Electrochemical behavior of paclitaxel and its determination at glassy carbon electrode

The electrochemical behavior of paclitaxel drug was studied at a glassy carbon electrode in phosphate buffer solutions using cyclic and differential-pulse voltammetric techniques. The oxidation process was shown to be irreversible over the pH range (3.0–10.4) and was diffusion controlled. Effects of anodic peak potential (E_p), anodic peak current (I_pa), scan rate, pH, heterogeneous rate constant (k⁰), etc have been discussed. A possible electro-oxidation mechanism was proposed. An analytical method was developed for the determination of paclitaxel in phosphate buffer solution at pH = 7.0 as a supporting electrolyte. The anodic peak current varied linearly with paclitaxel concentration in the range 1.0 × 10^?6 M to 1.0 × 10^?5 M with a limit of detection (LOD) of 1.23 × 10^?8 M and limit of quantification (LOQ) of 4.10 × 10^?8 M. The proposed method was successfully applied to the determination of paclitaxel in pure and real samples.