茶叶中三甲基锍的HPLC-MS/MS检测方法和基质干扰消除作用

Application of high performance liquid chromatography tandem mass spectrometry to trimethylsulfonium determination in tea and its elimination of sample matrix

[目的]建立茶叶中三甲基锍的高效液相色谱-质谱联用(HPLC-MS/MS)检测方法,应用该方法检测市售茶叶中三甲基锍的含量。[方法]应用酸性乙酸铵和过氧化氢混合溶液加热提取茶叶中三甲基锍,所得样品提取液用N-丙基乙二胺净化,过膜后进样。再经亲水柱分离,采用多反应监测模式进行检测。基质匹配配制标准曲线,外标法定量。抽取市售茶叶45份,检测其三甲基锍的含量。[结果]目标化合物在0.032～1.00μg/L范围内线性关系良好,相关系数大于0.995。方法的定量限和检出限分别为10.0、4.00μg/kg。加标水平在10.0、20.0、40.0μg/kg时,样品的平均回收率为78.1%～127.0%,相对标准偏差为3.9%～10.4%。45份市售茶叶中有2份检出三甲基锍,分别为茉莉花茶32.9μg/kg和铁观音30.7μg/kg。[结论] HPLC-MS/MS法检测茶叶中的三甲基锍,可消除茶叶基质干扰,方法简便快速,精密度、准确性、检出限均能满足相关的技术规范的要求,并成功应用于市售茶叶中三甲基锍的检测。

[Objective]To apply high performance liquid chromatography tandem mass spectrometry （HPLC-MS/MS） to lhe qmmlitaliw-＇ determination of trimethvlsulfonium in retail tea products. [ Methods ] Trimethylsulfonium in lea product samples was extracted with heated mixed solution of acidic ammonium acelalc and hydrogen peroxide. The extraction was purified with primary secondary amine, injected after passing hydrophiliy membranes, and separated on hydrophilic column. The analyte was determined by HPI,C-MS/MS in multiple reaction monitoring （MRM） made and quantified by external matrix matched standard method. A total of 45 samples of retail tea products were detecled. [ Results ] The calibration cnrve showed good linearity in the range of O.032-1.00μg/L with a correlation coefficient grealer than 0.995. The limit of quantification （LOQ） and the limit of detection （LED） were 10.0 gg/kg and 4.00 gg/kg, respectively. The average recoveries varied from 78.1% to 127.0% with the relative standard deviations （RSDs） of 3.9%-10.4% at three spiked levels （10.0, 20.0, and 40.0,ag/kg）. Two samples were positive among the 45 samples, of which the trimethylsulfonium levels in jasmine tea and tieguanyin were 32.9 gg/kg and 30.7 μg/kg, respectively. [ Conclusion ] HPLC-MS/MS is a simple, accurate, and precise method to eliminate matrix in tea samples, with a limit of detevtion meeting relevant technical requirements; therefore, it is successfully applied to the determination nf trimethylsulfonium in retail tea products.