材料期刊网

建立了牛奶中头孢洛宁残留检测的高效液相色谱-串联质谱方法。1g 牛奶经乙腈沉淀蛋白质后，上清液于37℃水浴下氮气吹干，用1 mL甲醇-0.1％甲酸水溶液（3：7，v/v）复溶，正己烷除脂净化后检测。流动相为乙腈和0.1％甲酸水溶液，梯度洗脱，经 C18色谱柱分离，采用多反应监测正离子模式对头孢洛宁进行定性定量分析。采用基质匹配法对牛奶中头孢洛宁的含量进行标准校正，在2~200μg/L范围内，头孢洛宁质量浓度与其对应峰面积的线性关系良好，相关系数﹥0.999。牛奶中加标样品的检出限（按S/N≥3计）为0.5μg/kg，定量限（ S/N≥10计）为2μg/kg。在定量限、1/2最高残留限量、最高残留限量、2倍最高残留限量添加水平下，牛奶中头孢洛宁的平均回收率为78.5％~86.2％，日内相对标准偏差为1.5％~6.2％，日间相对标准偏差为2.9％~5.6％。该方法可用于牛奶中头孢洛宁的残留检测。

An analytical method was developed for the determination of cefalonium in milk by high performance liquid chromatography-tandem mass spectrometry( HPLC-MS/MS). A total of 1g milk was deproteinized by acetonitrile. The supernatant was transferred into a test tube to be blown dry with N2 at 37 ℃.Then the residue was dissolved with methanol-0.1% formic acid in water(3:7,v/v). The sample was determined by HPLC-MS/MS after the purification.The chromatographic separation was achieved on a C18 column using 0.1% formic acid in water and acetonitrile as mobile phases with gradient elution. Qualitative and quantitative analyses were achieved by HPLC-MS/MS under positive ionization and multiple reaction monitoring( MRM ) mode.Matrix-matched calibration curve was used for the quantification. Good correlation coef-ficients were obtained( r﹥0. 999)in the mass concentration range of 2-200 μg/L. The limit of detection( LOD,S/N≥3)was 0. 5 μg/kg in milk,and the limit of quantification( LOQ,S/N≥10)was 2 μg/kg. The mean recoveries at the four levels of LOQ,1/2MRL( maximum residue level),MRL,2MRL were between 78. 5% and 86. 2%,with the intra-day relative standard devi-ations( RSDs)of 1. 5% to 6. 2% and inter-day RSDs of 2. 9% to 5. 6%. In conclusion,the estab-lished method can be applied for the determination of cefalonium residue in milk.