A Newly Competitive Electrochemical Sensor for Sensitive Determination of Chrysin Based on Electrochemically Activated Ta2O5 Particles Modified Carbon Paste Electrode

Abstract A novel electrochemically activated doped Ta 2 O 5 particles modified carbon paste electrode (EA‐Ta 2 O 5 ‐CPE) was prepared and applied for selective and sensitive determination of chrysin. X‐ray diffraction (XRD), scanning electron microscopy (SEM), electrochemical impedance spectroscopy (EIS) techniques and cyclic voltammetry (CV) were used to characterize the Ta 2 O 5 particles and investigate the electrochemical response of the sensor. Compared with bare CPE, the doped Ta 2 O 5 modified electrode got much more porous by electrochemical treatment and exhibited larger effective surface area, more reactive site and excellent electrochemical catalytic activity toward the oxidation of chrysin. Under optimum conditions by LSV, the oxidation peak currents responded to chrysin linearly over a concentration range from 5.0×10 −8 to 7.0×10 −6 mol L −1 with a detection limit of 2.0×10 −8 mol L −1 (5.08 ng mL −1 ). The fabricated sensor showed anti‐interference ability against the biological common interferents (i.e. baicalein, baicalin) and provided to be reliable for the determination of chrysin in Chinese medicinal herb Oroxylum indicum and chrysin capsules samples with satisfactory results.