To establish an analytical method for the simultaneous determination of 15 kinds of quinolone residues in aquatic products by magnetic solid-phase extraction purification technology combined with ultra performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS).

Samples were extracted with acetonitrile-methanol (80:20, V:V) solution, and the extract was purified and enriched using Fe₃O₄@ZIF-8 core-shell structured magnetic nanomaterials. The mobile phase consisted of 0.2% formic acid water and methanol, with gradient elution, and analysis was performed under positive ion mode with electrospray ionization.

The 15 kinds of quinolones showed a good linear relationship within the range of 2.0–500.0 ng/mL, with correlation coefficients all greater than 0.998; the limits of detection were 0.05–0.28 μg/kg, and the limits of quantitation were 0.16–0.84 μg/kg. At 3 spiked levels, the average recovery ranged from 75.3% to 108.1%, with relative standard deviations of 1.1%–9.3%.

This method is simple, rapid and highly sensitive, and the magnetic materials used exhibit excellent adsorption performance and are reusable, conforming to green environmental protection principles. It has been successfully applied to the analysis and detection of quinolones in aquatic products such as grass carp, crucian carp, snakehead, loach, eel, bullfrog and geiwei shrimp.