Graphite-ethylene/propylene/diene terpolymer composite electrodes. A new electrode material for electrochemical detection

The preparation and electroanalytical performance of a new composite electr ode material, fabricated by mixing graphite and the ethylene/propylene/dien e (EPD) terpolymer is reported. The voltammetric and flow-injection with am perometric detection responses at this composite electrode of several subst ances of different solubilities in water are discussed and compared with th ose obtained at graphite-Teflon composite and glassy carbon electrodes. An EPD content around 2% ensures good compactness of the material and an adequ ate conductivity. Under flowing conditions, these electrodes show better si gnal-to-background ratios than those obtained with the other electrode mate rials tested. Furthermore, the new electrodes show very good resistance to fouling with no need of electrode surface pretreatment. The presence of a h igh content of organic solvent in the carrier solution produces a sharp dec rease in the amperometric current thus limiting the advantageous use of the graphite-EPD composite electrodes to predominantly aqueous media.