超高效液相色谱-串联质谱法测定茶叶中高氯酸盐

Determination of perchlorate in tea by ultra performance liquid chromatography tandem mass spectrometry

目的建立一种使用同位素内标法定量测定茶叶中高氯酸盐的超高效液相色谱-串联质谱法(ultra performance liquid chromatography tandem mass spectrometry,UPLC-MS/MS)。方法茶叶样品经0.2%乙酸提取,高速离心,上清液用石墨炭黑柱净化,再经Thermo Acclaim TRINITY P1色谱柱分离,串联质谱法检测,内标法定量。结果高氯酸盐在0.25~50.0μg/L范围内线性关系良好,相关系数(r)为0.9991。加标浓度为0.05~0.80 mg/kg时,方法的平均回收率分别为在94.6%~110.2%,相对标准偏差为1.8%~9.6%。结论本方法前处理简单、灵敏度高、准确、可靠,适用于茶叶中高氯酸盐的测定。

Objective To establish a method for determination of perchlorate in tea by ultra performance liquid chromatography tandem mass spectrometry （UPLC-MS/MS） based on isotopic internal standard method. Methods The perchlorate residue in tea was extracted with 0.2% acetic acid, and then centrifuged. The supernatant was cleaned-up with Carb SPE. The separation ofperchlorate was carried out on a Thermo Acclaim TRINITY P1 column, and the detection was performed with tandem mass spectrometry with internal standard method for quantification. Results The calibration curve was linear in the concentration range of 0.25-50.0 μg/L （r=0.9991）. The average recoveries at the spiked levels of 0.05-0.80 mg/kg were 94.6%-110.2% and the relative standard deviations （RSDs） were 1.8%-9.6%, respectively. Conclusion This method is simple, sensitive, accurate and reliable, which is suitable for the determination ofperchlorate in tea.