Applications of a versatile sol-gel derived renewable electrode for capillary electrophoresis

A new electrode has been developed and applied for amperometric detection i n capillary electrophoresis (CE), comprised of carbon sol-gel composite mat erial. The versatility of the sol-gel technique permits the flexible config uration of the electrode. The performance of such a sol-gel carbon composit e electrode (CCE) is first evaluated in a typical CE application for the de tection of purine-based compounds, Application of the CCE is also demonstra ted for the detection of phenolic compounds in a micellar system. Separatio n resolution for non-ionic phenolic compounds can significantly be enhanced by introducing sodium dodecyl sulfate (SDS) at a concentration above its c ritical micelle concentration (cmc) to the buffer. Another design of the CC E incorporating the electrocatalyst Cu2O is employed for the analysis of su gars and organic acids based on dynamic modification with cetyltrimethylamm onium bromide (CTAB). It has been found that the pl presence of surfactant ill the separation buffer does not adversely influence the electrochemical detection using a sol-gel derived carbon electrode.