Construction of Eu3+ modified covalent organic framework and fluorescence detection of L-lysine

Abstract

L-Lysine is an essential amino acid that cannot be synthesized artificially and must be obtained through dietary sources. Therefore, it is crucial to detect its content in food. In this study, we present a simple and effective method for the chiral fluorescence recognition of L-lysine utilizing a chiral covalent organic framework. Initially, we synthesize a TAB-DFP-COF incorporating a pyridine group, which is subsequently modified with Eu³⁺ to produce the Eu³⁺@TAB-DFP-COF ratiometric fluorescent sensor. This sensor is capable of compensating for various factors unrelated to the target due to its built-in self-correction function. This fluorescent sensor is not only easy to synthesize but also exhibits rapid response time. Additionally, it demonstrates good selectivity and high sensitivity. This work represents the first application of covalent organic framework materials for the detection of L-lysine without chiral modification, thereby offering a novel approach for the detection of chiral amino acids in the future.