A non-enzymatic glucose sensor with enhanced anti-interference ability based on MIL-53(NiFe) metal-organic framework
The non-enzymatic glucose sensors attractive vigorous attention owing to their low cost, storage convenience and reusability, however, the poor anti-interference caused by weak selectivity of traditional inorganic sensors toward glucose limits their practicability. In the present work, MIL-53(NiFe) metal-organic framework (MOF) is prepared on Ni foam to serve as a self-supported electrode for non-enzymatic glucoses sensors. Thanks to the abundant active sites in MIL-53(NiFe) MOF and its good stability in alkali solution, the sensors exhibit a high sensitivity (41.95 mA mM-1 cm-2) and a low detection limit (0.67 μM). Moreover, the molecular sieve effect of MIL-53(NiFe) MOF leads to a remarkable ability of anti-interference even the concentration of interferences reaching to 20% of glucose, a higher value than that in human serum. In addition, heat-treatment is carried out to remove the residual terephthalic acid in the MOF tunnels, and this promotes the detection linear range to 2~1600 μM. The reusability, reproducibility and long-term stability of the sensors are also studied, and the results imply a good practicability of the MIL-53(NiFe) MOF based sensors. Furthermore, the practicability of the sensors is verified by testing human serum samples. The results have a relative standard deviation of 2.73% with the value from hospital, and exhibit near 100% adding standard recoveries, indicating the good practicability of the sensors.