Voltammetric Behavior of Rutin at a Boron-Doped Diamond Electrode. Its Electroanalytical Determination in a Pharmaceutical Formulation

Abstract

This paper examined for the first time, the possibilities of the usage of a boron-doped diamond electrode for the redox behavior of rutin using cyclic and adsorptive stripping voltammetry. The cyclic voltammograms showed a pair of redox peaks at lower potentials followed by an irreversible oxidation peak at higher positive potential. Using square-wave adsorptive stripping voltammetry, the compound yielded a well-defined voltammetric response in Britton-Robinson buffer, pH 4.0 at +0.48 V (vs. Ag/AgCl) (after 60 s accumulations at a fixed potential of 0.2 V). The calibration curve was linear in the concentration range from 0.01 A mu g mL(-1) to 0.1 A mu g mL(-1) (1.64x10(-8) M - 1.64x10(-7) M). A detection limit of 0.0017 A mu g mL(-1) (2.78x10(-9) M) was observed without any chemical modifications and electrochemical surface pretreatments. As an example, the practical applicability of boron-doped diamond electrode was tested with the measurement of rutin in dietary supplement products.