单波长激发-能量色散X射线荧光光谱法检测蔬菜中多种重金属元素  

Determination of Heavy Metals in Vegetables by Single Wavelength Excitation-Energy Dispersive X-ray Fluorescence Spectrometry

作　　者：石洪玮 刘晓静 刘贵巧[1] 徐东辉[4] 毛雪飞[2] SHI Hongwei;LIU Xiaojing;LIU Guiqiao;XU Donghui;MAO Xuefei(Hebei University of Engineering,Handan,Hebei 056038,China;Institute of Quality Standard and Testing Technology for Agro-products,Chinese Academy of Agricultural Sciences,Supervision and Inspection Center for Quality and Safety of Agro-products,Ministry of Agriculture and Rural Affairs,Beijing 100081,China;Beijing Anke Huisheng Technology Co.,Ltd.,Beijing 101102,China;Institute of Vegetables and Flowers,Chinese Academy of Agricultural Sciences,Key Laboratory of Vegetables Quality and Safety Control,Ministry of Agriculture and Rural Affairs,Beijing 100081,China)

机构地区：[1]河北工程大学,河北邯郸056038 [2]中国农业科学院农业质量标准与检测技术研究所/农业农村部农产品质量安全监督检验测试中心,北京100081 [3]北京安科慧生科技有限公司,北京101102 [4]中国农业科学院蔬菜花卉研究所/农业农村部蔬菜质量安全控制重点实验室,北京100081

出　　处：《中国无机分析化学》2022年第4期1-8,共8页Chinese Journal of Inorganic Analytical Chemistry

基　　金：海南省重点研发计划项目(ZDYF2021XDNY185);国家自然科学基金面上项目(32072307);中国农业科学院重大科研任务(CAAS-ZDRW202011)。

摘　　要：为实现蔬菜中多种元素的快速检测,利用单波长激发-能量色散X射线荧光光谱仪(MW-EDXRF),建立了蔬菜中As、Pb、Cd、Cr、Ni、Cu、Zn、Rb、Mn等元素的快速检测方法。对XRF的激发时间、载样量、样品压片等条件进行了优化,结果显示当累积激发时间达到600 s、载样量为2 g、样品压片15 MPa保持60 s时,可以实现XRF最优检测性能。在最优条件下,As、Pb、Cd、Cr、Ni、Cu、Zn、Rb、Mn的检出限(LOD)分别为0.07、0.07、0.07、0.32、0.32、1.2、0.4、0.08、0.3 mg/kg;对菠菜、葱、胡萝卜、豆角、番茄、姜、空心菜、莲藕、芹菜、蒜等蔬菜样品多次测定的相对标准偏差(RSD)在0.20%~10.0%,表明方法具有良好的精密度;测定5种蔬菜基体标准物质的加标回收率在80.0%~119%,与微波消解电感耦合等离子体质谱法(ICP-MS)测定结果对比的线性回归系数(R^(2))>0.99(Cu的R^(2)=0.9838),表明方法具有良好的检测准确度。同时,该仪器仅有不到10 kg,不需要样品消解处理,检测时间在10 min左右,非常适合蔬菜多种重金属的现场快速筛查。In this work,to fulfill the rapid detection of multi-elements in vegetable samples,a rapid detection method for As,Pb,Cd,Cr,Ni,Cu,Zn,Rb,Mn in vegetables was established using a monochromatic wavelength excitation-energy dispersion X-ray fluorescence spectrometer(MW-EDXRF).Herein,the excitation time,sample size,and sample tabletting conditions were optimized for the MW-EDXRF.Under the optimal conditions(total 600 s excitation and 15 MPa tabletting with 60 s for 2 g powered vegetable sample)the detection limits(LODs)of As,Pb,Cd,Cr,Ni,Cu,Zn,Rb and Mn were 0.07,0.07,0.07,0.32,0.32,1.2,0.4,0.08,0.3 mg/kg,respectively;the relative standard deviations(RSDs)of spinach,onion,carrot,bean,tomato,ginger,water spinach,lotus root,celery and garlic samples were in the range of 0.20%—10.0%,indicating good analysis precision.The recoveries of multi-elements in 5 vegetable certified reference materials(CRMs)ranged from 80.0%to 119%;the linear regression coefficients(R^(2))between multi-elements measured by this proposed method and microwave digestion inductively coupled plasma mass spectrometry(ICP-MS)were greater than 0.99 except(R^(2)=0.9838 for Cu),indicating a favorable detection accuracy.As well,the instrumental weight is less than 10 kg,and the analysis time is~10 min without sample digestion process,which is very suitable for the rapid and field screening analysis for multi-elements including key heavy metals in vegetables.

关 键 词：X射线荧光光谱法 单波长激发 蔬菜 重金属 多元素同测 

分 类 号：O657.34[理学—分析化学] TH744.15[理学—化学]