超高效液相色谱-串联质谱法检测保健食品中4-甲基咪唑含量

目的建立超高效液相色谱-串联质谱法测定保健食品中4-甲基咪唑含量的分析方法。方法样品采用90%乙腈水溶液超声提取后,提取液经过Waters BEH Hilic色谱柱,根据亲水作用色谱原理分离待测物,以0.1%甲酸乙腈-0.1%甲酸水溶液作为流动相洗脱,正离子电喷雾离子化,多反应监测模式检测,超高效液相色谱-串联质谱法(ultra performance liquid chromatography tandem mass spectrometry, UPLC-MS/MS)对样品进行分析。结果该方法用于4-甲基咪唑检测时,专属性、精密度和样品稳定性良好,线性范围在0.11～1.7ng/mL之间,相关系数r为0.9998;加标回收率在94.16%～116.1%之间,方法准确性良好;检出限为1 ng/g,定量限为3 ng/g,方法灵敏度较好。样品中检出4-甲基咪唑,含量在12.4～14.9 ng/g之间。结论该方法专属性强,准确性好,灵敏度高,适用于保健品中4-甲基咪唑的筛查和测定。

Determination of 4-methylimidazole in health food by ultra performance liquid chromatography tandem mass spectrometry

Objective To establish a method for determination of 4-methylimidazole in health food by ultra performance liquid chromatography tandem mass spectrometry (UPLC-MS/MS). Methods The samples were extracted by ultrasonic with 90% acetonitrile water solution. The extracting solution was separated by a Waters BEH Hilic column. According to hydrophilic interaction liquid chromatography theory, the target compound was eluted with 0.1% formic acid acetonitrile and 0.1% formic acid water solution as mobile phase. 4-methylimidazole was ionized by positive electrospray (ESI+), then detected with multiple reaction monitoring mode (MRM), and analyzed by UPLC-MS/MS. Results The specificity, precision and sample stability were satisfactory. The linearity range was 0.11?1.7 ng/mL, and the correlation coefficient was 0.9998. Recoveries were between 94.16% and 116.1%. The limit of detection was 1 ng/g, and limit of quantitation was 3 ng/g. 4-methylimidazole was detected in the testing samples, and the content was in the range of 12.4?14.9 ng/g. Conclusion This method is selective, accurate and sensitive, which is suitable for the screening and determination of 4-methylimidazole in health food