采用基体辅助等离子体表面进样原子发射光谱技术对环境样品中的13种金属元素( Ag, Au, Ba, Cd, Cr, Cu, Eu, La, Mn, Ni, Pb, Sr, Y)进行检测。实验采用滤纸作为样品基体,样品直接滴加在滤纸上。将等离子体射流尾焰烧蚀滤纸表面,滤纸受热燃烧并释放出燃烧热,样品在等离子体辐射热和滤纸燃烧热的共同作用下原子化并激发,即可得到样品的特征光谱。液/固态样品均采用表面进样的方式实现样品引入,无需复杂的流动进样系统,并简化了繁琐的样品处理过程。本方法具有分析速度快(≤15 s)、用样量少(微升/微克级)、装置简洁、操作简单等优点,可实现对大量环境样品的现场高通量分析。在实验优化条件下,样品体积为1μL 时,本方法对以上13种元素的检出限为1.0~88 ng/mL,相对标准偏差为2.3％~6.8％(n=10)。该技术成功用于水样、土壤、海底沉积物等环境样品中金属元素的分析,结果均与理论值吻合。%A novel method for the determination of metallic elements in environmental samples was developed based on the matrix-assisted plasma surface sampling atomic emission spectrometry ( AES system) . A piece of filter paper was used as sample substrate. By direct interaction of the plasma tail plume with the filter paper surface, the filter paper absorbed energy from the plasma source and released combustion heating to the analytes originally present on its surface, thus to promote the atomization and excitation process. Surface sampling was performed in both cases of liquid and solid state analytes. Therefore, no flow injection system was required and sample pretreatment process was simplified. The proposed method provides several advantages, including fast analysis speed ( about 240 samples/h ) , little sample consumption (μL or μg level) , simplicity in instrument design, and also ease of system operation. These advantages made it attractive as a potential miniaturized AES system for in situ and high-throughput elemental analyses. Quantitative analysis of metal ions were achieved in this study for elements Ag, Au, Ba, Cd, Cr, Cu, Eu, La, Mn, Ni, Pb, Sr and Y. Under optimal conditions, the LOD values of the 13 elements ranged from 1. 0 to 88 μg/L. The repeatability, expressed as relative standard deviation ( RSD) from 10 replicates, ranged from 2. 3% to 6. 8%. To validate the proposed method, the system was employed to determine metal elements in standard reference materials of environmental samples. The content of each element was well in agreement with the certified values.
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