微波消解—电感耦合等离子体质谱法同时测定莲藕中15种元素

Simultaneous determination of 15 elements in lotus root by inductively coupled plasma mass spectrometry with microwave digestion

目的建立微波消解-电感耦合等离子体质谱法同时测定莲藕中锂(Li)、铝(Al)、钒(V)、铬(Cr)、锰(Mn)、镍(Ni)、铜(Cu)、砷(As)、硒(Se)、镉(Cd)、锡(Sn)、锑(Sb)、钡(Ba)、汞(Hg)和铅(Pb)的分析方法。方法莲藕经HNO3-H2O2体系微波消解后,电感耦合等离子体质谱仪测定15种元素的含量,在线内标校正干扰。结果 15种元素的线性相关系数均>0.999 1,检出限为0.000 2~0.490mg/kg,加标回收率为90.72%~107.71%,相对标准偏差RSD为1.49%~4.59%;苹果标准物质测定结果符合证书要求。应用该方法测定湖北省2018年秋季市售莲藕中上述15种元素的含量,铝、锰、镍、铜和钡检出率为100.00%,锑和汞低于检出限;按照GB 2762-2017《食品中污染物限量》对其含量进行评价,所检测的元素含量均未超过国家标准。结论该方法检出限低、精密度高、准确度好,可用于莲藕中15种元素的日常检测。

Objective To develop a detection method based on microwave digestion-inductively coupled plasma mass spectrometry(ICP-MS) for the determination of 15 elements including Li, Al,V,Cr,Mn,Ni,Cu,As,Se,Cd,Sn,Sb,Ba,Hg and Pb in lotus root. Methods The samples were decomposed by microwave digestion and detected by ICP-MS. The matrix effect was calibrated by internal standards. Results The linear correlation coefficients of the 15 elements were all greater than 0.999 1.The detection limits were in the range of 0.000 2-0.490 mg/kg, and the recovery rates were in the range of 90.72%-107.71%. The relative standard deviations were in the range of 1.49%-4.59%.The results of apple reference material were in accordance with the requirements of the certificate. This method was used to detect the content of the above mentioned 15 elements in lotus root sold in autumn of 2018 in Hubei Province. The detection rate of Al, Mn, Ni, Cu, and Ba was 100.00%,while Sb and Hg were below the detection limit. All the detected elements did not exceed the national standard. Conclusion The detection method developed in the present study has advantages of low detection limit, high precision and good accuracy, and can be used for the daily detection of the 15 elements in lotus root.