On the Molecular Diffusion Dynamics Between Subcutaneous Tissue and Microneedles for Wearable Continuous Glucose Monitoring

Continuous glucose monitoring (CGM) is a commercially available biochemical sensor for diabetes management. A growing trend in this field is the transition from long needles to microneedles to reduce pain and avoid bleeding. A promising strategy for microneedle‐based CGM involves using hydrogel as a filler to bridge the interstitial fluid and externally deployed glucose sensors on the skin surface. However, the glucose diffusion dynamics, critical to the sensing process, remain poorly understood. In this study, we investigate the dynamics of glucose diffusion between subcutaneous tissue and hydrogel‐filled microneedles. Specifically, we examine how hydrogel thickness, microneedle size, and glucose concentration influence diffusion. This study provides an experimental reference to the wearable biosensor community researching microneedle‐based CGM.