Voltammetric determination of chlorogenic acid in pharmaceutical products using poly(aminosulfonic acid) modified glassy carbon electrode

In this work, a poly(aminosulfonic acid) modified glassy carbon electrode was fabricated and the electrochemical behavior of chlorogenic acid (CGA) was studied by cyclic voltammetry. Compared with a bare glassy carbon electrode, the modified electrode exhibits excellent catalytic effect on the electrochemical redox of CGA. Utilizing this catalytic effect, a sensitive and selective electrochemical method for the determination of CGA was developed. The analytical parameters were optimized. Under the optimized conditions, the oxidation peak current is linearly proportional to the concentration of CGA in the range from 4.00 × 10−7 to 1.20 × 10−5 mol/L and the detection limit is 4.00 × 10−8 mol/L. Further, the performance of the proposed method has been validated in terms of linearity (r = 0.9995), recovery (96.3–102.8%), reproducibility (RSD ＜ 4.0%, n = 6) and robustness. The developed method has been successfully applied for the determination of CGA in a variety of pharmaceutical products.