Thị Hue Nguyen, Van Hop Nguyen, Thai Long Hoang, Hai Phong Nguyen, Uyen Tran Ha, Quoc Hung Le, Nhi Phuong Nguyen
University of Sciences, Hue University, Hue 530000, Vietnam.
Institute of Chemistry, Vietnam Academy of Science and Technology, Ha Noi 100000, Vietnam.
J Environ Public Health. 2020 May 14;2020:1347836. doi: 10.1155/2020/1347836. eCollection 2020.
Development of adsorptive stripping voltammetry (AdSV) combined with prepared bismuth film electrode ( BiFE) on glassy carbon disk surface using diethylenetriamine pentaacetic acid (DTPA) as a complexing agent and NO as a catalyst to determine the trace amount of chromium (VI) is demonstrated. According to this method, in the preconcentration step at = -800 mV, the bismuth film is coated on the surface of glassy carbon electrodes simultaneously with the adsorption of complexes Cr(III)-DTPA. In addition to the influencing factors, the stripping voltammetry performance factors such as deposition potential, deposition time, equilibration time, cleaning potential, cleaning time, and technical parameters of differential pulse and square wave voltammetries have been investigated, and the influence of Cr(III), Co(II), Ni(II), Ca(II), Fe(III), SO , Cl, and Triton X has also been investigated. This method gained good repeatability with RSD <4% ( = 9) for the differential pulse adsorptive stripping voltammetry (DP-AdSV) and RSD < 3% ( = 7) for the square wave adsorptive stripping voltammetry (SqW-AdSV), and low limit of detection: LOD = 12.10 M ≈ 0.6 ppb (at a deposition potential ( ) of -800 mV and the deposition time ( ) of 50 s) and LOD = 2.10 M ≈ 0.1 ppb (at = -800 mV and = 160 s) for the DP-AdSV and SqW-AdSV, respectively. This method has been successfully applied to analyze chromium in natural water.
本文展示了吸附溶出伏安法（AdSV）与在玻碳圆盘表面制备铋膜电极（BiFE）相结合的方法，该方法使用二乙烯三胺五乙酸（DTPA）作为络合剂，以NO作为催化剂来测定痕量铬（VI）。根据该方法，在-800 mV的预富集步骤中，铋膜在玻碳电极表面沉积的同时，Cr（III）-DTPA络合物也被吸附。除了影响因素外，还研究了溶出伏安法的性能因素，如沉积电位、沉积时间、平衡时间、清洗电位、清洗时间以及差分脉冲和方波伏安法的技术参数，同时也研究了Cr（III）、Co（II）、Ni（II）、Ca（II）、Fe（III）、SO、Cl和Triton X的影响。该方法具有良好的重复性，差分脉冲吸附溶出伏安法（DP-AdSV）的相对标准偏差（RSD）<4%（n = 9），方波吸附溶出伏安法（SqW-AdSV）的RSD<3%（n = 7），检测限低：DP-AdSV在沉积电位（E）为-800 mV、沉积时间（t）为50 s时，检测限为1 × 10⁻¹² M≈0.6 ppb；SqW-AdSV在E = -800 mV、t = 160 s时，检测限分别为2 × 10⁻¹² M≈0.1 ppb。该方法已成功应用于天然水中铬的分析。
