Michael reaction-assisted fluorescent sensor for selective and one step determination of catechol via bifunctional Fe-MIL-88NH2 nanozyme

The synthesized Fe-MIL-88NH 2 was used as a nanozyme and fluorescence probe to successfully construct a selective fluorescent sensing platform for one step determination of catechol. Fe-MIL-88NH 2 exhibited excellent peroxidase mimic property as well as fluorescence property. With the addition of H 2 O 2 and catechol, Fe-MIL-88NH 2 would catalyze the H 2 O 2 to form hydroxyl radicals ( OH). Then, the oxidation of catechol would be triggered by the formed OH, which resulted in the generation of 1, 2-benzoquinone. Afterwards, Michael reaction between the oxidation products of catechol (1, 2-benzoquinone) and Fe-MIL-88NH 2 ligands was triggered and then quenched the fluorescence of Fe-MIL-88NH 2 . The principle of the selective determination of catechol was due to the assistant effect of Michael reaction. Based on the above sensing mechanism, a fluorescent sensing platform for the determination of catechol was established. The limit of detection was 0.0913 μmol L −1 (3S 0, n=8 /K) within a fast response of 10 min. This simple and selective strategy, based on the Michael reaction and the superiority of Fe-MIL-88NH 2 nanozyme, provided a concise sensing platform for catechol determination, which broadened the scope of application of nanozyme and showed a great potential application for on-site testing in food and biology analysis.