Recyclable Eu3+ functionalized Hf-MOF fluorescent probe for urinary metabolites of some organophosphorus pesticides.

A luminescent metal-organic framework Eu3+ functionalized Hf-MOF (Eu3+@1) is designed through post-synthesis modification (PSM) and utilized as a probe for detecting p-nitrophenol (PNP, the urinary metabolite of parathion, methyl-parathion and EPN) and 3-methyl-4-nitrophenol (PNMC, the urinary metabolite of fenitrothion). The apparent quenching effect in urine is observed from the Eu3+@1 with the addition of organophosphorus metabolites. The fluorescent probe has several appealing merits, such as high selectivity, excellent sensitivity (0.36 μg mL-1 for PNP, 0.41 μg mL-1 for PNMC), fast response time (less than 1 min) and easy preparation. Linear correlation between the fluorescence intensity of Eu3+@1 and the concentration of PNP and PNMC are from 0.005 to 0.15 mg mL-1 and 0.005-0.30 mg mL-1, respectively. Furthermore, this fluorescent material also demonstrated the possibility for recycling. It is a prominent candidate for potential application in personalized monitoring the internal dose of human exposure to some organophosphorus pesticides.