An electronic biosensor has been developed that can be implanted in diabetes patients to continuously monitor their glucose levels. This method may replace finger-pricks that diabetics often undergo to keep a tab on their fluctuating blood sugar levels can be a thing of past, according to a report in December 2019. Researchers from the King Abdullah University of Science and Technology (KAUST) in Saudi Arabia, including a scientist who joined the Central Electrochemical Research Institute (CECRI), Karaikudi, in 2018, have developed the enzymatic fuel cell which powers the device. The related article was published in the Nature Materials journal.
About the Biosensor
The new electronic biosensor pairs an electron-transporting polymer with an enzyme that extracts electrons from its reaction with glucose in bodily fluids to power itself. Bodily fluids such as human saliva can not only power the device, but also give a count of blood sugar levels of the users. The implantable glucose-sensing devices that are used at present need batteries that have to be recharged or replaced, which renders the implantation a complicated procedure.
Globally, the market for biosensors that contribute to healthcare industry is around $13 billion and is still growing at a rate of 9 to 12 per cent annually. Glucose biosensors account for nearly 85 per cent of this market.
Quick, accurate and early detection of abnormalities in metabolism is of importance to monitor, control and prevent many diseases, including diabetes.
Details
The researchers were keen on a better alternative to both finger-pricking devices and battery-operated implantable devices that need regular replacement, to monitor glucose levels. It stumbled upon a polymer developed by another scientist at the university. This polymer was an n-type semiconductor which can accept and transport electrons.
To make the polymer work as a self-powered glucose sensor, the scientists coupled it with an enzyme called glucose oxidase, which extracts electrons from its reaction with glucose. Subsequently, they demonstrated its ability qualitatively and quantitatively. The biofuel cell is the first demonstration of a completely plastic electrocatalytic energy generation device operating using bodily fluids. It has been found to generate microwatt per square centimetre range electricity which is sufficient enough to operate the sensor.
Glucose sensing and power generation are two examples of the applications possible when a synthetic polymer communicates effectively with a catalytic enzyme-like glucose oxidase.