A covalent organic framework with hydrazone bond for efficient enrichment of phenolic pollutants

Synthesize A covalent organic framework material (DTB-COF) with hydrazone bond. • The phenolic pollutants (CPs) in juice, milk and honey samples were determined. • DTB-COF effectively adsorbs CPs via the synergistic actions of π-π stacking, hydrophobic, and hydrogen bonding. To address the challenges of phenolic pollutants (PPs), including high toxicity, poor degradability, and difficulty in trace enrichment, this work developed a hydrazone-linked covalent organic framework (DTB-COF). DTB-COF features abundant N H hydrogen bond donors and C N hydrogen bond acceptors within its pores, enabling synergistic adsorption of PPs through hydrogen bonding, hydrophobic interactions, π-π stacking, and pore filling. Employing DTB-COF as a solid-phase extraction adsorbent combined with high-performance liquid chromatography, we established a quantitative detection method. In juice, milk, and honey, the limits of detection were 0.12–0.22, 0.29–0.58, and 0.53–1.51 ng mL −1 , respectively; the spiked recoveries ranged from 87.0%–112.0%, 89.1%–112.9%, and 87.6%–112.9%, respectively, with relative standard deviations below 6.89%. This method demonstrates high accuracy and good reproducibility, effectively addressing the limitations of traditional adsorbents, such as low capacity and poor reproducibility, offers a reliable and efficient strategy for the trace analysis of PPs in food matrices. Download: Download high-res image (111KB) Download: Download full-size image