摘要
采集了生长于青海省6个不同地区的枸杞样品150个,并制取分析用样品。每个样品称取约0.5g置于石英管中,加入水1mL和硝酸4mL,按程序进行微波消解,所得溶液在电感耦合等离子体质谱工作条件下测定其中24种微量元素(钾、钠、钙、镁、铁、锌、铜、锰、钴、镍、铅、砷、镉、铬、硒、钼、锑、锶、锡、镨、钆、镝、汞、铽)。用各元素的标准溶液绘制标准曲线。测得各元素的检出限(3s)在0.008~10μg·L-1之间。选用都兰地区的样品进行精密度和回收试验,24种元素测定值的相对标准偏差(n=6)在0.95%~6.6%之间。在回收试验中,称取4份样品,其中1份样品的测定值为本底值,其余3份样品中分别加入3个浓度水平的15种元素的标准溶液,按方法测得各元素的含量,计算得回收率在85.0%~107%之间。运用仪器自带的MPP软件对所有样品所测得的24种元素的分析数据进行主成分分析和聚类分析。结果表明:钠、镁、钙、锰、铁、钴、镍、铜、锌、镉、铅、钼、镨等元素含量在不同个体样品中差异较明显;来自德令哈与格尔木的样品区分度较好;都兰、乌兰和诺木洪的样品散布比较广,样品间的差异不明显;在青海省各地产出的枸杞的24种元素中,钆与镝存在高度相关。
150 samples of Lycium chinense grown in various areas in Qinghai Province were collected and the analytical samples were prepared.About 0.5 g of each of the samples was taken and dissolved in 1 mL of H2O and 4 mL of HNO3 by microwave digestion according to the prescribed programme.The solution obtained was used for determination of 24 trace elements(i.e.,K,Na,Ca,Mg,Fe,Zn,Cu,Mn,Co,Ni,Pb,As,Cd,Cr,Se,Mo,Sb,Sr,Sn,Pr,Gd,Dy,Hg and Tb)by ICP-MS.Standard curves were prepared by using standard solutions of the 24 elements.Detection limits(3 s)of these elements were found in the range of 0.008-10μg·L-1.Samples from Dulan area were used as matrixes in tests for precision and recovery.Values of RSDs(n=6)for the 24 elements were found in the range of 0.95% to 6.6%.Four portions of the sample were taken for recovery test.Values of the trace elements determined in one portion of the sample were taken as the base data,while standard solutions of 15 trace elements at 3 concentration levels were added separately to the other 3 portions of the sample,and the results obtained were used for calculation of values of recoveries,which were found in the range from 85.0% to 107%.Statistical study of the analytical data of the 24 trace elements by principal component analysis and clustering analysis was done by using the MPP soft ware which was attauched to the intrument.As shown by the results,significant differences of contents of Na,Mg,Ca,Mn,Fe,Co,Ni,Cu,Zn,Cd,Pb,Mo and Pr in various individual samples were observed;samples of Delingha area and Golmud area showed good differentiation;samples from Dulan,Wulan and Nomuhong were distributed in a wide area,their difference were not significant;and high correlation was found between Dy and Gd among the 24 trace elements of Lycium chinense grown in Qinghai Province.
作者
李莉
薛宾
魏玉海
LI Li;XUE Bin;WEI Yuhai(Technology Center of Xining Customs District of China,Xining 810016,China)
出处
《理化检验（化学分册）》
CAS
CSCD
北大核心
2019年第12期1431-1435,共5页
Physical Testing and Chemical Analysis(Part B:Chemical Analysis)
基金
海关总署科技计划项目(2017IK022)
青海省科技计划项目(2017-ZJ-762)
