Metal-organic framework as a multi-component sensor for detection of Fe3+, ascorbic acid and acid phosphatase

In this research, a hydroxyl group functionalized metal-organic framework (MOF), UiO-66-(OH)(2), was synthesized as a on-off-on fluorescent switching nanoprobe for highly sensitive and selective detection of Fe3+, ascorbic acid (AA) and acid phosphatase (ACP). UiO-66-(OH)(2) emits yellow-green light under ultraviolet light, when Fe3+ was added, Fe3+ was chelated with hydroxyl group, the electrons in the excited state S-1 of the MOF transferred to the half-filled 3d orbits of Fe3+, resulting in fluorescence quenching because of the nonradiative electron/hole recombination annihilation. AA could reduce Fe3+ to Fe2+, which can destroy the electron transfer between UiO-66-(OH)(2) and Fe3+ after AA adding, resulted in nonoccurrence of the nonradiative electron transfer, leading to the recovery of UiO-66-(OH)(2) fluorescence intensity. The probe can also be used to detect ACP based on the enzymolysis of 2-phospho-L-ascorbic acid (AAP) to produce AA. Benefitting from the hydroxyl group and the characteristics of UiO-66, including the high porosity and large surface area, the developed UiO-66(OH)(2) showed extensive advantages as a fluorescent probe for detection of multi-component, such as high sensitivity and selectivity, colorimetric detection, fast response kinetics and easy to operate, economical and secure. This is the first time to use active group functionalized MOFs as a multicomponent sensor for these three substances detection. (C) 2020 Chinese Chemical Society and Institute of Materia Medica, Chinese Academy of Medical Sciences. Published by Elsevier B.V. All rights reserved.

Automated summary

A hydroxyl group functionalized metal-organic framework UiO-66-(OH)(2) was synthesized for sensitive and selective detection of Fe3+, ascorbic acid, and acid phosphatase. The probe exhibited advantages such as high sensitivity and selectivity, colorimetric detection, fast response kinetics, and ease of operation.