高效液相色谱-串联质谱法测定牛乳中 3 种糖肽类抗生素残留

建立牛乳中万古霉素、去甲万古霉素和替考拉宁的高效液相色谱-串联质谱测定方法。采用多反应监测模式，外标法定量。通过对不同提取溶剂的考察，选择0.1%甲酸水溶液-乙腈溶液（85∶15，V/V）作为提取溶剂；牛乳样品经超声辅助提取后，选用阳离子交换柱对万古霉素和去甲万古霉素进行净化，采用C18固相萃取柱对替考拉宁进行净化；流动相选择乙腈-0.1%甲酸水溶液体系，并采用梯度洗脱模式；分析物经反相C18色谱柱分离后，用质谱进行测定。结果表明：万古霉素、去甲万古霉素和替考拉宁的检出限分别为2、1、2 μg/kg，定量

Determination of Three Glycopeptide Antibiotics in Milk by High Performance Liquid Chromatography-Tandem Mass Spectrometry

A high performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS) method was developed for the determination of vancomycin, norvancomycin and teicoplanin in milk samples. Selective reaction monitoring was performed and the external standard method was used for quantification. Among various solvents tested, 0.1% formic acid-acetonitrile (85:15, V/V) was selected. Samples were ultrasonically extracted and vancomycin and norvancomycin were cleaned up by cation exchange column chromatography, while teicoplanin was purified using a C18 solid-phase extraction (SPE) cartridge. Acetonitrile-0.1% formic acid solution was chosen as mobile phase for gradient elution. The analytes were separated on a reversed-phase C18 column before being analyzed by mass spectrometry. The limits of detection (LOD) for vancomycin, norvancomycin and teicoplanin were 2, 1 and 2 μg/kg, and the limits of quantitation (LOQ) were 4, 2 and 4 μg/kg, respectively. The recoveries of the method ranged from 77.3% to 84.5% at spiked levels equal to LOQ, 5 × LOQ and 10 × LOQ, with relative standard deviations (RSD) of 4.7%–7.2%. The method could be used in the qualitative and quantitative detection of vancomycin, norvancomycin and teicoplanin in milk samples.