By application of a straightforward postsynthetic modification strategy, a luminescent lanthanide-based MOFs hybrid material, Tb(III)@MOF-SO, is first fabricated by loading Tb(III) ions into the pores of Zn-based MOF-SO. This hybrid system is constructed on notable and specific luminous sensitization of MOF-SO to Tb(III) ions. The further study shows that bi-metal-loaded Eu(III)/Tb(III)@MOF-SO exhibits a Tb(III)-induced luminescence of Eu(III) ions, and the emissions of it all fall in the white region by altering the ratio of Eu(III)/Tb(III) ions and the excitation wavelengths. A kind of white-lighting thin film based on Eu(III)/Tb(III)@MOF-SO exhibits dazzling white light when excited at 295 nm ( X = 0.338, Y = 0.323). Furthermore, the Tb(III)@MOF-SO is first developed as a fluorescence sensor specifically toward biomarker of benzene, trans, trans-muconic acid ( tt-MA), based on fluorescence quenching. This reusable sensor with high water tolerance and photostability displays excellent selectivity and sensitivity with a detection limit as low as 0.1 ppm, while being provided with the high antijamming of other urinary chemicals. These results make the sensor has the potential for the practical detection of tt-MA in a urine system. The possible quenching mechanisms are also investigated in detail.

A novel three-dimensional microporous framework, [Tb­(pddb)­phen­(ox) 0.5 ] n (Tb-MOF), was synthesized hydrothermally with V-shaped 4,4′-(pyridine-2,6-diyl)­dibenzoic acid (H2pddb), oxalate (ox), and 1,10-phenanthroline (phen). The framework of Tb-MOF features one-dimensional channels functionalized with pyridine-N Lewis base groups and the absence of coordinated and lattice water molecules in the structure. The Tb-MOF exhibits high thermostability (up to 385 °C) and chemical stability in a wide pH range (4–11) and common organic solvents as well as boiling water. The luminescence investigations of the Tb-MOF in common solvents, water with different pH values, and inorganic ions were performed. Results show that the Tb-MOF has high luminescence stability and the ability to probe Fe3+ ions. Significantly, the Tb-MOF with particularly high water stability can be first developed as a highly selective and sensitive luminescent sensor for the biomarker 2-thiazolidinethione-4-carboxylic acid (TTCA) via fluorescence quenching. The low detection limit (1 ppm), reusability, and high antidisturbance together make the Tb-MOF become a promising sensor for the practical detection of TTCA in urine systems, and for the first time realize the detection of urinary TTCA through fluorescence spectrometry based on an Ln-MOF sensor.

Covalent organic framework (COF) nanosheets (NSs) are a new member in the family of two-dimensional (2D) nanomaterials that received increasing attention. The ability to prepare COF NSs with rapid acquisition is of great importance to explore their distinctive properties and potential applications. Herein, we elaborate design a new COF hybrid material EB-TFP:Eu­(BTA)4 as a sensing platform. In the process of ratiometric fluorescence detection of 5-fluorouracil (5FU), an anticancer drug, we realize the preparation of COF NSs. Interaction occurs between 5FU and COF hybrid material, where the interlayer π–π stacking of COF was weakened, benefiting the exfoliation of bulk COF to acquire 2D COF NSs. This strategy provides not only a sensitive and selective 5FU sensor but also a significant inspiration for engineering 2D COF NSs.

A novel two-dimensional Cd-based metal–organic framework (MOF), [Cd­(pddb)­H2O] n (Cd-MOF), has been hydrothermally synthesized using the V-shaped ligand 4,4′-(pyridine-2,6-diyl)-dibenzoic acid (H2pddb) and structurally characterized. The framework exhibits fascinating one-dimensional in-plane channels functionalized with active pyridine-N sites. The as-synthesized Cd-MOF exhibits excellent water and chemical stability. Furthermore, a simple and nondestructive coordinated postsynthetic modification method has been applied to Cd-MOF to obtain a class of MOF hybrids functionalized by lanthanide ions. More interestingly, Eu3+@Cd-MOF can act as a dual-emissive ratiometric fluorescent probe for 2-(2-methoxyethoxy) acetic acid (MEAA), a metabolite of 2-(2-methoxyethoxy) ethanol, which could result in DNA damage and teratogenic and developmental toxicity. During the sensing process, the fluorescence sensor exhibits notable water tolerance, reusability, and a low detection limit (8.5 μg mL–1). In addition, the chemical substances in human urine and serum do not interfere with the fluorescence quenching process, which makes it possible for the fluorescent probe to be applied in the detection of MEAA in human urine and serum systems. The possible sensing mechanism is also studied and discussed in detail.

Four new MOFs containing transition metals and mixed ligands were synthesized. Then Ln(iii)@4 hybrids are successfully fabricated by cation-exchange. Significantly, Tb(iii)@4 can be first regarded as an efficient sensor for biomarker dichloroanilines.