Scientists at the University of Cambridge have developed a compact optical sensor costing about $10 that could bring laboratory-grade testing to wearable devices, potentially allowing people to monitor blood glucose without needles.
Which essentially means the low-cost sensor could one day let people use a smartwatch to monitor blood sugar, hydration and alcohol levels without needles or laboratory tests.
The device, known as a “convolutional spectrometer”, analyses how light interacts with materials to reveal their chemical composition, offering a smaller and cheaper alternative to conventional laboratory equipment.
Optical spectrometers are widely used in medicine, manufacturing and environmental research, but shrinking them has traditionally reduced their accuracy or limited the range of measurements they can perform.
The Cambridge team developed a different approach that uses a mathematical technique called convolution to analyse incoming light, enabling the sensor to deliver precise results with relatively little computing power.
In tests, the device correctly classified plastics, medicines, coffee, flour and tea, achieving 100% accuracy in identifying the materials included in the experiments.
The researchers also tested the technology on biological measurements, demonstrating that it could measure skin moisture, blood alcohol, lactate and glucose under conditions designed to resemble real physiological environments.
In one demonstration, the sensor tracked glucose without penetrating the skin over an extended period in a single participant, although further research is needed to establish whether the approach can work reliably in practical medical settings.
The device measures only a few centimetres across and can process measurements in less than a second, making it a potential component for smartwatches and other portable electronics.
Its developers believe the technology could eventually help people with diabetes monitor blood sugar, while also enabling wearable devices to track hydration, alcohol levels and other indicators of health.
Beyond healthcare, inexpensive sensors could be deployed across factories to check product quality, identify materials and monitor changes in food freshness or environmental conditions.
The findings, published in Nature Photonics, suggest that a relatively simple design could make sophisticated optical measurements cheaper and more widely available, but commercial adoption will depend on further development and testing.
