摘要
In this research,a hydroxyl group functionalized metal-organic framework(MOF),UiO-66-(OH)_(2),was synthesized as a "on-off-on" fluore scent switching nanoprobe for highly sensitive and selective detection of Fe^(3+),ascorbic acid(AA) and acid phosphatase(ACP).UiO-66-(OH)_(2) emits yellow-green light under ultraviolet light,when Fe^(3+) was added,Fe^(3+) was chelated with hydroxyl group,the electrons in the excited state S_1 of the MOF transferred to the half-filled 3 d orbits of Fe^(3+),resulting in fluorescence quenching because of the nonradiative electron/hole recombination annihilation.AA could reduce Fe^(3+) to Fe^(2+),which can destroy the electron transfer between UiO-66-(OH)_(2) and Fe^(3+) 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.
基金
supported by grants awarded by the National Natural Science Foundation of China(Nos.21505084,21775089)
Natural Science Foundation Projects of Shandong Province(No.ZR2014BM029)
Key Research and Development Program of Shandong Province(No.2017GSF19109)
Innovation Project of Shandong Graduate Education(No.SDYY16091)
Outstanding Youth Foundation of Shandong Province(No.ZR2017JL010)。
