Abstract: The method for the simultaneous determination of 33 quinolone （QN） and sulfonamide （SA） residues in eels and shrimps was developed by high performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS). The deuterium substituted reagents which were used as internal standards were added to the sample before the extraction. The sample was extracted with acidified acetonitrile, cleaned-up by hexane, and concentrated with a rotary evaporator. The mass spectrometer was operated in the positive ion mode using selected reaction monitoring for the qualitative and quantitative analysis of 33 SAs and QNs at the same time. The limits of detection for 33 SAs and QNs were 1.0 μg/kg (S/N=3), and the limits of quantification were 2.0 μg/kg (S/N=10). The correlation coefficients of linear calibration curves were over 0.99 in the concentration range of 10.0-200.0 μg/L. The average recoveries for 33 SAs and QNs were between 66% and 123%. The advantages of the method are simple operation and low cost. The method realized fast routine analysis.

Key words: deuterium substituted reagents, eels, internal standard method, multi-residues, quinolones, shrimps , sulfonamides, high performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS)