Conductive Polymer Modified Electrode Research

In recent years,conductive polymers are widely utilized in electrode modification,electrochemical and bioelectrochemical sensors.As one of the most environment-friendly conjugated polymers,poly(3,4-ethylenedioxidethiophene)(PEDOT)received dramatically attention and interests in above areas.In this paper,PEDOT was directly deposited onto a carbon paste electrode through potentiostatic technology.The modified electrodes were characterized by FTIR,electrochemical impedance spectroscopy and cyclic voltammety,etc.The results indicated that the modified electrode performed excellent electric conductivity,stability and electrocatalytic ability.Electrochemical behavior of dopamine(DA),uric acid(UA)and ascorbic acid(AA)on bare and PEDOT modified carbon paste electrode was further investigated,and it was found that the redox peaks of the three substrates were clearly separated on the modified electrode owned to the excellent electrocatlytic ability of PEDOT film.On the other hand,it was also proved that the same number of both proton and electron was involved in the electrochemical oxidation on DA,UA and AA.The analysis of DA was studied in the presence of UA and AA,which showed that DA can be determined on PEDOT modified carbon paste electrode in a mixture composed of UA and AA.Differential pulse voltammetry(DPV)and chronoamperometry were employed in the analysis of the DA,and satisfying results were obtained.Under the optimum working conditions,a linear detection range of DA is 60 ??M-1500 ?M,with the detection limits(S/N=3)of 0.37 ?M in DPV experiments.The linear range of DA in chronoamperometric detection is 10?M-1500 ?M,with the detection limit of 3.44 ?M.PEDOT modified carbon paste electrode exhibited easy preparation,anti-interference ability,good reproducibility and stability.