A hydrophobic NH2[email protected]COF hybrid was successfully fabricated and explored as a promising SPE sorbent.

The NH2[email protected]COF hybrid exhibited better extraction performance than NH2-UiO-66 and HCOF via synergistic effects.

A sensitive detection method was established for analysis of flavonoids in food samples.

Metal-organic framework (MOF) and covalent organic framework (COF) exhibit excellent extraction performance in sample pretreatment, but their wider application is hindered by some inherent drawbacks. Herein, we successfully synthesized a novel [email protected] hybrid material with large specific surface area, good chemical stability and reusability, which is suitable as a solid phase extraction (SPE) sorbent for the efficient extraction of flavonoids. Importantly, due to the synergistic effect, the obtained [email protected] hybrid material showing a higher extraction efficiency than individual MOF and COF. This is mainly due to the obtained [email protected] hybrid material combines the high specific surface area of MOF and multiple interactions (hydrophobic interaction, hydrogen bonding and π-π stacking interaction) with flavonoids conferred by the COF structure. Then, a sensitive analytical method for flavonoids with ideal linear range (1–500 ng mL−1), low detection limit (0.15–0.41 ng mL−1) and good repeatability (2.64–6.20%) was developed under optimized conditions. In addition, the [email protected] hybrid sorbent has better selectivity for hydrophobic targets containing multiple hydrogen bond acceptors/donors. Finally, the established method was applied to the determination of flavonoids in different food samples, and satisfactory recoveries (81.4–102.1%) were obtained, which initially confirmed its applicability.

Schiff-base reaction

Solid-phase extraction

Synergistic effect

Flavonoids

Data will be made available on request.

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