A luminescent one-dimensional covalent organic framework for organic arsenic sensing in water

Roxarsone (ROX) is a commonly used antibacterial and growth-promoting additive to animal feed. The development of an effective method for detecting ROX and its conversion products is of importance because of their potential harm to human health and ecosystem. Herein, we report the designed synthesis of a novel one-dimensional covalent organic framework (1D COF), named EP-COF, and its application as a fluorescent probe for ROX sensing. EP-COF is constructed based on imine linkages, exhibiting high crystallinity, strong fluorescence emission, and good dispersibility in water. It displays a remarkable capability to efficiently detect ROX, with an impressive detection limit of 4.5 nmol/L. Moreover, EP-COF also offers advantages of excellent selectivity, and high structural stability. This work not only presents a promising approach for the detection of harmful substances like ROX, but also serves as a valuable reference for exploring application of 1D COFs in chemical sensing.