Anodic Stripping Voltammetric Analysis of Trace Arsenic(III) on a Au-Stained Au Nanoparticles/Pyridine/Carboxylated Multiwalled Carbon Nanotubes/Glassy Carbon Electrode

Abstract

A Au-stained Au nanoparticle (Aus)/pyridine (Py)/carboxylated multiwalled carbon nanotubes (C-MWCNTs)/glassy carbon electrode (GCE) was prepared for the sensitive analysis of As(III) by cast-coating of C-MWCNTs on a GCE, electroreduction of 4-cyanopyridine (cPy) to Py, adsorption of gold nanoparticles (AuNPs), and gold staining. The Py/C-MWCNTs/GCE can provide abundant active surface sites for the stable loading of AuNPs and then the AuNPs-initiated Au staining in HAuCl4 + NH2OH solution, giving a large surface area of Au on the Aus/Py/C-MWCNTs/GCE for the linear sweep anodic stripping voltammetry (LSASV) analysis of As(III). At a high potential-sweep rate of 5 V s−1, sharp two-step oxidation peaks of As(0) to As(III) and As(III) to As(V) were obtained to realize the sensitive dual-signal detection of As(III). Under optimal conditions, the ASLSV peak currents for oxidation of As(0) to As(III) and of As(III) to As(V) are linear with a concentration of As(III) from 0.01 to 8 μM with a sensitivity of 0.741 mA μM−1 and a limit of detection (LOD) of 3.3 nM (0.25 ppb) (S/N = 3), and from 0.01 to 8.0 μM with a sensitivity of 0.175 mA μM−1 and an LOD of 16.7 nM (1.20 ppb) (S/N = 3), respectively. Determination of As(III) in real water samples yielded satisfactory results.

A Review on Cyclic Voltammetric Investigation of Toxic Heavy Metals

“…The World health organization standard for As concentration must be 10 μg/L, but some parts of the World it exceeds the standard concentration. The excessive intake Preparation of the electrode [28].…”

“…Du et al fabricated a novel Au-stained Au nanoparticles/pyridine/carboxylated multiwalled carbon nanotubes/glassy carbon electrode for the detection of Arsenic (III) traces in real water samples using cyclic voltammetry [28]. The fabrication of the electrode is schematically represnted in Figure 6.…”

“…Au/SPE 0.5-12 0.22 [30] Au-Cu/GCE 30-130 5.64 [31] Si/SPCE 5-30 6.2 [29] Au/GCE 0.01-8 0.0033 [28] Au/GCE 0.01-8 0.0167 [28] Table 1.…”