Tiny digital needles penetrate the skin in a painless and non-invasive manner to detect real-time data about the body's biochemical status, such as glucose content, pH, or the presence of specific enzymes or proteins. The needles "light up" or not depending on the presence and concentration of the chemical to be detected, generating a QRcode that can be read using an app. As a result, we can immediately determine the concentration of the desired substance. It is the most recent frontier of precision medicine, conducted by Giuseppe Barillaro's team in the laboratories of the Department of Information Engineering at the University of Pisa. The research was published in Advanced Materials. Within the European project ALERT, coordinated by the University of Pisa, researchers employ microneedle technology to identify Alzheimer's signs several years before symptoms appear. "Real-time biochemical detection is essential for personalized and precision medicine", explains Giuseppe Barillaro, professor of electronic engineering at the University of Pisa, "however current implantable biosensors are difficult to use for real-time human monitoring, because they require careful calibration and also detect only one element at a time. Our study instead proposes fluorescent digital microneedles arranged in multiple lines forming a matrix, each with only two states: on or off. Each needle has a different threshold value and lights up when it detects a concentration above threshold of the target substance, such as glucose or pH. This eliminates any need for calibration. Ultimately, the sequences of on and off needles form a QR code that can be scanned via an app, providing direct information on substance concentrations. Each needle can also be designed for a different substance, allowing simultaneous analysis, for example, of glucose concentration and pH". The QRcode generated by the microneedles provides a direct and quantitative representation of biochemical information, facilitating decentralized and wearable diagnostics and personalized medicine, and offering vast potential for medical applications, including the early detection of cancer, sepsis and infectious diseases, and also for applications in environmental monitoring, precision agriculture and food safety.