Wroclaw University of Science and Technology, Faculty of Chemistry, Division of Analytical Chemistry and Chemical Metallurgy, Wybrzeze Stanislawa Wyspianskiego 27, 50-370, Wroclaw, Poland.
Wroclaw University of Science and Technology, Faculty of Chemistry, Division of Analytical Chemistry and Chemical Metallurgy, Wybrzeze Stanislawa Wyspianskiego 27, 50-370, Wroclaw, Poland.
Talanta. 2022 Jan 15;237:122921. doi: 10.1016/j.talanta.2021.122921. Epub 2021 Oct 2.
Novel atmospheric pressure glow discharge (APGD) microplasma systems, sustained between a miniaturized flowing anode (FLA) or cathode (FLC) and a He jet, were investigated for the direct determination of Br and Cl, using optical emission spectrometry (OES). The impact of the most crucial operating parameters, i.e., the acid type and its concentration, the discharge current, the gas flow rate, and the sample flow rate, was studied for each of the proposed APGD-based systems. Under the optimized conditions, the analytical figures of merit were determined. The susceptibility to the matrix effects of both developed methods was verified as well. It was found that the mechanism of the analytes transport into the discharge likely relied on the cathode sputtering in the case of FLC-APGD and the formation of the volatile Br and Cl species for FLA-APGD. The DLs of Br and Cl were established to be relatively high, i.e., 0.15 and 1.5 mg L for FLA-APGD and 2.1 and 18 mg L for FLC-APGD. However, both studied methods turned out to be resistant to the presence of foreign ions in a sample, at relatively high concentrations. Hence, the proposed methods could be successfully applied for the determination of Br and Cl in water and juices samples and no major differences between the results obtained using the external standard calibration and the standard addition method were found.
新型常压辉光放电（APGD）微等离子体系统，在微型流动阳极（FLA）或阴极（FLC）和氦气射流之间维持，使用光学发射光谱法（OES）直接测定 Br 和 Cl。研究了最关键的操作参数，即酸的类型及其浓度、放电电流、气体流速和样品流速，对每个提出的基于 APGD 的系统的影响。在优化条件下，确定了分析的度量标准。还验证了这两种方法对基体效应的敏感性。结果发现，进入放电的分析物的传输机制可能依赖于 FLC-APGD 中的阴极溅射，以及 FLA-APGD 中挥发性 Br 和 Cl 物质的形成。建立了 Br 和 Cl 的 DL 值相对较高，分别为 FLA-APGD 为 0.15 和 1.5 mg/L，FLC-APGD 为 2.1 和 18 mg/L。然而，这两种研究方法都对样品中存在的高浓度外来离子具有抗性。因此，所提出的方法可以成功应用于水和果汁样品中 Br 和 Cl 的测定，并且使用外部标准校准和标准添加法获得的结果之间没有发现主要差异。
