Fabrication of a Stable Europium-Based Luminescent Sensor for Fast Detection of Urinary 1-Hydroxypyrene Constructed from a Tetracarboxylate Ligand

Abstract

A novel europium-centered metal–organic framework fabricated from a symmetric and rigid ligand with tetracarboxylate groups, 2,6-di­(2′,5′-dicarboxylphenyl)­pyridine (H4ddpp), has been synthesized solvothermally. Characterized by single-crystal X-ray diffraction, compound 1 features a 3D microporous structure with a butterfly-shaped trinuclear Eu3(COO)6 secondary building unit. Interestingly, three kinds of 1D open channels viewed in different directions in compound 1 are discovered, and the void ratio is calculated to be 47.5% by PLATON software. Solid-state luminescent experiments at 298 K reveal that compound 1 displays naked-eye characteristic red emission of Eu3+ ions monitoring the typical 5D0 → 7F2 transition. The exploration of luminescent sensing tests discloses that compound 1 has an outstanding capacity for recognizing urinary 1-hydroxypyrene (1-HP) with a quite fast response and high sensitivity, giving the quenching efficiency of 98.2% after the immersion time for just 1 min and 73.2% with the amount of 1-HP only 0.05 mg/mL. To our knowledge, it is the first reported Eu-MOF as an extremely fast-responsive and highly sensitive luminescent sensor for 1-HP which is interference-free from other urinary components. Furthermore, the successful preparation of the luminescent test papers makes compound 1 convenient, easy, and real-time in the application for sensing 1-HP in biomedical and biological fields.

Notably Stable Bifunctional Europium-Centered Metal–Organic Framework for Instant Sensing of Uric Acid and 1-Hydroxypyrene in Human Urine

“…The result indicates that the energy levels of LUMO of 1-HP and UA are higher than that of the ligand H 4 cdip, excluding the photo-induced electron transfer (PET) mechanism for sensing 1-HP and UA (Figure b). , Therefore, we speculate that energy transfer between compound 1 and the analytes (1-HP and UA) plays a vital role in such a luminescence-sensing behavior. Moreover, as depicted in Figure S12, the excitation peaks of compound 1 at different contents of 1-HP and UA (0–1.0 mg/mL) show no obvious shift, indicating that the quenching process for 1-HP and UA cannot be attributed to the static quenching mechanism. , In addition, the UV–vis absorption spectrum of 1-HP exhibits a distinct overlap with those of H 4 cdip and compound 1 , indicating that competitive absorption is another factor for the luminescence-quenching effect of 1-HP (Figure S13). However, there were no obvious overlaps between the absorption spectra of UA and compound 1 or H 4 cdip, eliminating the presence of competitive absorption in the luminescence detection for UA.…”

“…Moreover, as depicted in Figure S12, the excitation peaks of compound 1 at different contents of 1-HP and UA (0−1.0 mg/mL) show no obvious shift, indicating that the quenching process for 1-HP and UA cannot be attributed to the static quenching mechanism. 10,11 In addition, the UV−vis absorption spectrum of 1-HP exhibits a distinct overlap with those of H 4 cdip and compound 1, indicating that competitive absorption is another factor for the luminescence-quenching effect of 1-HP (Figure S13). 60 However, there were no obvious overlaps between the absorption spectra of UA and compound 1 or H 4 cdip, eliminating the presence of competitive absorption in the luminescence detection for UA.…”

“…Polycyclic aromatic hydrocarbons (PAHs) are a class of chemical carcinogens ubiquitously existing in the environment and daily life. PAHs are considered to be the leading class of carcinogens because of their powerful mutagenicity, teratogenicity, and carcinogenicity. , In consequence, it is of great significance to develop valuable materials and methods for the highly selective, sensitive, and fast detection of UA and 1-HP in human serum or urine.…”

Construction of High Quantum Yield Lanthanide Luminescent MOF Platform by In Situ Doping and Its Temperature Sensing Performance

“…In particular, the molar ratio of metal ions (Eu 3+ /Bi 3+ , Tb 3+ /Bi 3+ ) in Eu-Bi-SIP and Tb-Bi-SIP measured by ICP-OES is only 1%, which belonged to the extremely low Ln 3+ ion concentration doping. That means the very low concentration of the Ln 3+ doping shows high quantum yields and presents a significant advantage over most reported Ln-MOFs, especially Eu 3+ and Tb 3+ ions (Figure . − …”

Reversible Structural Transformation and Catalytic Potential of Lanthanide-Azobenzenetetracarboxylates

“…Inspired by potential applications in, for instance, gas storage and separation, , sensing, , proton conduction, and catalysis, − as well as the unique capability to be tailor-made, interest in coordination polymers (CPs), including metal–organic frameworks (MOFs), have grown exponentially. Properties and functions of CPs are well-acknowledged to be determined by, for example, metal coordination environment, functional groups decorated on the organic linker, and framework architecture and registration. − The change in these structural factors can therefore lead to the transformation of framework architecture and corresponding properties.…”