Preparation of fluorescent probes based on covalent organic frameworks (COFs) and their application in the detection of nitro-containing pesticide residues

is significantly reduced or even quenched, thereby realizing the quantitative detection of PCNB. Experimental results show that this fluorescent probe exhibits high sensitivity (limit of detection, LOD = 0.46 µM; limit of quantification, LOQ = 1.53 µM), a wide linear range (1.53-40 µM), and good selectivity in PCNB detection. Furthermore, the material has excellent chemical stability and hydrophilicity, providing a new approach for the detection of PCNB in aqueous environments. This study not only expands the application potential of COF materials in the field of pesticide detection but also provides technical references for pesticide residue monitoring and food safety supervision.