A Silk-Microneedle Patch to Detect Glucose in the Interstitial Fluid of Skin or Plant Tissue

Glucose is critical to all organisms. Herein, we developed a wire electrode embedded microneedle patch (WEMNP) for in situ real-time detection of glucose in the interstitial fluid (ISF) of skin or plant tissues with minimal invasiveness. WEMNP is made of proline treated silk fibroin proteins, which provide good mechanical strength (0.75 N/microneedle) for tissue penetration and desirable bioelectronic interface for fast and high-fidelity detection. WEMNP shows specific and linear response to glucose between 3 and 18 mM for detection in skin ISF with a sensitivity of 21.21 nA/mM and between 30 and 180 mM for detection in plant ISF with a sensitivity of 1.22 nA/mM. Such self-administrable WEMNP could be instrumental to long-term home-based management for chronic diseases and to smart agriculturing.