摘要
建立一种通过硝酸-微波消解-电感耦合等离子质谱法(ICP-MS)测定茶叶中硒含量的方法。通过对4种酸体系、4种消解方式比较样品前处理效果,确定消解方法为微波消解法,消解液为质量分数65%硝酸(7.0 mL)溶液。通过对仪器条件优化,确定测定模式为KED模式,在线加入内标溶液(^(73)Ge),分析同位素为^(78)Se。结果表明:建立的方程在质量浓度0.5~50.0μg/L范围内线性关系良好,相关系数为0.9995,方法的检出限为0.008 mg/kg,低、中、高3个加标水平的平均回收率分别为83.36%、83.43%、84.24%。对市售富硒茶叶样品进行分析,相对标准偏差(n=6)为3.6%。建立的方法准确度和灵敏度高、精密度好,适用于茶叶中微量硒的测定。
A method for the determination of selenium in tea by nitric acid-microwave digestion and inductively coupled plasma-mass spectrometry(ICP-MS)was established.By comparing the sample pretreatment effect of 4 kinds of acid systems and 4 kinds of digestion methods,it was determined that the digestion method was microwave digestion method,and the digestion solution was 65% nitric acid(7.0 mL)solution.By optimizing the instrument conditions,it was determined that the determination mode was KED mode,the intemal standard solution(^(73)Ce)was added online,and the isotopic analysis was^(78)Se.The results showed that the linear relationship of the established equation was good in the range of mass concentration 0.5-50.0μg/L,and the correlation coefficient was 0.9995.The detection limit of the method was 0.008 mg/kg,and the average recoveries of low,middle and high levels were 83.36%,83.43% and 84.24%,respectively.The relative standard deviation(n=6)of selenium-rich tea samples was 3.6%.The method has high accuracy,sensitivity and precision,and is suitable for the determination of trace selenium in tea.
作者
杨方方
梁鹏云
刘常凯
昝川南
YANG Fang-fang;LIANG Peng-yun;LIU Chang-kai;ZAN Chuan-nan(Guangxi-ASEAN Food Inspection and Testing Center,Nanning 530021,Guangxi,China;Nanning Houxin Biotechnology Co.,Ltd.,Nanning 530009,Guangxi,China)
出处
《粮食与油脂》
北大核心
2024年第4期153-157,共5页
Cereals & Oils
基金
广西壮族自治区市场监督管理局科技计划项目(GXSJKJ2021-2)
广西-东盟食品检验检测中心自立课题(KY202003)。
关键词
茶叶
电感耦合等离子体质谱法
硒
tea
inductively coupled plasma-mass spectrometry
selenium
