Abstract: The polyclonal antibodies against gentamicin, kanamycin and apramycin were simultaneously coupled to CNBr-activated Sepharose 4B to make a composite immunoaffinity column (IAC). An ultra performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) method was developed for the simultaneous determination of the three aminoglycosides (AGs) in fish and shrimp with immunoaffinity column clean-up. The analytes were separated on a BEH Amide column（100 mm × 2.1 mm, 1.7 μm）utilizing gradient elution with a mixture of acetonitrile and 0.05% formic acid solution as the mobile phase. The analysis was carried out in the multiple reaction monitoring (MRM) mode using positive ion electrospray ionization (ESI). The column capacities of gentamicin, kanamycin and apramycin were 1 127, 1 368, and 925 ng/mL of gel, respectively. The optimum elution solvent was methanol containing 0.1% formic acid. The linear range of the method was 80.0–500 μg/L for gentamicin and 20–500 μg/L for kanamycin and apramycin, and the corresponding coefficients of correlation were all above 0.995. Recoveries from spiked fish and shrimp were in the range of 71.7%–96.8%, with relative standard deviations (RSDs) ranging from 4.2% to 10.9%. The limits of detection and the limits of quantitation were in the range of 10–40 and 20–80 μg/kg, respectively. The developed method would be a useful tool for monitoring aminoglycoside residues in aquatic products.

Key words: immunoaffinity column (IAC), ultra performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS), residue detection, aminoglycosides