Electrochemical behavior and determination of baicalin on a glassy carbon electrode modified with molybdenum disulfide nano-sheets

• A simple, cost-efficient and rapid determination method of baicalin is proposed.
• The method is based on the MoS2 nano-sheets-modified glassy carbon electrode.
• It was successfully applied to determine baicalin in pharmaceutical preparations.

In this study, a molybdenum disulfide (MoS2) nano-sheets-modified glassy carbon electrode (GCE) was prepared, and the electrochemical behavior of baicalin on the proposed electrode was investigated by cyclic voltammetry (CV) in PBS buffer solution (pH 7.0). The experimental results showed that baicalin exhibits enhanced voltammetric response on the MoS2-modified GCE. Based on the enhanced voltammetric response of baicalin on the MoS2-modified GCE, a sensitive and selective electrochemical method for the determination of baicalin was developed by using differential pulse voltammetry (DPV). Various experimental parameters including the pH of supporting electrolyte, amount of MoS2 nano-sheets and accumulation time were optimized. Under the optimized conditions, the oxidation peak current was linearly proportional to the baicalin concentrations in the range of 1.25 × 10− 7 M–1.25 × 10− 5 M, and the detection limit (S/N = 3) was calculated to be 5.0 × 10− 8 M. The developed method was successfully used to detect baicalin in pharmaceutical samples with a recovery of 97–109% and a relative standard deviation (RSD, n = 6) < 6%.