微波消解-ICP-MS法快速分析藏药“佐塔”中的金属元素

Analysis of metallic elements in"Zogta"with microwave digestion and inductively coupled plasma mass spectrometry(ICP-MS)

目的:建立电感耦合等离子体质谱(ICP-MS)法检测藏药"佐塔"中汞(Hg)、钙(Ca)、钾(K)、铁(Fe)、铜(Cu)、锌(Zn)、铅(Pb)7种金属元素的含量。方法:样品经微波消解,以^(209)Bi、^(45)Sc、^(72)Ge为在线内标,调节仪器测定参数,确定仪器最佳工作条件;根据半定量分析结果,配制各元素系列标准溶液,将试剂空白、标准系列、样品溶液分别引入仪器,同时测定;用方法精密度试验和加样回收率试验验证方法的精密度、准确度。结果:测定元素的工作曲线,线性相关系数均在0.999以上,测定方法RSD均小于5.0%(n=6),各元素的平均加样回收率为94.7%～103.4%。结论:ICP-MS法检出限低,简便快速,准确可靠。测定结果表明,不同产地的"佐塔"样品中,Hg、Ca、K、Fe、Pb的含量较高,但差别较大,应进一步规范配制工艺,加强质量监控,以保证其疗效稳定可靠。

Objective：To establish an ICP - MS method for the determination of metallic elements,including Hg, Ca, K, Fe, Cu,Zn and Pb in Tibetan medicine ＂Zogta＂. Method ：The sample was digested with microwave digestion system,and the contents of 7 metallic elements were analyzed by ICP - MS. Serial mixed standard solutions were prepared by 5% HNO3. The concentrations of Hg was 0,20,50,100,200,500 μg · L^-1 ;Ca,Pb were 0,5,10,20, 50,100 μg · L^-1;K,Fe were 0,10,20,50,100,200μg · L^-1;and Cu,Zn were 0,1,2,5,10,20μg · L^-1,respectively. ^209Bi ,^45Sc and ^72Ge were selected as on -line internal standard elements and the instrument parameters were adjusted to good state. The accuracy and precision of the method were validated by measuring the relative standard deviations （RSDs） and recoveries of the measured metallic elements. Results： The linear correlative coefficients for 7 metallic elements was higher than 0. 999,with the RSDs 〈 5.0% （n = 6） , and the average recoveries ranged from 94. 7% to 103.4%. Conclusion： This method is convenient, rapid, accurate and highly sensitive. Meanwhile, the contents of the Hg, Ca, K and Fe, are significantly different in two kinds of ＂Zogta＂, so syndicated quality standard system should be studied and established that safety and efficacy of the different products of ＂Zogta＂ can be ensured.