C. L. Housmyer, R. Lewis, H. J. Keily
1983
Citations
0
Influential Citations
1
Citations
Journal
Analytica Chimica Acta
Abstract
Abstract 1-[5-(Tetradecyloxy)-2-furanyl]ethanone and 5-(tetradecyloxy)-2-furancarboxylic acid as well as its esters are oxidizable at a carbon paste electrode in acetonitrile—aqueous buffer solutions. Voltammetric peak potentials for the acid decrease smoothly from 1.25 to 1.07 V vs. SCE as the electrolyte pH increases from 1.4 to 6.5. The peak potential remains constant above this pH. The remaining compounds oxidize at 1.3 V independent of pH. Controlled potential coulometry produces a transfer of two electrons at 1.3 V. The oxidative step destroys the mahor ultraviolet chromophore at ca. 300 nm but the products are unknown. Peak currents from wide ranging pH media re quantitatively useful. They are selective for the intact furanyl ring systems in the presence of their acidcatalyzed degradation products. The compounds are extracted into the carbon paste electrode in varying degrees in relation to their lipphilicities so that electrode contact time with sample solutions must be controlled for reasonable accuracy. In flowing streams, pre-electrolysis extraction is avoided and the carboxylic acid compound can be accurately quantified by high-performance liquid chromatography with electrochemical detection. One dat set at k′ = 1.5 showed a linear range of 1–300 ng injected, with a sensitivity of 0.295 ± 0.001 nA ng-1.