高效液相色谱-电感耦合等离子质谱法分析富硒茶叶中硒的形态

Speciation Analysis of Selenium in Selenium-Enriched Tea by HPLC-ICP-MS

建立富硒茶叶中硒代胱氨酸(Se Cys_2)、甲基-硒代半胱氨酸(Se MC)、亚硒酸根(Se(IV))、硒代蛋氨酸(Se Met)、硒酸根(Se(VI))5种硒化合物的高效液相色谱-电感耦合等离子体质谱的分离检测方法。方法利用Hamilton PRP-X100色谱柱对富硒茶叶中5种硒化合物进行分离,利用电感耦合等离子体质谱对硒元素进行检测,外标法定量测定5种硒化合物的含量。研究采用蛋白酶K溶液为提取剂,超声提取60 min,以柠檬酸溶液为流动相,梯度洗脱,5种硒化合物在15 min内得到了有效分离。5种硒化合物标准曲线的线性相关系数不小于0.999 8,检出限为0.13～1.09μg/L。该前处理方法样品加标回收率在91.8%～109.4%之间。方法操作简便、分离效果好、检出限低,适用于富硒茶叶中硒的形态分析。

A method for the determination of 5 selenium species(SeCys2,SeMC,Se(IV),SeMet,and Se(VI))in seleniumenriched tea was established using high performance liquid chromatography-inductively coupled plasma-mass spectrometry(HPLC-ICP-MS).A Hamilton PRP-X100 column was used to separate the five compounds using citric acid as the mobile phase.Quantification was performed by the external standard method.The five selenium compounds were ultrasonically extracted using 1 mL of protease K(10 mg/mL)for 60 minutes,and then separated with gradient elution in 15 min.The correlation coefficients of the standard curves were larger than 0.999 8,and the limits of detection(LODs)were in the range of 0.13–1.09μg/L.The spiked recoveries ranged from 91.8%to 109.4%.The method allowed simultaneous determination of selenium compounds in selenium-enriched tea with simple and convenient operation,efficient separation and low detection limit.