Determination of Epinephrine at Different Types of Carbon Paste Electrodes

Abstract

The voltammetric behavior of epinephrine was investigated by differential pulse voltammetry (DPV) at a carbon paste electrodes (CPE) made of different carbon powders – CR-2, glassy carbon (GC) microparticles, and single-wall carbon nanotubes (SWNT). In Briton-Robinson (BR) buffer solution pH 6, the linear dependence was found for the determination of epinephrine by the given method in the concentration ranges of 1·10−6–1·10−4 (CR-2), 1·10−6–1·10−4 (GC microparticles) and 4·10−6–1·10−4 (SWNT) mol·dm−3. Limits of detection were 8·10−7, 8·10−7, and 2·10−6 mol·dm−3, respectively. The best results were obtained employing CPE containing carbon paste with 50% (m/m) of SWNT, a linear dynamic range being 4·10−7–1·10−4 mol·dm−3 and a limit of detection 2·10−7 mol·dm−3. The attempt to increase the sensitivity by adsorptive accumulation of epinephrine was not successful.