A rational design for the selective detection of dopamine using conducting polymers

Abstract

Poly(N-methylpyrrole) (PNMPy), poly(N-cyanoethylpyrrole) (PNCPy) and poly(3,4-ethylenedioxythiophene) (PEDOT) films have been prepared using both single and two polymerization steps for the selective determination of low concentrations of dopamine, ascorbic acid and uric acid in tertiary mixtures.Analysis of the sensitivity and resolution parameters derived from the electrochemical response of such films indicates that PEDOT is the most appropriate for the unambiguous detection of the three species.Indeed, the performance of PEDOT is practically independent of the presence of both gold nanoparticles at the surface of the film and interphases inside the film, even though these two factors are known to improve the electroactivity of conducting polymers. Quantum mechanical calculations on model complexes have been used to examine the intermolecular interaction involved in complexes formed by PEDOT chains and oxidized dopamine, ascorbic acid and uric acid. Results show that such complexes are mainly stabilized by C-HÁ Á ÁO interactions rather than by conventional hydrogen bonds.In order to improve the sensitivity of PEDOT through the formation of specific hydrogen bonds, a derivative bearing a hydroxymethyl group attached to the dioxane ring of each repeat unit has been designed. Poly(hydroxymethyl-3,4-ethylenedioxythiophene) (PHMeDOT) has been prepared and characterized by FTIR, UV-vis spectroscopy, cyclic voltammetry, scanning electron microscopy and atomic force microscopy. Finally, the performance of PHMeDOT and PEDOT for the selective detection of the species mentioned above has been compared.

Flexible Electrodes for Supercapacitors Based on the Supramolecular Assembly of Biohydrogel and Conducting Polymer

“…In order to enhance the electrochemical behavior of the electrode, HMeDOT monomers in aqueous solution were anodically polymerized directly inside the loaded PEDOT/γ-PGA hydrogel. PHMeDOT was chosen for the electrochemical modification of PEDOT/γ-PGA because of the following two reasons: 45,46 (i) the solubility in water of HMeDOT is high, especially when compared with the EDOT monomer, due to the exocyclic hydroxymethyl group;…”

Recent Advances in Electrochemical and Optical Sensing of Dopamine

“…Fabregat et al (2014) in their study used two different conducting polymers, PEDOT and poly (N-methylpyrrole). The amount and morphology of the used polymers with perfectly controlled coating thickness enhanced the sensor response and sensitivity towards the oxidation of DA [222].…”

Plasma surface modification of polymers for sensor applications

“…The implications of this approach were very significant since the utilization of conventional commodity polymers can cause not only a very significant reduction in the economic cost of the detection devices but also opens a new door for the technological reuse of recycled polymers. Regarding to conducting PEDOT and poly(N-cyanoethylpyrrole) (PNCPy), which already were reported to detect dopamine without any treatment ( Figure 11c), 111,112 application of corona discharge at 0.5 J cm -2 in ambient atmosphere during 2 min improved the resolution, sensitivity and selectivity, especially for PNCPy that is unable to discriminate dopamine from interferents without plasma treatment ( Figure 11d).…”