A novel reversible-responsive ratiometric fluorometry based on an anthracene-based imidazolium ionic liquid and Eu3+-based lanthanide coordination polymers for selective sensing tetracycline in foods and waters

Abstract

Detecting tetracyclines' (TC) residues is of great significance for evaluating the food and environmental safety. Herein, we pioneered a reversible-responsive ratiometric fluorometry by integrating the red fluorescence of Eu³⁺/GMP lanthanide coordination polymers (Eu³⁺/GMP LCPs) with the blue fluorescence of an anthracene-based imidazolium ionic liquid (ABIIL). In the presence of TC, the fluorescence of ABIIL was quenched by TC via the inner-filter effect and photoinduced electron-transfer process, but that of Eu³⁺/GMP LCPs was enhanced owing to the antenna effect between Eu³⁺ and TC. Based on the reversible variations of the fluorescence signals, a fluorescent assay based on ABIIL-Eu³⁺/GMP LCPs was engineered to detect TC with satisfactory sensitivity and selectivity. A good linearity for TC was acquired from 0 to 50 μM with the detection limit of 3.0 nM and the significant color changes. Therefore, the assay was a promising approach for the visual detection of TC in complex media