The behaviour of an electrochemical detector used in liquid chromatography and continuous flow voltammetry. Part 2. Evaluation of low-temperature isotropic carbon for use as an electrode material

Unalloyed Pyrolyte, a low-temperature isotropic carbon (LTIC) material is evaluated electrochemically for use as an electrode material in h.p.l.c. thin-layer electrochemical detection cell systems. LTIC is compared to carbon paste electrode material in all systems studied, and to glassy carbon impregnated with ceresin wax in the hexacyanoferrate(II)/(III) redox system. Electrode areas, residual currents, and potential windows are described. Quantitative kinetic studies are reported for the hexacyanoferrate(II)/(III) redox pair in 2.0 M KCl, and rate constants are given. Quantitative rate constant studies are also reported for o-dianisidine in 1.0 M H ₂SO ₄. Finally, qualitative rate comparisons are made by cyclic voltammetric techniques between carbon paste and LTIC electrode materials for maetanephrine, normetanephrine, adrenaline, noradrenaline, dopamine, 3,4-dihydroxyphenylalanine, 5-hydroxytryptophan, and chlorpromazine in chemical systems reflecting previous applications of h.p.l.c. with electrochemical detection.