关键词: 差向物, 液相色谱-串联质谱法, 蜂蜜, 四环素类抗生素

Abstract: A method for simultaneous determination of 4 tetracyclines and 3 epimers in honey samples was developed by high performance liquid chromatography coupled with tandem mass spectrometry. The residues in honey samples were extracted by EDTA-Mcllvaine buffer, and cleaned up and condensed by OASIS hydrophilic-liphophilic balance (HLB) column and weak cation exchange (WCX and carboxylic acid) sequentially. Sample solution eluted from the WCX SPE column by mobile phase was filtered by micro-pours membrane, separated by LC-MS/MS with gradient elution using acetonitrile-formic acid solution as mobile phase and then qualitatively and quantitatively analyzed by ESI-MS/MS in a MRM mode. Baseline separation of 7 target drugs was achieved within 7 min, and qualitative and quantitative analysis was completed. The recovery rates of the spiked samples at trace levels were in the range of 64.9% to 91.0% with the relative standard deviation (RSD) less than 10.5% (n = 7). The detection limits were 1μg/kg for oxytetracycline, tetracyclines, 4-epitetracycline, 4-epioxytetracycline and 2μg/kg for chlortetracycline, doxycycline and epichlortetracycline. The developed method was sensitive and reliable, and can be successfully applied to the simultaneous detection of 7 target tetracyclines residues including toxic metabolites in honey.

Key words: high performance liquid chromatography-tandem mass spectrometry, honey, tetracyclines, epimers