PEDOT composite matrix for determination of ascorbic acid, dopamine and uric acids

There has been growing interest in developing advanced materials for electrochemical sensors. Poly(3,4-ethylenedioxythiophene) (PEDOT) is a conductive polymer with good stability and processability. Incorporating carbon nano spheres (CNSs) and carbon nano tube (CNTs) into PEDOT significantly enhance its electrochemical properties. The PEDOT films were synthesized through electropolymerisation method. The investigation highlights the voltammetric methods and polymer-nanomaterials composite electrodes for the simultaneous electrochemical sensing of ascorbic acid (AA), dopamine (DA) and uric acid (UA). While the CNSs and CNTs are incorporated into the PEDOT matrix and the electrodes are named as GCE/PEDOT/CNSs and GCE/PEDOT/CNTs for the enhanced peak separations between the molecules and also to enhance the sensitivity. The prepared GCE/PEDOT/CNTs nanocomposite exhibited superior electrochemical activity compared to the unmodified GCE/PEDOT and also better activity compared to GCE/PEDOT/CNSs. The detection limits (S/N = 3) of 11.5 µM, 0.08 µM, 0.40 µM, are obtained for AA, DA and UA respectively. The electrostatic interaction, preconcentration and enhanced charge transfer processes are responsible in the well separated peaks in PEDOT/CNSs and PEDOT/CNTs modified electrodes comparted to the unmodified PEDOT.