful for diagnosing the onset of diabetes.
Current techniques for diagnosing diabetes measure glucose levels in blood but are time-consuming and complex.
To devise rapid way to diagnose diabetes, the researchers synthesized a nanocomposite by attaching gold nanoparticles to nitrogen-doped graphene nanosheets. They then attached the enzyme fructosyl amino acid oxidase to this nanocomposite and deposited it on a fluorine-doped tin oxide glass electrode.
To probe the efficiency of the biosensor to monitor glycated haemoglobin, it was exposed to whole blood samples from diabetic and healthy individuals. The biosensor detected higher levels of glycated haemoglobin in the blood samples from diabetics than in those from healthy individuals.
The biosensor selectively detected glycated haemoglobin even in the presence of interfering agents such as ascorbic acid, uric acid, urea, bilirubin and glucose, which are usually found in human blood. The biosensor retained 50% of its original sensitivity after being used 100 times over 4 months.
Glycated haemoglobin reflects average plasma glucose over the 8 to 12 weeks that precede a blood test. “Since it can perform measurements at any time of the day and does not require any special preparation such as fasting, this biosensor may offer a simple way to monitor diabetes,” says Utkarsh Jain, one of the researchers.