Determination of Manganese by Cathodic Stripping Voltammetry on a Microfabricated Platinum Thin–film Electrode

Abstract

In this work, we report on the determination of trace manganese (Mn) using cathodic stripping voltammetry (CSV) using a microfabricated sensor with a Pt thin-film working electrode. While an essential trace metal for human health, prolonged exposure to Mn tends to gradually impair our neurological system. The potential sources of Mn exposure make it necessary to monitor the concentration in various sample matrices. Previous work by us and others suggested CSV as an effective method for measuring trace Mn. The analytical performance metrics were characterized and optimized, leading to a calculated limit of detection (LOD) of 16.3 nM (0.9 ppb) in pH 5.5, 0.2 M acetate buffer. Further, we successfully validated Mn determination in surface water with ~90% accuracy and >97% precision as compared with ICP-MS “gold standard” measurement. Ultimately, with stable, accurate and precise electrochemical performance, this Pt sensor permits rapid monitoring of Mn in environmental samples, and could potentially be used for point-of-use measurements if coupled with portable instrumentation

Considerations for new manganese analytical techniques for drinking water quality management

“…Most research focuses on exploring the sensitivity of Mn detection with different working electrode materials. Materials such as mercury (Piech et al, 2008), carbon (Berg et al, 2016; Pei et al, 2021), platinum (Kang et al, 2017), indium tin oxide (Rusinek et al, 2016), and nanocomposite materials (Rocha et al, 2020) have been used for determining Mn. Even though mercury‐based electrodes provide sensitive determination of Mn in water (Piech et al, 2008), the toxicity of mercury is a concern and thus the stability of the electrode materials is critical, especially for in‐situ detection in water distribution systems.…”

“…Berg et al (2016) determined Mn using stencil‐printed carbon ink electrodes by square‐wave CSV. Kang et al (2017) microfabricated platinum thin‐film electrode for detection on Mn by CSV. Rusinek et al (2016) proved that bare and polymer‐coated indium tin oxide electrodes are effective for Mn detection using CSV in water.…”

“…The sensor was used to determine Mn in natural water samples (Kang et al, 2014). Kang et al (2017) also microfabricated a platinum thin‐film electrode for high sensitivity down to 16.3 nM.…”

Trace manganese detection via differential pulse cathodic stripping voltammetry using disposable electrodes: additively manufactured nanographite electrochemical sensing platforms

“…Electrochemical methods for manganese detection have been reported previously. 2,3,6,[12][13][14][18][19][20][21][22][23][24][25][26] For instance, Rusinek and colleagues 2 developed a new sensor based on polymercoated indium tin oxide for manganese detection in natural water samples. Kang et al 3 utilized a copper-based electrochemical sensor with a palladium electrode to determine manganese in water samples.…”

“…Saterlay and colleagues 20 developed a sono-cathodic stripping voltammetry method using as a working electrode a BDDE for manganese determination in instant tea reaching a very low detection limit of 10 −11 mol L −1 (2 min deposition). However, several procedures using modified electrodes 3,18,22 and/or high-cost electrodes, such as palladium, 3 platinum, 22 and BDDE, 6,20,25 present some drawbacks.…”