Study on the Electrochemical Properties of Salvianic Acid A Sodium and its Analytical Application

The electrochemical behavior of salvianic acid A sodium (SAS), a main active content in Chinese herbal medicine (CHM), was studied for the first time by cyclic voltammetry (CV). A new electroanalytical method of SAS was erected using differential pulse voltammetric (DPV) technique. In pH 3.3 britton‐robinson (B‐R) buffer solution, the medicine showed a pair of redox peaks driven by adsorption. The electrode process involved two electrons and two protons transformation with apparent rate constant (ks) of 2.85 s^?1 and transfer coefficient (α) of 0.81. Based on understanding the electrochemical process of SAS at the glassy carbon electrode (GCE), analysis of SAS can be realized. The oxidation peak currents showed linear with the concentrations of SAS in the range of 5.45 × 10^?8 to 1.09 × 10^?5 M. The limit of detection was 5.45 × 10^?8 M. The proposed method has high sensitivity, wide linear range, and was successfully applied to quantitative determination of the SAS in Rukuaixiao Tablets.