Voltammetric Determination of Bergenin with Graphene Modified Glassy Carbon Electrode

This study utilized a sensitive electroanalytical method for the detection of bergenin in phosphate buffer solution (pH 5.0) with a graphene (GR) and chitosan (CS) nanocomposite modified glassy carbon electrode (GCE). Characterization of CS-GR/GCE was carried out by electrochemical impedance spectroscopy. Electrocatalytic oxidation of bergenin on CS-GR/GCE was greatly enhanced with the improvement of the anodic peak current, which allowed the development of a voltammetric sensor for bergenin determination. Under the optimized conditions with differential pulse voltammetry, the anodic peak responses enhanced linearly with bergenin concentration from 2.0x10(-8) mol/L to 8.0x10(-6) mol/L with the detection limit of 3.6 nmol/L (3 sigma). This electrochemical sensor showed high sensitivity and selectivity, excellent reproducibility and good stability. The analytical application of this sensor was successfully proved by the Tabellae Bergenini Compositae sample detection.