微波消解-石墨炉原子吸收法/原子荧光法测定食品中有害元素平台研究

Insight into the platform of analyzing harmful elements by microwave digestion-GFAAS/AFS

目的应用微波消解食品试样,建立用石墨炉原子吸收法(GFAAS)测定铅(Pb)、镉(Cd)、铬(Cr)、铝(Al),原子荧光法(AFS)测定汞(Hg)和砷(As)的测定平台。方法通过对样品微波消解条件的控制,使所得样液能同时用于GFAAS法测定Pb、Cd、Cr和Al,AFS法测定Hg和As。结果 Pb、Cd、Cr、Al、Hg、As的浓度为0μg/L^100μg/L时,线性关系良好,相关系数(r)为0.999 3~0.999 9,检出限分别为0.280μg/L、0.005μg/L、0.002μg/L、2.93μg/L、0.013μg/L、0.042μg/L。用菠菜标准物质(GBW10015)进行验证,Pb、Cd、Cr、Al、Hg、As的加标回收率为92.9%~109.0%,相对标准偏差(RSD)分别为3.87%、3.62%、4.15%、1.90%、5.74%、4.56%。结论该方法一次试样消解能分别测定食品中主要有害元素,方法简便、灵敏、准确,可满足基层食品安全风险监测工作中对有害元素检测的要求。

Objective Applying microwave digestion technology to digest food samples as well as establishing a testing platform with graphite furnace atomic absorption spectrometry（GFAAS） for the detection of lead（Pb）,cadmium（Cd）,chromium（Cr）,aluminum（Al） and with atomic fluorescence spectrometry（AFS） for the detection of mercury（Hg） and arsenic（As）.Methods By controlling the conditions of sample microwave digestion,the samples could be used for the detection of Pb,Cd,Cr,Al with GFAAS,and for the detection of Hg and As with AFS at the same time.Results Good linearity was obtained when the concentration of Pb,Cd,Cr,Al,Hg,As were in 0 μg/L-100 μg/L,with the correlation coefficient（r） in 0.999 3-0.999 9.The detection limits were respectively 0.280 μg/L,0.005 μg/L,0.002 μg/L,2.93 μg/L,0.013 μg/L,0.042 μg/L for Pb,Cd,Cr,Al,Hg and As.Being verified by using standard spinach components（GBW10015）,all the spiked recoveries were within 92.9%-109.0%,and the relative standard deviations（RSDs） were 3.87%,3.62%,4.15%,1.90%,5.74% and 4.56%,respectively.Conclusion This method is able to detect the main harmful elements in food by digesting the sample at a time.It is a simple,sensitive and accurate approach,which can meet the requirements of detecting harmful elements in food safety risk monitoring for basic laboratories.