Ultrasensitive Eu-Based MOF Luminescence Sensor for Clenbuterol Visible Recognition

Abstract

Clenbuterol (CLB) as an illegal feed additive may cause a great security risk to food safety. However, convenient and efficient detection means for CLB in practical application remain a formidable challenge. Herein, a stable Eu-based organic framework {[H2N­(CH3)2]2[Eu2(ttca)2]·H2O}n (compound 1) (H4ttca = [1,1′:2′,1″-terphenyl]-4,4′,4″,5′-tetracarboxylic acid) has been harvested, exhibiting excellent chemical stability and thermal stability. Luminescence investigation reveals that compound 1 can sensitively and selectively detect CLB without being affected by different components from simulated serum and urine (limit detection: 22.7 nM). Furthermore, sensor 1 can also be applicable to CLB recognition in real swine feeds, presenting excellent anti-interference performance. The good cyclicity of compound 1 endows CLB determination with many advantages: low cost, high stability, and simplicity. Importantly, in view of the indication of the luminescence color (red to blue), test membranes were fabricated and employed for convenient and fast CLB detection, providing a valuable scheme for the visual monitoring of CLB in meat products. This work enriches rare earth metal compounds and luminescence sensor portfolios and breaks the concentration record (nM) for detecting CLB compared with reported complex materials, providing an effective monitoring platform for CLB visually.

Fabrication of a Terbium-Functionalized Cadmium Organic Framework with Proper Energy Levels as a Ratiometric Probe of an Anthrax Biomarker

“…Herein, a butterfly shaped aromatic tetracarboxylic ligand [1,1′:2′,1″-terphenyl]-4,4′,4″,5-tetracarboxylic acid (H 4 TTCA) was selected to prepare a Cd-based MOF (Cd 2 (TTCA)­(H 2 O) 4 ·H 2 O, denoted as TTCA-Cd), owing to its abundant coordination sites, rich coordination modes, and aromatic character, which are favorable to the stability of MOFs. , For the purpose of developing a ratiometric probe, a Tb­(III) ion was introduced in this MOF by the solvothermal method, and the obtained TTCA-Cd@Tb displayed not only the ligand-centered emission but also the typical emissions of Tb­(III). It was revealed that it could be used as a rational fluorescence probe of DPA with a very low LOD of 7.14 nM, a large detecting range (0–200 μM), and high selectivity, which is a promising DPA fluorescent probe (Scheme ).…”