ScholarWorks@중앙대학교

초록

The demand for continuous, non-invasive biomarker monitoring in personalized healthcare has accelerated the development of energy-autonomous biosensing systems. Herein, we present a fully self-powered, wearable glucose biosensor that integrates microneedle (MN)-based electrochemical sensing with flexible thermoelectric energy harvesting. The platform employs a skin-conformable thermoelectric generator (TEG) composed of p-n bismuth telluride (Bi2Te3) thermoelements embedded within a stretchable Ecoflex matrix, which effectively converts skin-ambient thermal gradients into electrical power. A custom-designed miniaturized voltage regulation circuit regulates the harvested voltage, delivering a stable 0.4-0.8 V output sufficient to operate a chronoamperometric sensing module without external power sources. The MN working electrode is engineered with a hierarchical graphene interface and a conformal bimetallic Au/Pt thin film to enhance electroactive surface area, electron transfer kinetics, and enzyme immobilization capacity. Glucose oxidase (GOx) is subsequently immobilized onto the electrode surface to enable selective enzymatic oxidation of glucose, generating a quantifiable electrochemical signal. Among three evaluated MN geometries, the 1 mm tip height configuration demonstrated optimal dermal interfacing and electrochemical performance, yielding the highest current response. In vitro assessments in artificial interstitial fluid demonstrated a linear detection range of 4-24 mM glucose with high sensitivity and minimal cross-reactivity to interfering analytes. In vivo validation in a rat model confirmed strong correlation with blood glucose levels, demonstrating effective diabetes monitoting, excellent biocompatibility, and robust tissue integration. This work presents a potential platform for self-sustained, robust non-invasive glucose monitoring and sets a foundation for next-generation wearable biosensors in personalized medicine.

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