Study on Rhizoma Chuanxiong based on capillary electrophoresis with amperometric detection

Abstract A high-performance capillary electrophoresis with amperometric detection (CE-AD) method has been developed for the analysis of seven bioactive ingredients, namely ferulic acid (FA), vanillin, vanillic acid, p-hydroxybenzoic acid, caffeic acid, gallic acid and protocatechuic acid, in Rhizoma Chuanxiong . The effects of several factors such as the acidity and concentration of running buffer, the separation voltage, the applied potential to working electrode and the injection time were investigated. Under the optimum conditions, the seven analytes could be well separated within 21 min at the separation voltage of 16 kV in a 60 mmol/L borax running buffer (pH 8.7). A 300 μm diameter carbon disk electrode has a good response at potential of +950 mV ( vs. SCE) for all analytes. Good linear relationship was established over three orders of magnitude with detection limits (S/N = 3) ranged from 3.3 × 10 −7 to 6.7 × 10 −9  g/mL. This proposed method has been successfully applied for the determination and comparison of different batches of Rhizoma Chuanxiong samples based on their characteristic electrochemical profiles.