Department of Analytical Chemistry, Institute of Chemical Sciences, Faculty of Chemistry, Maria Curie-Sklodowska University, 20-031 Lublin, Poland.
Molecules. 2021 Jul 7;26(14):4130. doi: 10.3390/molecules26144130.
An analytical procedure regarding the determination of selenium(IV) by anodic stripping voltammetry exploiting the in situ plated bismuth film electrode is described. Since organics are commonly present in untreated natural water samples, the use of Amberlite XAD-7 resin turns out to be quite important to avoid problems such as the adsorption of these compounds on the working electrode. The optimum circumstances for the detection of selenium in water using differential pulse voltammetry techniques were found to be as follows: 0.1 mol L acetic acid, 1.9 × 10 mol L Bi(III), 0.1 g Amberlite XAD-7 resin, and successive potentials of -1.6 V for 5 s and -0.4 V for 60 s, during which the in situ formation of the bismuth film on glassy carbon and the accumulation of selenium took place. The current of the anodic peak varies linearly with the selenium concentration ranging from 3 × 10 mol L to 3 × 10 mol L (r = 0.9995), with a detection limit of 8 × 10 mol L. The proposed procedure was used for Se(IV) determination in certified reference materials and natural water samples, and acceptable results and recoveries were obtained.
本文描述了一种利用原位镀铋膜电极通过阳极溶出伏安法测定硒（IV）的分析方法。由于未经处理的天然水样中通常存在有机物，因此使用 Amberlite XAD-7 树脂对于避免这些化合物在工作电极上吸附等问题非常重要。使用差分脉冲伏安法技术检测水中硒的最佳条件如下：0.1 mol/L 乙酸、1.9×10 mol/L Bi(III)、0.1 g Amberlite XAD-7 树脂，以及 5 s 的-1.6 V 连续电位和 60 s 的-0.4 V 连续电位，在此期间，玻璃碳上的铋膜原位形成并同时发生硒的积累。阳极峰电流与硒浓度在 3×10 mol/L 至 3×10 mol/L 范围内呈线性变化（r=0.9995），检测限为 8×10 mol/L。该方法已用于测定标准参考物质和天然水样中的 Se(IV)，并获得了可接受的结果和回收率。
