Conducting poly(N-(1-Naphthyl) ethylene-diamine dihydrochloride) electropolymerization, characterization and electroanalytical applications

Abstract

Uniform conducting polymer films of poly(N-(1-Naphthyl) ethylene-diamine dihydrochloride), PNED, were prepared conveniently and reproducibly by the anodic oxidation of the monomer, N-(1-Naphthyl) ethylene-diamine dihydrochloride, NED, in an acidic aqueous solution using the conventional potentiodynamic technique. The different parameters influencing the preparation conditions like monomer concentration, solvent constitution, scan range, scan rate, scan repetition, rotation speed of the working electrode and the type of the substrate were investigated and the optimum preparation conditions are specified. The stability of the prepared films was tested in both aqueous and non-aqueous media. The characteristics of the polymer films and their electrochemical activity towards catalyzing some technologically promising redox reactions were also examined. The films were found to be very stable in aqueous solutions and in some organic solvents like acetone, acetonitrile, and chloroform and dimethyl sulfoxide. The film stability was found to depend on the solution pH. The polymer films were capable of catalyzing the redox processes of several natural products and amino acids e.g. vitamin C and glycine. The polymer film possesses electrochromic properties and the color of the film changes from purple to violet to dark blue and then to brown according to the preparation and/or polarization conditions. The electrochromic properties are related to polaron formation, which subsequently oxidizes to diimine species followed by the oxidation of the aromatic ring. The mechanism of the polymerization process was investigated and discussed. The process involves deprotonation reactions and a head-to-tail coupling of the oxidized monomer with cation radicals.

A Conducting Poly(N-(1-Naphthyl)ethylenediamine dihydrochloride) Nanofibers for the Sensitive and Interference-Free Detection of Dopamine

“…0.68 V, which can be attributed to the formation of NEDA cation radical (NEDA + • ). 24 Additionally, the high density of oxides species on the AGCE surface were also acts as an oxidant to oxidize NEDA molecules to NEDA + • , as similarly observed for the polymerization of phenothiazine, phenoxazine, and phenazine derivatives. 33 This electrochemical and chemical oxidation synergistically increased the kinetics of NEDA + • formation and corroborate the adsorption/interlink of NEDA + • on AGCE surface by both C-N linkage and hydrogen bonding interaction between NEDA + • and AGCE, 33 and NEDA + • and oxides species, respectively.…”

“…During the CV sweeping the continuously formed NEDA + • can undergo successive head-to-tail coupling polymerization to the pre-adsorbed NEDA + • and form PNEDA (Scheme 1). 24,34,35 The CVs of the PNEDA/AGCE at different scan rates (ν) in PBS (pH 7.0) exhibit the increase of both anodic (I pa ) and cathodic (I pc ) peak currents with the increase of the scan rate. Both the I pa and I pc were directly proportional to the scan rate in the potential range from 25−500 mV•s −1 (Insets of Fig.…”

“…23 Electrochemical polymerization of NEDA on a conventional electrode surface in extremely acidic condition was reported by Badawy et al, which exhibited electrochemical redox behavior over a wide potential range (+0.2 to +0.7 V). 24 Therefore, the development of PNEDA nanostructures with significantly negatively shifting redox potential and electrochemically neutral at a potential greater than +0.2 V is significantly important for the detection biomolecules. To the best of our knowledge, no reports are available for the electrochemical detection of DA by using PNEDA-modified electrodes.…”

Kinetics of electropolymerization of 1‐amino‐9,10‐anthraquinone

“…An extensive work is devoted to a new class of organic polymers produced by electropolymerization of various kinds of aromatic compounds (e.g., NH 2 and/or OH groups containingheterocyclic, polynuclear, and vinyl group) owing to the large field of potential applications of the resulting polymers themselves as well as the composite electrode materials 5. Among the polynuclear aromatic compounds, the polynuclear amines containing one NH 2 group such as 1‐amino‐9,10‐anthraquinone 6,7, 5‐amino‐2‐mercapto‐1,3,4‐thiadzole 8, N ‐acetylaniline 9–11 and two NH 2 groups such as 1,8‐diaminocarbazole 12 and N ‐(1‐naphthyl)ethylene‐diamine dihydrochloride) 13 have been used for the preparation of polymeric film‐coated electrodes. The electrogenerated conducting polymer films were deposited on different substrates.…”