Simultaneous Determination of 21 Sulfonamide Residues in Aquatic Products by Ultra Performance Liquid Chromatography-Electrospray Ionization Tandem Mass Spectrometry

An ultra performance liquid chromatography-electrospray ionization tandem mass spectrometric (UPLC-MS/MS) method has been developed for the simultaneous determination of 21 sulfonamide residues in aquatic products. Samples were extracted with ethyl acetate, cleaned up using an HLB SPE cartridge and blown to dryness under nitrogen, and the residues were then dissolved in 1 mL of mobile phase. The 21 analytes were separated on ACQUITYTM BEH C18 column with a mobile phase composed of methanol and 5 mmol/L aqueous ammonium acetate solution (containing 0.1% formic acid). The limits for qualitative detection and quantitative determination were 0.01 -0.20μg/kg and 0.03 -0.67 μg/kg, respectively. The average recoveries at three spike levels ranged 68%-82%, with RSDs ranging 4.1%-11.8%. All these figures of merit demonstrate a good suitability of this method for the simultaneous determination of sulfonamide residues in aquatic products.