Rapidly enrichment and detection of per-and polyfluoroalkyl substances in foods using a novel bifunctional covalent organic framework

Per- and polyfluoroalkyl substances (PFASs) are extensively found in foods, posing potential toxicity to humans. Therefore, rapid analysis and monitoring of PFASs in foods are crucial for public health and also a challenge. To detect trace PFASs in foods, construction of sorbents with multiple interactions could be an effective approach. Herein, a cationic-fluorinated covalent organic framework (CF-COF) was prepared by post-modification and used as a magnetic solid-phase extraction adsorbent for adsorption of PFASs. By combining magnetic solid-phase extraction based on CF-COF with liquid chromatography-tandem mass spectrometry (LC - MS/MS), a novel method was developed for determination of eight long-chain PFASs in foods. Under optimized conditions, the method exhibited low detection limits (0.003-0.019 ng/g) and satisfactory recovery rates (73.5-118%) for PFASs. This study introduces a novel idea for the development of adsorbents targeting PFASs, along with a new analytical method for monitoring of PFASs in foods.