Fabrication and application of a novel modified electrode based on multiwalled nanotubes/Cerium(III) 12-tungstophosphoric acid nanocomposite

A novel multiwalled nanotubes (MWNTs)/Cerium(III) 12-tungstophosphoric acid (CePW) nanocomposite film glassy carbon electrode was prepared in this paper. Electrochemical behaviors of the CePW/MWNTs modified electrode were investigated by electrochemical impedance spectroscopy (EIS) and cyclic voltammetry (CV). This modified electrode brought new capabilities for electrochemical devices by combining the advantages of carbon nanotubes, rare-earth, and heteropoly-acids. The results demonstrated that the CePW/MWNTs modified electrode exhibited enhanced electrocatalytic behavior and good stability for the detection of guanine and adenine in 0.1 M PBS (pH 7.0). The experimental parameters were optimized and a direct electrochemical method for the simultaneous determination of guanine and adenine was proposed. The detection limit (S/N=3) for guanine and adenine was 2.0 x 10(-8) M and 3.0 x 10(-8) M, respectively. Further, the acid-denatured calf thymus DNA was also detected and the result was satisfied.