Determination of Rutin in Green Tea Infusions Using Square-Wave Voltammetry with a Rigid Carbon-Polyurethane Composite Electrode

This paper presents a comparative study on the electrochemical behavior of the flavonoid rutin on a rigid carbon‐polyurethane composite electrode and on a glassy carbon electrode. The electrochemical oxidation reaction of rutin was found to be quasireversible and affected by adsorption on the electrode surface. A square‐wave voltammetric method was developed for determination of rutin in green tea infusion samples using the RCPE electrode and data treatment by a deconvolution procedure. The detection limit achieved in buffered solutions was 7.1×10−9 mol L−1 using the RCPE and 1.7×10−8 mol L−1 using the GC electrode the average reproducibility for five determinations being 3.5%.