固相萃取净化-微波辅助衍生-气相色谱-质谱法测定番茄酱中灭蝇胺及其代谢物三聚氰胺

Determination of Cyromazine and its Metabolite Melamine in Ketchup by Solid-Phase Extraction (SPE)Cleaned up-Microwave-Assisted Derivatization-Gas Chromatography-Mass Spectrometry

[目的]建立了固相萃取净化-微波辅助衍生-气相色谱-质谱法测定番茄酱中灭蝇胺和三聚氰胺含量的分析方法。[方法]样品经乙酸-乙腈-水溶液超声提取,离心,滤液经混合型阳离子交换固相萃取柱净化,氮气吹干,微波辅助硅烷化衍生,气相色谱-质谱测定,选择离子监测模式,基质匹配外标法定量。[结果]在0.01～5mg/kg的范围内线性良好（r〉0.99）,在0.25～1.0mg/kg的添加水平范围内,灭蝇胺和三聚氰胺的平均回收率分别为98%～109%和84%～94%,相对标准偏差（RSD）分别为5.7%～8.5%和3.2%～7.4%,灭蝇胺和三聚氰胺的检出限（LOD）分别为0.02mg/kg和0.01mg/kg。[结论]该方法简便、快速、灵敏、准确、低成本、耐用,适合番茄酱中灭蝇胺和三聚氰胺确证和定量测定。

A solid-phase extraction（SPE） cleaned up/microwave-assisted derivatization/gas chromatography-mass spectrometry method is presented for the quantitative determination and confirmation of cyromazine and its metabolite melamine in ketchup.The ketchup sample was extracted with acetic acid-acetonitrile water solution.An aliquot of the filtrate was cleaned up using mixed-mode cation exchange solid-phase extraction（SPE） cartridges,evaporated to dryness under nitrogen gas and the residue was converted to trimethylsilyl derivatives by microwave-assisted,and then the derivatives were analyzed by gas chromatography-mass spectrometry in selected ion monitoring（SIM） mode and matrix-matched external standards calibration curves were used for quantitative determination.The linear range was from 0.01 to 5mg/kg.The average recoveries were 98%-109% for cyromazine and 84%-94% for melamine and relative standard deviations were 5.7%-8.5% for cyromazine and 3.2%-7.4% for melamine in the spiked range of 0.25-1.0mg/kg.The limits of detection were 0.02mg/kg and 0.01mg/kg for cyromazine and melamine respectively.The method was simple,rapid,sensitive,accurate,and inexpensive and it is suitable for the quantitative determination and confirmation of cyromazine and its metabolite melamine residues in ketchup.