A Water-Stable Tb(III) Metal-Organic Framework with Multiple Fluorescent Centers for Efficient Self-Calibration Sensing Pesticides

摘要

Traditional single-fluorescence sensors have certain limitations in selectivity and sensitivity, and developing novel self- calibration probes is highly required. Herein, a novel water- stabilized lanthanide metal-organic framework (MOF) sensor (Tb-BDOA) was selected, and its multiple emission peaks were used to self-calibrate sensing pesticide. Tb-BDOA emits green fluorescence at 445 nm,488 nm,545 nm,587 nm and 621 nm under the excitation of 280 nm. Different pesticides will cause different changes in the emission peaks of Tb-BDOA, so as to conveniently distinguish different pesticides and displays self- calibration fluorescent response to nicosulfuron (NSF) and thiamethoxam (TMT). Besides the unique combination of each pesticide and ligand!Tb(III) emission intensity ratio showed significant correlation, which realized specific two-dimensional fingerprint recognition. At the same time, 3D code recognition is realized by drawing the changes of two ratios under different concentrations. As a result, the novel self-calibration sensor demonstrates effective recognition of NSF and TMT with excellent sensitivity and selectivity as well as great recycling ability. This provides a promising strategy for the development of new self-calibrating sensors.