➀ Researchers at Duisburg-Essen University have developed a new method for measuring blood sugar levels at the fingernail without a needle. The technology uses Terahertz waves that penetrate the fingernail and reflect off the nail bed.

➁ The Terahertz technology is based on electromagnetic waves with a wavelength between microwave and infrared radiation, allowing for detailed analysis of biological tissues without damaging them.

➂ The sensor, which is only a few mm2 in size, could be integrated into everyday items like keychains or artificial fingernails.