3D-printed biocompatible hollow microneedle-based electrochemical sensor for wireless glucose monitoring

Wearable electrochemical sensors have aroused tremendous attention due to their great potential for in situ and continuous assessment for glucose monitoring. Conventional fingerstick test is the easiest and most efficient method for glucose evaluation, but invasive and painful. Here we introduce a wearable and user-friendly microneedle-based electrochemical sensor, fabricated via resin 3D printing and integration of a single-atom nanozyme-modified electrode, offering excellent biocompatibility, high sensitivity and superior selectivity for glucose monitoring. This minimally invasive electrochemical sensor demonstrates the capability to extract artificial interstitial fluid using biocompatible hollow microneedles and a finger-activated pump, enabling continuous monitoring of dynamic glucose concentration changes. This electrochemical sensor exhibits remarkable sensitivity and exceptional selectivity, with a linear range of 0.1 μM to 50 mM and a limit of detection of 0.059 μM, attributed to the incorporation of single-atom nanozymes with peroxidase-like enzymatic activity. The glucose concentration data are wirelessly transmitted to a mobile app in real time, offering user-friendly access and facilitating remote monitoring. The described electrochemical sensor presents the possibilities for point-of-care health monitoring applications.