ICP-OES法测定坛紫菜中重金属元素

为探索一种坛紫菜Porphyra haitanensis重金属元素的快速检测的新方法，建立了电感耦合等离子体发射光谱（ICP-OES）方法测定坛紫菜中砷、镉、铬、汞、铅和锌等6种重金属元素质量分数。测试样品分别取自坛紫菜主要产地江苏启东，浙江象山和福建福鼎，采用两步消解法处理样本，先加入消解剂常温静置消化，后三梯度变温（100 ℃，180 ℃，100 ℃）微波消解。样品定量采用标准曲线法，消解剂作空白排除测定干扰。本法测定元素相对标准偏差为0.35% ～ 5.14%，砷元素加标回收率为95.8% ～ 105.3%，镉为89.0% ～ 98.0%，铬为93.0% ~ 103.2%，汞为90.5% ～ 96.0%，铅为86.5% ～ 107.5%，锌为94.7% ～ 98.4%。研究中发现，江苏启东样品中镉质量分数为0.57 mg·kg^－1，铅为2.15 mg·kg^－1；浙江象山样品中汞为1.54 mg·kg^－1；福建福鼎样品锌为161.12 mg·kg^－1，均出现不同程度的重金属超标现象。表3参10

Analysis of metallic elements in Porphyra haitanensis by ICP-OES

To explore the altar of the rapid detection Porphyra haitanensis metal elements,a new method for analyzing the contents of metallic elements,such as As,Cd,Cr,Hg,Pb,and Zn in Porphyra haitanensis by inductively coupled plasma-optical emission spectrometry（ICP-OES） was developed.Three representative areas were chosen at Qidong（Jiangsu Province）,Xiangshan（Zhejiang Province）,and Fuding（Fujian Province） to collect the samples.The samples processing procedures involve two steps,being first decomposed by standing digestion,and then by microwave digestion at different temperature gradient（100 ℃,180 ℃,100 ℃） each for 10 minutes.Standard curve method was used as quantification of samples;the interference was eliminated by the digestion solvent.This method showed satisfactory precision and accuracy with the relative standard deviation（RSDs） between 0.35% and 5.14%.The recovery rates of As,Cd,Cr,Hg,Pb and Zn were between 95.8% and 105.3%,89.0%-98.0%,93.0% 103.2%,90.5%-96.0%,86.5 %-107.5% and 94.7%-98.4%,respectively.Survey also found that the Cd in Qidong the content is 3.57 mg·kg-1,Pb level 2.15 mg·kg-1;Xiangshan in the sample Hg content is 1.54 mg·kg-1;a sample of Zn in Fuding the content is 161.12 mg·kg-1,from metal content were exceeds bid badly.