超高效液相色谱-串联质谱法测定酱卤肉制品中1-甲基咪唑、2-甲基咪唑及4-甲基咪唑

Simultaneous Determination of 1-Methylimidazole,2-Methylimidazole and 4-Methylimidazole in Sauced Meat Products by Ultra High Performance Liquid Chromatograhpy-Tandem Mass Spectrometry

建立了酱卤肉制品中同时测定1-甲基咪唑(1-methylimidazole,1-MEI)、2-甲基咪唑(2-methylimidazole,2-MEI)和4-甲基咪唑(4-methylimidazole,4-MEI)的超高效液相色谱-串联质谱(UPLC-MS/MS)的分析方法。样品经水提取,强阳离子交换固相萃取柱(Waters Oasis MCX)富集净化,氮吹复溶后,Agilent Zorbax HILIC(2.1 mm×100 mm,3.5μm)色谱柱分离,以乙腈和5 mmol/L乙酸铵溶液为流动相梯度洗脱,采用电喷雾离子源正离子电离多反应监测模式(MRM)测定,同位素内标法定量。结果表明,1-MEI、2-MEI和4-MEI在30~400 ng/mL范围内,线性关系良好,相关系数均大于0.9997;方法检出限和定量限分别为10、30μg/kg;在30、60、300μg/kg加标水平下的平均回收率为92.0%~116.3%,相对标准偏差(n=6)为0.70%~3.96%。采用该方法对市售的36批次酱卤肉制品进行检测,1-MEI均未检出;2-MEI检出率为5.5%,含量为21.4~23.6μg/kg;4-MEI检出率为100%,含量为3.1~306.6μg/kg。该方法灵敏、快速、准确,适用于酱卤肉制品中1-MEI、2-MEI和4-MEI的定性定量测定。

An ultrahigh performance liquid chromatography-tandem mass spectorometric(HPLC-MS/MS)method was developed for the simultaneous determination of 1-methylimidazole(1-MEI),2-methylimidazole(2-MEI)and 4-methylimidazole(4-MEI)in sauced meat products.The sample was extracted with water and the extracting solution was cleaned by Waters Oasis MCX SPEcolumn.The eluantwas dried under a stream of nitrogen and dissolved with initial mobile phase,the analytes were then separated by the Agilent Zorbax HILIC(2.1 mm×100 mm,3.5μm)using binary mobile phase gradient with acetonitrile and 5 mmol/L ammonium acetate.The compounds were ionized by positive electrospay,then detected under the multiple reaction monitoring(MRM)mode and quantified by the isotope internal standard method.The linearity of 1-MEI,2-MEI and 4-MEI in the range from 30~400 ng/mL exhibited correlation coefficients greater than 0.9997.The limits of detection(LOD)and quantification(LOQ)were 10,30μg/kg.The average recoveries at three level spiked concentrations(30,60,300μg/kg)ranged from 92.0%to 116.3%,with the relative standard deviations(n=6)between 0.70%and 3.96%.The method was applied to detect 36 sauced meat products,the 1-MEI was not detected in sauced meat products;the detection rate of 2-MEI was 5.5%,the content was 21.4~23.6μg/kg,4-MEI was detected in all of samples,the content was 3.1~306.6μg/kg.The method was simple,rapid,sensitive and reliable,could be applied to determine1-MEI,2-MEI and 4-MEI in sauced meat products.