Electrocatalytic Zeolite 3A-based sensor for ultra-sensitive glucose monitoring

Non-enzymatic glucose sensors allow ultralow trace detection in saliva and other biofluids of significant interest. We report a novel zeolite 3A–based non-enzymatic glucose sensor for indirect detection via zeolite electrocatalysis, leveraging its porous structure and ion-exchange properties for sensitive, stable sensing. A flexible sensor was fabricated by facile deposition of a zeolite/vegetable oil mixture onto a silver-coated Kapton substrate. The proposed transduction mechanism is based on the glucose-to-fructose isomerization, with charge variation mediated by the rapid deprotonation of hexoses, a process significantly faster than isomerization and closed-hexose anion formation. the sensor exhibited significantly higher sensitivity at lower glucose concentrations of 6.68 μA·mM -1 ·cm -2 . At lower concentrations, the linear regression coefficient was R 2 = 0.93, whereas at glucose concentrations above 2 mM, the sensitivity was set to 1.00 μA·mM -1 ·cm -2 .correlation coefficient decreased to R 2 = 0.87. The limit of detection (LOD) was determined to be 0.1 μM. Overall, the wide linear range, cycle-to-cycle stability, and strong low-concentration sensitivity achieved here lay the groundwork for future validation in non-invasive biological matrices. • Frequent glucose monitoring remains a critical challenge in the advancement of next-generation glucometers. • A novel non-enzymatic glucose sensor is presented, exploiting the porous structure, ion-exchange capacity, and electrocatalytic activity of Zeolite LTA type 3A. • The sensor features a facile and low-cost fabrication process, producing a sensitive nanoporous layer on a silver-coated substrate. • Glucose detection is achieved indirectly through the electrocatalytic response of Zeolite 3A in alkaline media.