Construction and Evaluation of a Gold Tubular Electrode for Flow Analysis: Application to Speciation of Antimony in Water Samples

Abstract

A tubular gold electrode (TGE) is described for the first time by summarizing the important aspects of its construction and evaluation. Applicability of the TGE is evaluated in the speciation of Sb(III) and Sb(V) using anodic stripping voltammetry in a single flow manifold. Studies with surface active interferences and metallic cations were performed. The proposed conditions for antimony determination showed good tolerance towards cationic, anionic and nonionic surface active substances. A linear response for antimony was obtained for solutions containing significant amounts of several metallic cations. Linear calibration curves for Sb(III) were obtained in the range 1 -10 ppb with a detection limit of 0.19 ppb (CV ¼ 2.91%, n ¼ 5, [Sb(III)] ¼ 5 ppb). For Sb(V), linear calibration curves were in the range 1 -15 ppb with a detection limit of 0.32 ppb (CV ¼ 1.41%, n ¼ 5, [Sb(V)] ¼ 5 ppb). The figures of merit achieved sustain for the good applicability of the proposed method as it allows the determination of antimony at levels below maximum values permitted in consuming waters. Results of antimony concentration determined in water samples were validated against the ICP-MS reference procedure or compared with reference water samples.

Adsorptive anodic stripping voltammetric determination of antimony(III) on a glassy carbon electrode using rivastigmine as a new chemical receptor

“…These are summarized in Table 3. As can be seen from this table, the value of LOD is lower than most of the reported electrochemical methods [15,16,[21][22][23]26,[31][32][33]36,[38][39][40]43,45,49,52]. Moreover, the results of the interference studies showed that the selectivity of the proposed method is quite high.…”

“…Hydrochloric acid solution is mostly used as a supporting electrolyte for the voltammetric determination of antimony [15,49]. In this study, in order to see the effect of a different medium on the peak current in Sb(III) of 1.0 × 10 −5 mol L −1 , a different supporting electrolyte and pH were used.…”

Application of Non‐Stop‐Flow Differential Pulse Voltammetry at a Tubular Detector of Silver Solid Amalgam for Electrochemical Determination of Lomustine (CCNU)

“…Another type of electrode (detector) used is a tubular one. As examples of electrochemical materials for tubular detectors (TD) could be platinum 3, 4, gold 5, bismuth 6 or carbon materials 7, 8. The main advantage of TD is the fact that it is a part of a flow system and that it can be placed in any suitable cell with reference and auxiliary electrodes.…”

Development of a chromatographic low pressure flow injection system using amperometric detection: Application to the analysis of niacin in coffee

“…The working electrode was constructed as follows. A shielded electrical wire was fixed over the non-polished side of the BDD disk using conductive silver resin and metallic silver, as described elsewhere (Santos, Lima, Quinaz, Rodríguez, & Barrado, 2007). After the hardening of the conductive resin, the BDD disk was then fixed with a non-conductive epoxy resin at the top of a PMMA cylinder with 7 mm e.d., 4 mm i.d., with the BDD polished side facing the outer part of the PMMA cylinder.…”