Electrochemical Behaviors of Baicalin at an Electrochemically Activated Glassy Carbon Electrode and Its Determination in Human Blood Serum

Electrochemical behavior of baicalin (BA) at an electrochemically activated glassy carbon electrode (GCE) had been investigated in Britton-Robinson (B-R) buffer solution (pH = 2.87) by cyclic voltammetry (CV) and square wave voltammetry (SWV). The experimental results suggested that the electrode exhibited an electrocatalytic activity toward the redox of BA. The electron transfer coefficient (α) and the standard rate constant (ks) of BA at the electrochemically activated glassy carbon electrode were calculated. The reaction mechanism was proposed and discussed in this work. Under the selected conditions, the reduction peak current was linearly dependent on the concentration of BA in the range of 5.0 × 10−8 to 3.0 × 10−6 mol L−1 (r = 0.9990), with a detection limit of 2.0 × 10−8 mol L−1. The relative standard deviation (R.S.D.) for five times successful determination of 1.0 × 10−6 mol L−1 baicalin were 2.9%. The proposed method was also successfully applied for the determination of BA in human blood serum.