Sensitive voltammetric determination of baicalein at thermally reduced graphene oxide modified glassy carbon electrode

This work presents a sensitive voltammetric method for determination of the flavonoid baicalein by using a thermally reduced graphene oxide (TRGO) modified glassy carbon electrode (GCE) in 100mM KCl-10mM sodium phosphate buffer solution (pH7.40). The surface morphology and structure of TRGO investigated by atomic force microscopy, FT-IR spectroscopy and Raman spectroscopy reveal that the TRGO prepared maintained as single or bilayer sheets and with significant edge-plane-like defect sites. The TRGO/GCE modified electrode shows more favorable electron transfer kinetics for potassium ferricyanide and potassium ferrocyanide probe molecules, which are important electroactive compounds, compared with bare GCE and GO/GCE electrodes. The electrochemical behaviors of baicalein at the TRGO/GCE were investigated by cyclic voltammetry, suggesting that the TRGO/GCE exhibits excellent electrocatalytic activity to baicalein. Under physiological conditions, the modified electrode showed linear voltammetric response from 10nM to 10μM for baicalein, with a detection limit of 6.0nM. This work demonstrates that the graphene-modified electrode is a promising tool for electrochemical determination of flavonoid drugs.