ICP-MS法测定陕西不同产地野生茜草中9种重金属元素

目的测定并分析陕西不同产地野生茜草中重金属元素,对其安全性进行评价。方法从陕西省7个主要野生茜草产区收集了35份茜草药材样品,采用微波消解-电感耦合等离子体质谱(ICP-MS)法测定样品中铜(Cu)、锰(Mn)、铬(Cr)、锌(Zn)、镉(Cd)、铁(Fe)、铅(Pb)、汞(Hg)、砷(As)9种重金属元素的含量,统计分析不同产地样品中重金属元素含量的差异。同时,采用主成分分析对所有样本进行聚类以及皮尔逊相关性系数分析,阐明9种重金属元素之间的相关性。结果陕西省不同产地野生茜草药材中重金属元素的含量存在差异性,Cu、Cd、Pb、Hg、As含量均低于重金属限量标准。主成分分析可将所有样品按关中、陕北和陕南归为3类,不同重金属元素之间存在一定的相关性。结论 ICP-MS方法可准确测定陕西野生茜草中重金属元素的含量,不同产地间存在差异。以重金属元素为指标,陕西产茜草是安全的。

Determination of nine heavy metals in Rubia Radix et Rhizoma from different habitats of Shaanxi province by ICP-MS

Objective To determine the contents of nine heavy metals in Rubia Radix et Rhizoma from Shaanxi province and to evaluate its safety. Methods Microwave digestion method used in sample pretreatment combined with an inductively coupled plasma mass spectrometric (ICP-MS) method were applied to determine the contents of nine heavy metals, i.e. Cu, Mn, Cr, Zn, Cd, Fe, Pb, Hg, and As in 35 samples of Rubia Radix et Rhizoma from seven wild populations in Shaannxi Province. The differences of heavy metals contents in different habitats were compared by statistical analysis. Principal component analysis (PCA) was performed to obtain an overview of the distribution of all samples and Pearson correlation analysis was used to determine the particular relationships among the levels of the nine heavy metals. Results The content of each heavy metal in the 35 samples of Rubia Radix et Rhizoma was below the detection limit and the contents of the nine heavy metals existed variation among the seven districts. Scores plot clearly separated the 35 samples into three groups (Guanzhong, Shaannan, and Shaanbei) by PCA. Pearson correlation analytical results demonstrated strong correlations among different heavy metals. Conclusion The developed ICP-MS method is suitable to accurately quantify the content of heavy metals in the samples of Rubia Radix et Rhizoma. Although the content of those varies in different habitats, Rubia Radix et Rhizoma is considered safe on the basis of the level of heavy metals.