论文部分内容阅读
本文应用氢化物发生原子荧光度法(HG—AFS)对食品、水和生物样品中痕量砷的测定进行了探讨。本方法采用L_(32)(8×4~?)混合正交设计法优选出最佳实验条件,样品经4:1HNO_3—HClO_4消化后,按标准曲线法进行样品分析,在0～500ng/ml区间内线性相关系数γ=0.9985,具有较宽的线性范围。应用硫脲—抗坏血酸一定程度上抑制了在样品中与砷共存的22种元素的干扰。分析测定了国家标准物质研究中心研制的7种一级标准物质中的砷,测定值与标准值吻合,同时分别做不同浓度的加标实验,回收率为90～113%。本方法测砷的最低检出限是0.5ng/ml,乘以取样体积2ml,最小检出量为1ng。
In this paper, hydride generation atomic fluorescence spectrometry (HG-AFS) was applied to the determination of trace arsenic in food, water and biological samples. The optimum conditions were optimized by the hybrid design of L32 (8 × 4 ~?). After the sample was digested with 4: 1HNO_3-HClO_4, the samples were analyzed by standard curve method. The optimum conditions were 0-500ng / ml Inter-range linear correlation coefficient γ = 0.9985, with a wide linear range. The application of thiourea-ascorbic acid to a certain extent inhibited the interference of 22 kinds of elements coexisting with arsenic in the sample. The determination of arsenic in seven kinds of primary standard materials developed by the National Center for Reference Materials was carried out. The measured values were in good agreement with the standard values, and the spiked experiments at different concentrations were performed respectively. The recoveries ranged from 90% to 113%. The minimum detectable limit of detection of arsenic by this method is 0.5ng / ml, multiplied by the sampling volume 2ml, the minimum detection volume of 1ng.