Flow-injection anodic stripping voltammetry at a gold electrode for selenium(IV) determination

Sequential Injection Anodic Stripping Voltammetry at Tubular Gold Electrodes for Inorganic Arsenic Speciation

“…The continuous flow mode is based on simple instrumentation, but its greatest drawback is the high consumption of sample and reagent solutions (Muñoz & Palmero, 2004). (Bryce et al, 1995). However, the reduction in the amount of analyte deposited on the electrode surface as a result of the decrease in the contact time between the sample and the working electrode and the dispersion of the sample in the flow manifold results in a decrease of the analytical signal.…”

Development of an Automatic Electrochemical System for Differential Pulse Amperometry and Its Application for Se(IV) Determination

“…One of these voltammograms, acquired in a XY-recorder, was digitalized and included as a frame over Figure 1. The appearance of only one peak for selenium oxidation in the concentration range used in this work is not a problem because only this peak is described in literature for analytical applications [9,15,16].…”

“…Besides, the system developed can be easily adapted for analysis through standard addition method, where the chemical interference would be the same along the whole analytical curve. The detection limit for Se(IV), although higher than some reported in the literature, can be decreased through the use of a longer deposition time (up to 600 seconds) [15], a chemical extraction and preconcentration [17,19], or another geometry for the gold electrode.…”

“…The chemical interference, due to the formation of intermetallic compounds with selenium (cooper interference is the most important [15]) and the consequent decrease in the analytical signal, can be easily minimized by using a preextraction of selenium with pentanol [17] or using cation exchange columns for the retention of interfering species [15]. Besides, the system developed can be easily adapted for analysis through standard addition method, where the chemical interference would be the same along the whole analytical curve.…”

The Effect of Inorganic and Organic Pre-reducing Agents on Selenium Analysis in Tomato Sample using Microwave-Assisted Digestion Followed by FI-HGAAS

“…due to incomplete retention on the column, decomposition of the species, incomplete recovery of the eluate or peak overlap 8 . There are few electrochemical methods that can be applied for selenium speciation in biological fluids and environmental samples 7,9,10 . However, the complete mineralization or conversion of Se(VI) to Se(IV) (the electroactive form) makes sample preparation more complex and increases the risk of sample contamination and of losses of selenium.…”