Abstract: Efficient glucose monitoring is of utmost significance for diabetes management and the prevention of complications. In this study, a ZIF-8-Pt@MWCNTs composite was developed for modification working electrod of a non-enzymatic glucose biosensor. The zeolitic imidazolate framework?8 (ZIF?8) shell acts as a molecular sieve and enrichment layer, allowing glucose to reach the platinum (Pt) core while blocking interferents, thus lowering overpotential and improving selectivity. The biosensor exhibits a linear range of 0.1-30 mM (R2 > 0.99), a geometric-area sensitivity of 9.31 μA·mM?1·cm?2, a detection limit of 0.09 mM, and six-week storage stability. Interference tests in the presence of glucose show > 90% current retention with ascorbic acid (AA), dopamine (DA), uric acid (UA), sodium chloride (NaCl) and bull serum albumin (BSA), spike recovery > 95%, and > 93% retention after 7200 s in glucose mix and > 90% after 24 h exposure. A portable device integrating a 15 × 15 porous microneedle array, the biosensor, and a 13 g printed circuit board (PCB) was constructed. The PCB converts current directly to glucose concentration, eliminating a bulky workstation, and allows independent electrode replacement. In vivo monitoring in rats over 4.5 and 12 h tracked glucose closely with a commercial glucometer, with mean absolute relative difference (MARD) < 10% and all readings in Zone A of Clarke error grid analysis (CEGA), indicating clinical potential. This smart microneedle system enables painless, minimally invasive, accurate, and periodic glucose monitoring.

Keywords: microneedle, non-enzymatic glucose biosensor, periodic glucose monitoring