A simple and sensitive method is described for the electrochemical determination of shikonin, a widely used anti-tumoral agent, based on its electrochemical oxidation at a nanostructured poly(hydroxymethylated-3,4-ethylenedioxy-thiophene) (PEDOT-MeOH) electrode, which was fabricated by a facile electropolymerization method. Compared with bare and poly(3,4-ethylenedioxythiophene) (PEDOT) electrodes, the PEDOT-MeOH film exhibited a distinctly higher activity for the electrooxidation of shikonin. The PEDOT-MeOH electrode showed a wide linear response for shikonin in the concentration range from 1.0?nM to 10.0?μM with detection limit of 0.3?nM. Furthermore, the PEDOT-MeOH electrode displayed high stability, good reproducibility and high sensitivity for the detection of shikonin.
Shikonin and 3,4-ethylenedioxythiophene (EDOT) were purchased from Biopurify and Aldrich respectively.
