Abstract

Anion-exchange chromatography (Hamilton, PRP-X100) with hydride-generation atomic fluorescence spectrometry (HG-AFS) is commonly used for selenium (Se) speciation analysis in environmental and biological samples. However, retentions of Se species are often different with different mobile phases. To address it, this study systematically investigated mobile phases based on ammonium salts to obtain good resolution of Se species. Various mobile phases, including NH₄H₂PO₄, NH₄Ac, NH₄NO₃ and (NH₄)₂HPO₄, were tested. The best result was obtained with a mobile phase containing 60 mmol L⁻¹ (NH₄)₂HPO₄ at pH 6.0, where the separation of Se species, including selenite [Se(IV)], selenate [Se(VI)], selenocystine (SeCys) and selenomethionine (SeMet), was achieved within 10 min with reasonable resolution. In addition, the recoveries of SeCys, Se (IV), SeMet and Se (VI) in the Se-enriched samples were 95.72 ± 1.60%, 106.89 ± 2.20%, 93.28 ± 2.82% and 91.38 ± 1.27%, respectively. Finally, the proposed method was validated for the determination of Se species in Nicotiana tabacum tissues.

摘要

阴离子交换色谱 (Hamilton, PRP-X100) 与氢化物发生原子荧光光谱 (HG-AFS) 常用于环境和生物样品中的硒 (Se) 形态分析。然而，不同流动相对 Se 种类的保留通常是不同的。为了解决这个问题，本研究系统地研究了基于铵盐的流动相，以获得对 Se 物质的良好分辨率。测试了各种流动相，包括NH ₄ H ₂ PO ₄、NH ₄ Ac、NH ₄ NO ₃和(NH ₄ ) ₂ HPO ₄。使用含有 60 mmol L ^-1的流动相获得最佳结果(NH ₄ ) ₂ HPO ₄在 pH 6.0 条件下，在 10 分钟内实现了硒物质的分离，包括亚硒酸盐 [Se(IV)]、硒酸盐 [Se(VI)]、硒代胱氨酸 (SeCys) 和硒代甲硫氨酸 (SeMet)以合理的分辨率。此外，富硒样品中 SeCys、Se (IV)、SeMet 和 Se (VI) 的回收率分别为 95.72 ± 1.60%、106.89 ± 2.20%、93.28 ± 2.82% 和 91.38 ± 1.27%。最后，验证了所提出的方法可用于测定烟草组织中硒的种类。