高效液相色谱-串联质谱法测定豆制品中3种甲基咪唑类化合物

Simultaneous determination of 3 methylimidazoles in bean product by high performance liquid chromatography-tandem mass spectrometry

目的建立豆制品中同时测定4-甲基咪唑、N-甲基咪唑及2-甲基咪唑的高效液相色谱-串联质谱(HPLCMS/MS)方法。方法样品采用水提取,强阳离子交换固相萃取柱富集净化,用HILIC色谱柱以乙腈-5 mmol/L乙酸铵溶液(9+1,V/V)为流动相进行分离,在串联质谱的电喷雾正离子多反应监测模式(MRM)下测定,内标法定量。结果在优化的实验条件下,3种化合物在20 ng/ml^400 ng/ml时线性关系良好,相关系数大于0.994,方法的测定低限为10μg/kg,平均回收率为92.0%~110.1%,RSD为2.9%~8.3%。利用本法对市售豆制品中的甲基咪唑类化合物进行检测,4-甲基咪唑检出率为84%,N-甲基咪唑检出率为7%,2-甲基咪唑检出率为1%。结论本方法灵敏、快速、准确,适用于豆制品中4-甲基咪唑、N-甲基咪唑及2-甲基咪唑的检测。

Objective To develop a method for simultaneous determination of 4-methylimidazole,2-methylimidazole and1-methylimidazole in bean product by high performance liquid chromatography-tandem mass spectrometry（ HPLC-MS/MS）.Methods The target chemicals in samples were extracted with water and purified with solid phase extraction cartridge（ SPE）,and then separated on a HILIC column with acetonitrile and 5 mmol/L ammonium acetate aqueous solution（ 9∶1,V/V） as mobile phase,detected under multiple reactions monitoring（ MRM） mode via positive electrospray ionization（ ESI＋） and quantified based on internal standard method. Results Under the optimized condition,good linearity was obtained in the range of 20 ng/ml-400 ng/ml,with correlation coefficients greater than 0. 994. The limits of quantitation（ LOQ） of the method was 10 μg/kg. The recoveries were in the range of 92. 0%-110. 1%,with RSDs of 2. 9%-8. 3%. This method was applied to market bean products,the detection rate of 4-methylimidazole,1-methylimidazole and 2-methylimidazole were respectively 84%,7%,1%.Conclusion The method is sensitive,accurate and reliable,and suitable for the determination of 4-methylimidazole,2-methylimidazole and 1-methylimidazole in bean product.