Electropolymerizatinon and electrochemical behavior of thionine from different companies on a glassy carbon electrode

In this paper,the electrochemical behaviors of the Poly(THionine)(PTH) modified glassy carbon electrode(GED) were investigated with cyclic voltammetry(CV).It was found that there were different redox properties for the electropolymerized thionine from different companies.The PTH prepared with the thionine from Alfa Aesar Company on the GED appeared two pairs of redox peaks,while the PTHs prepared with another two companies both showed one pair of redox peak in the CV of modified electrode.Additionally,the PTHs prepared with the thionine from Shanghai Guoyao Company and Sigma Company on the GED showed the greater response current and better invertibility in the potential range of-0.45 ~ 0.15 V versus SCE in phosphate buffer solution of pH 6.0.However,the optimum acidity for the electropolymerization of thionine from Alfa Aesar Company on the GCE is pH 7.0.The results are of the practical significance in studying biosensor.