Abstract: To address the difficulty of detecting aminoglycoside (AG) residues in the liver and kidney of livestock and poultry, the extraction solvent and purification method were improved. A rapid and accurate method for the determination of 12 AGs was developed using hydrophilic interaction chromatography-tandem mass spectrometry (HIC-MS/MS). This method employed phosphate buffer solution containing 50 g/L trichloroacetic acid and 50 g/L sodium chloride as the extraction solvent, which significantly improved the recovery of neomycin. After proper dilution, the extract was purified on a PRiME HLB solid phase extraction (SPE) column. Subsequently, the chromatographic separation was performed on an Obelisc R column using gradient elution with a mobile phase composed of acetonitrile and 1.0% formic acid in water (containing 1 mmol/L ammonium formate) before analysis by ultra-high performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS). The internal standard method was used for the quantitation of apramycin, hygromycin B, neomycin, and tobramycin, while the external standard method was adopted for the quantitation of the remaining eight compounds. The results revealed that the calibration curves for all analytes had good linearity within the corresponding concentration ranges, with determination coefficients of ≥ 0.99. The limits of detection (LOD) and quantitation (LOQ) ranged from 10 to 50 μg/kg and from 20 to 100 μg/kg, respectively. The recoveries for 8 blank liver and kidney matrices at low, medium, and high spiked levels were 78.0%–108.5%, with relative standard deviations (RSDs) ranging from 1.0% to 11.0% (n = 6). Using a single solid-phase extraction cartridge, the method developed herein is simple and easy to operate and can be used for accurate qualitative and quantitative analysis of AG residues in liver and kidney samples.

Key words: aminoglycosides; PRiME HLB solid phase extraction cartridge; liver; kidney; hydrophilic interaction chromatography-tandem mass spectrometry