A metal organic framework based fluorescent sensor for selective and enzyme free detection of glucose

In this study, a non-enzymatic, fluorometric sensing platform based on NH₂-MIL-125(Ti) was developed for the detection of glucose. The synthesized metal–organic framework (MOF) exhibited a strong fluorescence response upon interaction with glucose. Glucose concentrations ranging from 1–333 µM were investigated, with a validated linear response observed in the range of 140–333 µM and a calculated limit of detection (LOD) of 43.5 µM. Additionally, the MOF demonstrated sensitivity toward hydrogen peroxide (H₂O₂), a common byproduct of glucose oxidation. Comprehensive characterization through XRD, FTIR, TGA, BET, and FESEM confirmed the structural integrity, thermal stability, and successful incorporation of glucose. The observed fluorescence enhancement behavior and linear Stern–Volmer relationship underscore the sensing performance of MOF. The effect of MOF precursors was also investigated, revealing that the amino-terephthalic acid linker is primarily responsible for the enhanced fluorescence detection. Furthermore, selectivity tests conducted in the presence of various competing analytes, including NaCl, glycine, urea, and sucrose, demonstrated a preferential fluorescence response toward glucose among the tested analytes. These findings demonstrate the potential of NH₂-MIL-125(Ti) as an enzyme-free fluorescent sensor for glucose detection. However, further validation under near-physiological conditions and in biological samples is required to assess its suitability for biomedical applications.