Stick-and-sensing microneedle patch for personalized nutrition management

The focus of the next-generation healthcare system has moved forward from single disease detection to comprehensive health interpretation, namely, from disease diagnosis to prophylaxis via the early management of sub-health status. Among the technologies, microneedles have emerged as an efficient and powerful tool to realize painless and real-time sensing in the interstitial fluid (ISF), offering promising solutions for dynamic and direct reflection of nutritional profiles. Herein, we present a film-like, multifunctional microneedle patch, that is composed of three laser-induced graphene (LIG) based electrodes for minimally invasive and timely detection of glucose and vitamin C in the ISF. The microneedle patch is simply fabricated with a thickness of ∼0.25 mm polyimide (PI) film by a commercial laser platform, where laser-engraving is operated to form graphene electrodes, and laser-cutting accounts for the needle-tip shaping. Such fast, low-cost, and scalable manufactured microneedle patches showed excellent performance for electrochemical sensing and therefore allowed reliable on-the-tip monitoring of changes in glucose and vitamin C levels. Long-term studies in vivo and demonstrations in planta indicated the great promise of our microneedle patch to revolutionize dietary guidelines based on individualized status for effective nutrition management.