Chronoamperometric Determination of Luteolin with Copper Nanocluster/Graphene Modified Glassy Carbon Electrode

The copper nanocluster/graphene modified glassy carbon electrode (abbreviated Cu/GP/GCE) was prepared, and the structure and property of the modified electrode were characterized by TEM, SEM, AC impedance and cyclic voltammetry. It was found that the sensor had synergistic electrocatalytic activity to the oxidation of luteolin. Based on this fact, a method of chronoamperometry for the determination of luteolin was proposed. Linear relationship between values of peak current and concentration of luteolin measured at the potential of 0.8 V in PBS of pH 4.0 was kept in the range of 7.0×10-8-3.0×10-6mol·L-1, with value of detection limit (3S/N) of 3 ×10-8mol·L-1. The modified electrode was used in the determination of luteolin in the ethyl acetate extract of chrysanthemum, giving results in consistency with those obtained by HPLC. Values of RSD (n=5) were found less than 6.0%.