Amperometric detector with a manganin electrode for microcolumn liquid chromatography

✍ Scribed by K Šlais

• Publisher: Elsevier Science
• Year: 1988
• Tongue: English
• Weight: 661 KB
• Volume: 442
• Category: Article
• ISSN: 1873-3778
• DOI: 10.1016/s0021-9673(00)94461-3

✦ Synopsis

The response of manganin and copper microelectrodes in amino acid solution was evaluated by using slow-scanning voltammetry. Enhancement of the complexation rate of the manganin electrode in relation to the copper electrode is explained on the basis of the properties of the electrode surface. Based on voltammetric measurements, manganin is suggested as a working electrode material for the confined wall-jet microflow-cell of an amperometric detector. The detector performance was tested under the conditions of reversed-phase microcolumn liquid chromatography using selected amino acids and dipeptides as the solutes. Employing flow-rates up to 1 &s, an increase in response corresponding to the l/3 power of the flow-rate was found, which indicates that a diffusion-limited electrode reaction occurs. The minimum detectable concentrations of the amino acids and some dipeptides in the ranges 0.04-0.08 and 0.1-0.25 ~44, respectively, appear promising for application of this detector to trace analysis.