Dispersive magnetic solid-phase extraction based on triazine-conjugated microporous polymers for rapid and sensitive analysis of pyrrolizidine alkaloids and their N-Oxides in Honey.

A series of magnetic conjugated microporous polymers (Fe3O4CMPs) were synthesized and evaluated for the dispersive magnetic solid-phase extraction (DMSPE) of 17 Pyrrolizidine alkaloids (PAs) and their N-oxides (PANOs) in honey. Among them, Fe3O4CMP-TEPT, which contains triazine structure, demonstrated the highest effectiveness and was selected and combined with UHPLC-MS/MS for the determination of the target analytes. Extraction parameters were systematically optimized via single-factor and Box-Behnken design experiments. The adsorption mechanism was further explored through density functional theory calculations and adsorption experiments. The developed method exhibited excellent linearity (R² ≥ 0.99) in the ranges of 1-200 μg·L-1 (for two analytes), 2-200 μg·L-1 (for ten analytes), 3-200 μg·L-1 (for three analytes) and 5-200 μg·L-1 (for two analytes). Spike recovery experiments in blank honey at levels of 5-100 µg·kg-1 showed recoveries of 74.4%-118.7% with relative standard deviations below 10%. The limits of quantification (LOQs) ranged in 0.9-3.5 μg·kg-1. The method was successfully applied to detect honey samples from market in China, revealing trace levels of PAs/PANOs (1.6-17.3 μg·kg-1). The Fe3O4CMP-TEPT-based DMSPE-UHPLC-MS/MS method proved to be a rapid, sensitive, and reliable platform for monitoring PAs/PANOs contaminants in food commodities.