Highly sensitive and selective anodic stripping voltammetric procedure of As(III) determination following double deposition and double stripping steps mode in combination with a flow system

• Published in: Talanta (Oxford) 2025-01, Vol.282, p.126982, Article 126982
• Main Authors: Gęca, Iwona, Korolczuk, Mieczyslaw
• Format: Article
• Language: English
• Subjects: Arsenic; detection limit; Determination; Double deposition and stripping steps; electrodes; Flow system; lakes; Solution exchange; Stripping analysis; voltammetry
• ISSN: 0039-9140; 1873-3573; 1873-3573
• DOI: 10.1016/j.talanta.2024.126982

Double deposition and double stripping steps mode was used for the first time in combination with a flow system for anodic stripping voltammetric determination of As(III) ions. The proposed way of the voltammetric measurements leads to a decrease of the detection limit as compared to the values obtained using a traditional three-electrode system thanks to an initial preconcentration of the analyte on the first working electrode as well as the significant increase of the selectivity of As(III) determination thanks to the application of a flow system. Optimization of the analytical procedure was performed. The calibration curve of As(III) determination was a straight line in the range from 1 × 10−9 to 5 × 10−8 mol L−1. The estimated detection limit was 4.8 × 10−10 mol L−1 (deposition time of 120 s at both working electrodes). The repeatability of the proposed procedure calculated as RSD% for As(III) at a concentration of 1 × 10−8 mol L−1 was 3.8 % (n = 7). The tolerable limit of Cu(II) excess was significantly increased thanks to the solution exchange after the first deposition step. The correctness of the proposed procedure was confirmed by analysis of a real water sample and lake water certified reference material by obtaining satisfactory recovery values. [Display omitted] •Novel voltammetric procedure for As(III) determination was developed.•Double deposition and stripping step mode was combined with a flow system first-time.•Detection limit was decreased as compared to that obtained in three-electrode system.•Proposed way of measurements leads to a significant decrease of interference effects.•Impact of Cu(II) ions on As(III) analytical signal was significantly minimized.