Fluorescent selenium covalent organic framework sensor of ofloxacin antibiotics

As the main novel pollutants in water environment, antibiotics pose great threat to human-beings. It is of pivotal significance to develop sensitive and selective sensing materials to monitor them in natural environment. For this purpose, we design and synthesize Se-based covalent organic framework (TPE-BSD-COF). It showed excellent fluorescence quenching and linear relationship, rapid response, wide detection range, and low limit-of-detection (LOD) for ofloxacin. Most importantly, it demonstrated very good selectivity without response to other typical antibiotics. Besides, ofloxacin in real environment samples was detected and excellent recovery rates were obtained. We conducted in-depth structure-activity experiments and density-function-theory (DFT) theoretical studies to unearth the fluorescence quenching mechanism. Together, this work will provide new insights into the design of fluorescent COF sensors for the detection of various environmentally interested antibiotics pollutants.