液相色谱-质谱法测定乳及乳制品中氯霉素类抗生素的含量

Determination of chloramphenicols in milk and dairy products by liquid chromatography-mass spectrometry

中文关键词:  氯霉素  甲砜霉素  氟苯尼考  乳及乳制品  液相色谱-质谱法

英文关键词:chloramphenicol  thiamphenicol  florfenicol  milk and dairy products  liquid chromatography-mass spectrometry

中文摘要:

      目的 建立液相色谱-质谱法测定乳及乳制品中氯霉素类抗生素的残留量。方法 液态奶、酸奶、奶粉样本经乙酸乙酯提取, 经Waters Sep-pak C18固相萃取小柱净化, 至Agilent C18(150 mm×2.1 mm, 5 μm)色谱柱分离, 以乙腈:水(50:50, V:V)为流动相进行等度洗脱。质谱法采用电喷雾离子源负离子模式和多反应监测模式测定, 以内标法定量。结果 氯霉素、甲砜霉素、氟苯尼考3种待测物质在0.1~20 ng/mL范围内线性关系良好, 线性相关系数都在0.9995以上; 氯霉素的检出限为0.011~0.021 μg/kg, 甲砜霉素的检出限为0.042~0.100 μg/kg, 氟苯尼考的检出限为0.010~0.018 μg/kg; 氯霉素在0.05、0.5和1 μg/kg 3水平上的加标回收率为83.1%~95.6 %, 甲砜霉素在0.1、1和2 μg/kg 3水平上的的加标回收率为80.2%~102.1 %, 氟苯尼考在0.05、0.5和1 μg/kg 3水平上的的加标回收率为81.3 %~103.5%; 氯霉素的相对标准偏差为4.4%~6.4%, 甲砜霉素的相对标准偏差为4.1%~7.1%, 氟苯尼考的相对标准偏差为3.7%~6.6%。结论 本方法准确灵敏, 适用于乳及乳制品中氯霉素类抗生素残留量的测定。

英文摘要:

      Objective To establish a method for determination of chloramphenicols in milk and dairy products by high performance liquid chromatography- mass spectrometry (HPLC-MS). Methods The samples (liquid milk, yogurt and milk powder) were extracted by ethyl acetate, and purified by Waters Sep-pak C18 solid-phase extraction (SPE). The target compounds were separated by Agilent C18 (150 mm×2.1 mm, 5 μm) column with waters and acetonitrile (50:50, V:V) for gradient elution. The mass spectrometry was carried out by means of multiple reaction monitoring (MRM) in electrospray ionization (ESI) mode with internal standard for quantification. Results Chloramphenicol, thiamphenicol and florfenicol had good linear relationships in the range of 0.1~20 ng/mL with r>0.9995. The limits of detection of chloramphenicol, thiamphenicol and florfenicol were 0.011~0.021 μg/kg, 0.042~0.100 μg/kg and 0.010~0.018 μg/kg, respectively. The average recoveries of chloramphenicol spiked at 0.05, 0.5 and 1 μg/kg, thiamphenicol spiked at 0.1, 1 and 2 μg/kg and florfenicol spiked at 0.05, 0.5 and 1 μg/kg were 83.1%~95.6%, 80.2%~102.1% and 81.3 %~103.5%, with the relative standard deviations (RSDs) of 4.4%~6.4%, 4.1%~7.1% and 3.7%~6.6%, respectively. Conclusion The proposed method is accurate and sensitive, which can be used for the determination of chloramphenicol, thiamphenicol and florfenicol in milk and dairy products.