ICP-MS法比较蒲公英根与茎叶中人体必需微量元素的含量

摘要

建立了电感耦合等离子体质谱(ICP-MS)法同时快速、准确检测蒲公英根与茎叶中12种人体必需微量元素的分析方法,比较了蒲公英地上与地下部分中所含的Mn、Zn、Sr、Rb、B、Cu、Cr、Ni、V、Co、Se、Mo12种人体必需微量元素的含量,为评价其药用价值及其不同部位医疗保健成分的选择性开发提供理论依据.采用电热板湿法消解法,分别将蒲公英根、茎叶粉末(过200目筛)放入HNO3-H2O2(1:2,v/v)中进行消解,以ICP-MS法测定,以In、Rh元素为内标,标准曲线法计算各元素含量.结果,12种元素在0.05μg/L～150μg/L范围内线性关系良好,相关系数r均大于0.999,各元素的检出限为0.008μg/g～0.02μg/g,加样回收率为96.1％～103.8％.蒲公英地下及地上部分均富含这12种微量元素,其中,Mn、Sr、Rb、B等4种元素在茎叶中含量(120.70μg/g、92.88μg/g、30.69μg/g、32.67μg/g)均明显高于根中含量(81.72μg/g、36.10μg/g、20.14μg/g、14.19μg/g);Zn、Cu、Cr、Ni、V、Co、Se、Mo在根中含量(81.88μg/g、15.92μg/g、20.24μg/g、6.372μg/g、4.907μg/g、1.698μg/g、1.575μg/g、1.8μg/g)则高于茎叶中含量(70.5μg/g、12.47μg/g、8.142μg/g、5.801 μg/g、3.216μg/g、1.332μg/g、1.478μg/g、1.436μg/g).所建立的ICP-MS法具有良好的精密度、重复性和准确性,可用于同时测定蒲公英根、茎叶中12种人体必需微量元素的含量.蒲公英根与茎叶中微量元素含量有所不同,该结果为合理利用蒲公英不同部位提供了数据支持.%The ICP-MS method was established firstly for fast and accurate determination of essential trace elements contents in stem leaf and root of Taraxacum mongolicum.The comparison of the contents of trace elements Mn,Zn,Sr,Rb,B,Cu,Cr,Ni,V,Co,Se,Mo,existed in above-ground part and undergr-ound part of T.mongolicum was studied.This will provide theoretical basis for the medical value evaluation and the selective development of this pla-nts.Adopting the method of electric heating digestion,shoot and root powder (200mesh sieve) were digested respectively with the mixed volume ratio of 1:2 HNO3-H2O2 system,the contents of trace elements were determined by ICP-MS.In addition,In and Rh were regarded as internal standard,and the contents of trace elements were calculated by standard curve method.This method showed good linearity within the range from 0.05μg/L-150μg/L,he linear correlation coefficients (r) were greater than 0.999,the detection limit of each element were in the range of 0.008μg/g-0.02μg/g,and the reco-veries were between 96.1％ and 103.8％ respectively.Both of the shoot and root of T.mongolicum were rich in these 12 kinds of trace elements,including 4 kinds of elements Mn、Sr、Rb、B contents in stem leaf (120.70μg/g,92.88μg/g,30.69μg/g,32.67μg/g) were significantly higher than in root (81.72μg/g,36.10μg/g,20.14μg/g,14.19μg/g).Moreover,the contents of Zn、Cu、Cr、Ni、V、Co、Se、Mo in root (81.88μg/g,15.92μg/g,20.24μg/g,6.372μg/g,4.907μg/g,1.698μg/g,1.575μg/g,1.8μg/g) were higher than in shoot (70.5μg/g,12.47μg/g,8.142μg/g,5.801μg/g,3.216μg/g,1.332μg/g,1.478μg/g,1.436μg/g).The establis-hed method of ICP-MS was validated with good precision,repeatability and accuracy,which is appropriate for simultaneous determination of 12 kinds essential trace elements existed in stem leaf and root of T.mongolicum.The contents of trace elements in shoot and root were different,which will pro-vide data support for the rational use of different parts of T.mongolicum.