Determination of Five Peptide Antibiotics in Pork by HPLC£­MS/MS Based on Pass-through Solid Phase Extraction

KeyWord:peptide antibiotics  liquid chromatography£­tandem mass spectrometry£¨HPLC£­MS/MS£©  pork  pass-through solid phase extraction

Abstract:

      A high performance liquid chromatography£­tandem mass spectrometric£¨HPLC£­MS/MS£© method was developed for the determination of five peptide antibiotics£¬i.e£®daptomycin£¬vancomycin£¬norvancomycin£¬virginiamycin M1 and virginiamycin S1 in pork based on a purification technique with non-activation pass-through solid phase extraction£¨SPE£© column£®The pork samples were extracted with methanol£­2% formic acid£¨5¡Ã2£¬by volume£©£¬and purified with a non-activation Captiva EMR£­Lipid SPE column£®The separation was carried out on a Phenomenex Kinetex F5£¨2.1 mm ¡Á 100 mm£¬2.6 ¦Ìm£© column by gradient elution£¬with 0.1% formic acid acetonitrile solution and 0.1% formic acid as mobile phases£®The target substances were analyzed in electrospray ion source positive ion mode under multi-reaction monitoring£¨MRM£© mode£¬and quantified by the internal standard method£®Results showed that the calibration curves of five peptide antibiotics in pork were linear£¨r2 > 0.99£© in the range of 2£­200 ng/mL for daptomycin£¬5£­500 ng/mL for vancomycin and norvancomycin£¬and 1£­100 ng/mL for virginiamycin M1 and virginiamycin S1£®The limits of detection were in the range of 3£­7.5 ¦Ìg/kg£¬and the limits of quantitation were in the range of 5£­25 ¦Ìg/kg£®The recoveries of five peptide antibiotics from negative pork samples at three spiked levels of 25£¬50£¬250 ¦Ìg/kg ranged from 80.2% to 102%£¬with intra-RSDs and inter-RSDs of 1.3%£­7.4% and 2.6%£­8.5%£¬respectively£®With the characteristics of simple pretreatment£¬good recovery and repeatability£¬this method based on Captiva EMR-lipid SPE column is suitable for the simultaneous analysis of 5 peptide antibiotics in pork.