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

✍ Scribed by D.W. Bryce; A. Izquierdo; M.D.Luque De Castro

• Publisher: Elsevier Science
• Year: 1995
• Tongue: English
• Weight: 491 KB
• Volume: 308
• Category: Article
• ISSN: 0003-2670
• DOI: 10.1016/0003-2670(94)00626-w

✦ Synopsis

A continuous method for the determination of selenium based on flow-injection anodic stripping voltammetry is proposed. After the deposition/preconcentration of Se(W) on a gold working electrode at an applied voltage of -0.4 V, an anodic scan from -0.4 to 1.16 V was applied, whereby the selenium was stripped at a potential of 0.912 V. The current produced was proportional to the Se(W) concentration in the sample. Off-line reduction of Se(V1) to Se(IV) gave the original Se(W) + Se(V1) concentration so that the Se(V1) concentration could be calculated as the difference between the two results. Interfering divalent cations were removed by on-line separation by use of a cation exchange column prior to the injection valve. The method has a linear determination range between 5 and 100 ng ml -' with a correlation coefficient, r2, of 0.9969 and an R.S.D. < 4.7%. A certified reference material and Se(IV) and Se&I) added to water samples give excellent recoveries.