The selective detection of dopamine at a polypyrrole film doped with sulfonated β-cyclodextrins

Abstract

a b s t r a c t A highly selective dopamine sensor was fabricated by doping polypyrrole with a sulfonated ␤-cyclodextrin. This composite material enabled the selective sensing of dopamine in the presence of a large excess of ascorbic acid and prevented the regeneration of dopamine through the homogeneous catalytic reaction of the ascorbate anion with the dopamine-o-quinone. A single redox wave, corresponding to the oxidation of dopamine, was observed in dopamine/ascorbate mixtures, giving a truly selective dopamine sensor. The limit of detection was measured as 3.2 × 10 −6 M for dopamine.

Electrochemical Sensing of Dopamine Using a Dodecylsulfate Doped Polypyrrole Film

“…Upon reversal of the potential, a cathodic peak, E p C , at 125 mV vs. SCE is observed, corresponding to the reduction of dopamine-o-quinone back to DA. This is consistent with the well-known quasi-reversible electrochemistry of DA [1]. Although the peak potentials are similar at the bare and polymer-modified electrode, it is evident that the peak currents are significantly higher at the SDS-doped polypyrrole film, clearly showing that the DA is oxidized at the polymer interface and not at the gold substrate.…”

Molecularly imprinted polypyrrole films: Some key parameters for electrochemical picomolar detection of dopamine

“…It is worth to note that a near 10 pmol detection limit rests on the combination of several parameters: measurements in favorable conditions, electrode nature, imprinted conducting polymer, optimized MIP film thickness, SWV technique of detection, recognition medium. Comparison with previously published results obtained at modified electrodes by PPy films and used for the detection of dopamine [53] and ephedrine [54], the detection limit was within the micromolar range, acquired with thicker films (thickness > 500 nm). In this work, the high performance films are much thinner (thickness $ 100 nm).…”

Electrochemical Characterisation of Polypyrrole Doped with p‐Sulfonatocalix[4]arene

“…4. p-tert-butylcalix [4] ployed as an electrochemical sensor for dopamine reproducible cyclic voltammograms could be recorded up to potentials of 0.900 V vs. SCE [38].…”