State Key Laboratory of Biogeology and Environmental Geology, China University of Geosciences, Wuhan 430074, China.
Faculty of Materials Science and Chemistry, China University of Geosciences, Wuhan 430074, China.
Anal Chem. 2021 Dec 14;93(49):16393-16400. doi: 10.1021/acs.analchem.1c02940. Epub 2021 Dec 3.
In the present work, a novel, simple, and sensitive method for the direct determination of trace Sb in water samples was developed based on hydrogen-doped solution anode glow discharge-optical emission spectrometry (SAGD-OES). It was found that the vapor generation and excitation of Sb occurred simultaneously in the SAGD, contributing to the significant improvement in the sensitivity of Sb as compared with normal pure He-operated SAGD or solution cathode glow discharge. Besides, the proposed hydrogen-doped SAGD-OES could be operated even at pH = 14, which could reduce the interference of coexisting ions as many metal ions could be precipitated and removed. Our results demonstrated that the proposed method offered good tolerance to the interferences of Li, Na, Ca, Mg, Fe, Ni, Mn, and Zn ions even at a concentration of 50 mg L. Under optimized conditions, the limit of detection of Sb was 0.85 μg L, which was comparable to that of microplasma sources coupled with conventional hydride generation. The linearity of the Sb calibration curve reached > 0.999 in the 5-5000 μg L range. Finally, the accuracy of the proposed method was validated by the determination of certified reference materials [GSB 07-1376-2001 (1) and (2))] and real water samples. The proposed low-power (6 W), green, sensitive, rapid, and robust method provides a promising approach for on-site trace Sb analysis and may also be extended to other elements.
在本工作中，基于掺氢溶液阳极辉光放电-光学发射光谱法（SAGD-OES），开发了一种新颖、简单、灵敏的水样中痕量 Sb 的直接测定方法。研究发现，Sb 的蒸气发生和激发在 SAGD 中同时发生，与正常的纯 He 操作的 SAGD 或溶液阴极辉光放电相比，Sb 的灵敏度显著提高。此外，所提出的掺氢 SAGD-OES 甚至可以在 pH = 14 下运行，这可以减少共存离子的干扰，因为许多金属离子可以沉淀和去除。我们的结果表明，即使在 50mg/L 的浓度下，该方法对 Li、Na、Ca、Mg、Fe、Ni、Mn 和 Zn 等共存离子的干扰具有良好的耐受性。在优化条件下，Sb 的检出限为 0.85μg/L，与微等离子体源与常规氢化物发生法相当。Sb 校准曲线的线性范围在 5-5000μg/L 之间，相关系数大于 0.999。最后，通过测定认证参考物质[GSB 07-1376-2001（1）和（2）]和实际水样验证了该方法的准确性。该低功率（6 W）、绿色、灵敏、快速和稳健的方法为现场痕量 Sb 分析提供了一种有前途的方法，也可扩展到其他元素。
