微波消解-电感耦合等离子体质谱(ICP-MS)法准确测定茶叶中总硒含量  

Determination of Selenium in Tea by Microwave Digestion-inductively Coupled Plasma Mass Spectrometry(ICP-MS)

作　　者：许文琪 XU Wenqi(China National Quality Supervision and Testing Center for Processed Food(Fuzhou),Fujian Inspection and Research Institute for Product Quality,Fuzhou 350002,China)

机构地区：[1]国家加工食品质量监督检验中心(福州),福建省产品质量检验研究院,福建福州350002

出　　处：《茶叶科学》2024年第6期1014-1022,共9页Journal of Tea Science

基　　金：福建省产品质量检验研究院科技项目(闽检科〔2023〕9号KY202219A)。

摘　　要：为了提高微波消解-ICP-MS法的灵敏度和稳定性,建立了一套准确检测茶叶中硒含量的方法,检测了甲醇、乙醇、异丙醇、正丁醇等作为增敏剂的增敏效果以及0~10%正丁醇添加入内标对准确测定茶叶中总硒含量的影响。结果表明,以3%正丁醇作为增敏剂,茶叶标准物质的总硒含量的检出限更低(0.00171 mg·kg^(-1)),检测结果准确度更高。该方法在0~50.0μg·L^(-1)范围内具有良好的线性关系(R^(2)>0.999);加标回收率为86.0%~104.0%;相对标准偏差为1.10%~4.44%。采用该方法与原子荧光光谱法分别对市售的7款富硒茶叶中的总硒含量进行测定,并对同一样本的两个检测数值进行配对t-检验,结果显示两种方法的检测结果无显著差异(P>0.05)。该方法操作简单、灵敏度高、检出限更低,精密度更高,且具有较好的重现性,更适用于茶叶中总硒含量的准确测定。In order to improve the sensitivity and stability of microwave digestion-inductively coupled plasma mass spectrometry(ICP-MS),an accurate method for the determination of selenium in tea was established.The sensitization effects of methanol,ethanol,isopropanol,n-butanol etc.as sensitizers were investigated,as well as the impact of adding 0-10%n-butanol to the internal standard on the accurate determination of total selenium content in tea were tested.By optimizing the pretreatment method and ICP-MS instrument parameters,a method for the accurate detection of total selenium content in tea using microwave digestion-ICP-MS with 3%n-butanol as the sensitizer was established.This method enhances the selenium signal intensity,thereby improving the accuracy and stability of the total selenium content detection in tea.To determine the optimum conditions for the determination of total selenium in tea,n-Butanol as sensitizer had lower detection limit and higher accuracy(0.00171 mg·kg^(-1)),and 3%n-butanol had the best sensitizing effect.It was more accurate to determine the selenium content in tea reference materials.The linear correlation coefficient R^(2)of selenium curve was greater than 0.999.The recovery of the added standard was from 86.0%to 104%,and the relative standard deviations(RSD)was between 1.10%and 4.44%.The paired t-test shows that the P value was greater than 0.05,and there was no significant difference between the two atomic fluorescence spectroscopy.This method is simple,showing high sensitivity,low detection limit,high precision and good reproducibility.This method is suitable for the accurate determination of selenium in tea.

关 键 词：微波消解 电感耦合等离子-质谱 正丁醇 茶叶 硒 

分 类 号：S571.1[农业科学—茶叶生产加工] S482[农业科学—作物学]