海参铅同位素测定及产地溯源研究

Study on lead isotopic determination and origin traceability of sea cucumber

目的 基于铅同位素实现对海参的产地溯源。方法 海参样品经冷冻干燥、粉碎、微波消解后,利用电感耦合等离子体-质谱法(inductively coupled plasma-mass spectrometry,ICP-MS)对海参铅同位素进行测定,对数据进行差异性分析,结合主成分分析和判别分析建立锦州、烟台、霞浦3个产区底播海参的判别模型。结果 调整样品消解液中总铅含量在5~20μg/L,采用10μg/L的标准溶液进行交叉测量,可对质量歧视效应进行准确修正;204Pb/^(206)Pb、^(207)Pb/^(206)Pb和^(208)Pb/^(206)Pb的日内精密度分别为0.02%、0.02%和0.01%,日间精密度分别为0.04%、0.02%和0.01%。用此方法对生物成分分析标准物质大虾和扇贝的铅同位素进行测定,^(207)Pb/^(206)Pb和^(208)Pb/^(206)Pb的相对标准偏差小于0.1%,204Pb/^(206)Pb的相对标准偏差小于0.3%。应用此方法对取自锦州、烟台、霞浦3个海参主产区的底播海参进行铅同位素测定,结合主成分分析和判别分析,实现了有效区分,判别正确率在90.0%以上。结论 采用本方法建立的铅同位素比值测定技术可以实现海参的产地溯源。

Objective To realize the origin traceability of sea cucumber based on lead isotopes.Methods After freeze-dried,pulverized,and microwave digested,the lead isotopes in sea cucumber samples were determinated by inductively coupled plasma-mass spectrometry(ICP-MS),the data were subjected to differential analysis,and a discriminant model was established for bottom seeding sea cucumbers by combining principal component analysis and discriminant analysis among the 3 production areas:Jinzhou,Yantai and Xiapu.Results The 10μg/L standard solution for cross measurement could correct the quality discrimination effect accurately when the total lead concentration between 5‒20μg/L in the sample solution.The intra day precisions were 0.02%,0.02%,and 0.01%for 204Pb/^(206)Pb,^(207)Pb/^(206)Pb,and ^(208)Pb/^(206)Pb,respectively,and the inter day precisions were 0.04%,0.02%,and 0.01%,respectively.The lead isotope ratios of raw shrimp and scallop biocomponent analysis standard materials were determined according to the established method,the relative standard deviations of ^(207)Pb/^(206)Pb and ^(208)Pb/^(206)Pb were below 0.1%,and the relative standard deviation of 204Pb/^(206)Pb was below 0.3%.This method was applied to determine lead isotopes in bottom seeded sea cucumbers from 3 main production areas of sea cucumbers,Jinzhou,Yantai and Xiapu,after principal component analysis and discriminant analysis,effective discrimination was achieved with a discriminant correct rate above 90.0%.Conclusion The lead isotope ratio determination technique established by this method can be used to trace the origin of sea cucumber.