Room-temperature synthesis of flower-shaped covalent organic frameworks for solid-phase extraction of quinolone antibiotics.

The facile fabrication of covalent organic frameworks (COFs) is significant for exploring and promoting their application. In this study, TAPA-TFPB-COFs with flower-shaped morphology, good crystallinity, and high surface area was prepared via a facile room-temperature method. The as-synthesized TAPA-TFPB-COFs exhibited great adsorption capacity towards quinolone antibiotics (QAs) and satisfying reusability. Utilizing the TAPA-TFPB-COFs as solid-phase extraction cartridge packing and liquid chromatography-tandem mass spectrometry as detector, a reliable and ultrasensitive method for the assay of QAs was developed. The linearity ranges of QAs extended from 0.5 to 200 ng L with correlation coefficients higher than 0.9974, and the limits of detection varied from 0.02 to 0.11 ng L. The intra-day and inter-day precision were lower than 10.8% and 6.7%, respectively. The applicability of the developed method was evaluated through analyzing of tap water, spring water, chicken, and fish samples. The recoveries of QAs in spiked water and food samples varied from 80.0% to 107.6%. The reliability of the developed method was further verified by the accurate detection of QAs in a fish certified reference material.