In order to monitor their blood glucose levels, diabetics typically have to perform painful and inconvenient finger-prick blood tests – in some cases, several times a day. Using an implantable glucose-monitoring sensor is one alternative, although it must be surgically installed and subsequently removed for replacement. Another option may be on the way, however, in the form of a device that simply shines a laser on the user's finger.
Known as GlucoSense, the system was developed by Prof. Gin Jose and his team at the University of Leeds.
To use it, patients simply place the pad of their finger against a small glass window on the device. A low-powered laser beam is then projected through that window, and into their finger. Some of that light is absorbed by glucose in the bloodstream, and some is reflected back down onto the window.
Ions on the window glass surface subsequently fluorescence in infrared when exposed to that reflected light – the more light that hits them, the longer they glow. By measuring the duration of that fluorescence, a processor in the device is able to determine how much of the original laser light was absorbed by glucose, and can thus deduce the amount of glucose in the bloodstream. The whole process takes less than 30 seconds.
After a period of clinical trials and commercial development by spinoff company GlucoSense Diagnostics, it is hoped that two versions of the device will be commercially available – a computer mouse-sized tabletop unit, and a wearable device that measures glucose levels continuously.
"As well as being a replacement for finger-prick testing, this technology opens up the potential for people with diabetes to receive continuous readings, meaning they are instantly alerted when intervention is needed," says Jose. "This will allow people to self-regulate and minimize emergency hospital treatment. This wearable device would then be just one step from a product which sends alerts to smart phones or readings directly to doctors, allowing them to profile how a person is managing their diabetes over time."
Scientists at Princeton University are currently exploring similar technology, while researchers at Google, Fraunhofer and Microsoft are developing non-invasive sensors that measure glucose content in tears or sweat.
Source: University of Leeds
