Electrochemical detection of dihydromyricetin using a DNA immobilized ethylenediamine/polyglutamic modified electrode

Abstract

A novel voltammetric sensor, based on DNA immobilized on the surface of an ethylenediamine/polyglutamic (En/PGA) modified glassy carbon electrode (GCE), was constructed and used for determination of dihydromyricetin (DMY). The electrochemical behaviour of DMY at this sensor was investigated in pH 3.6 NaAc-HAc buffer solutions by cyclic voltammetry (CV) and differential pulse anodic voltammetry (DPV). The oxidation of DMY is an adsorption-controlled irreversible process. The oxidation mechanism was proposed and discussed. It was found that the modified electrode exhibited a linear voltammetric response for DMY in the range of 4.0 × 10⁻⁸ mol L⁻¹ to 2 × 10⁻⁶ mol L⁻¹, with a detection limit of 2 × 10⁻⁸ mol L⁻¹. The method was also applied successfully to detect DMY in an ampelopsis sample with satisfactory results.