Influence of Chemical and Structural Properties of Functionalized Polythiophene‐Based Layers on Electrochemical Sensing of Atrazine

Abstract

Sensitive layers based on conducting homopolymer [poly(3,4-ethylenedioxythiophene), denoted PEDOT] and copolymers [molecularly imprinted and non-imprinted poly(EDOT-co-3-thiophene acetic acid), denoted MICP and NICP, respectively] are electrosynthesized on gold substrates and used for the electrochemical detection of atrazine. These layers are characterized by cyclic voltammetry, ATR-FTIR spectroscopy, optical profilemetry, and AFM microscopy in order to study the effect of the chemical functionalities and of the structural properties of these conducting polymers on the physical chemistry of the interaction with atrazine targets and with the aim to improve the sensitivity of the recognition process. In particular, due to the presence in their backbones of preshaped functionalized cavities which keep the molecular memory of the targets, MICP layers show remarkable sensitivity, a low detection limit (10(-9) mol L(-1)), and a large linear range of detection (10(-8) to 10(-4) mol L(-1)), as demonstrated by square-wave voltammetry.

Radiation‐Induced Synthesis of Nanostructured Conjugated Polymers in Aqueous Solution: Fundamental Effect of Oxidizing Species

“…[23] Starting from EDOT monomers, radiolysis enabled us to prepare PEDOT under very soft conditions: in water in the absence of any solutes, at ambient temperature, and in open air. [6,9,[24][25][26] If compared with the usual electrochemical methods, this new g-ray-based radiolytic method presents some advantages concerning the easy preparation of the samples, for which no supporting electrolyte is needed, and the ability to work under atmospheric conditions without purging solutions with an inert gas. After deposition onto a sub-Synthesis of conjugated poly (3,4-ethylenedioxythiophene) (PEDOT) polymers is achieved through the radiolysis of N 2 O-saturated aqueous solutions of 3,4-ethylenedioxythiophene by using two different oxidizing species: HOC (hydroxyl) and N 3 C (azide) radicals.…”

“…strate, radiosynthesized PEDOT-containing films were shown to present optical and electrical properties close to those of homologous PEDOT materials we had already electrosynthesized. [6,9,[24][25][26] If compared with the usual electrochemical methods, this new g-ray-based radiolytic method presents some advantages concerning the easy preparation of the samples, for which no supporting electrolyte is needed, and the ability to work under atmospheric conditions without purging solutions with an inert gas. Besides, contrarily to the electrochemical method, which leads to the direct deposition of conducting polymers onto conducting substrates, the radiolysis method leads to the formation of conducting polymers dispersed in water, which enables their further deposition over conducting and even nonconducting surfaces.…”

Artificial Biosensors: How Can Molecular Imprinting Mimic Biorecognition?

“…Therefore, there is increasing interest in engaging electropolymerization in the preparation of MIP films, both conducting and nonconducting [14,15]. For this purpose, MIP films are deposited from solutions containing functional monomers (e.g., monomers 3-11 with embedded electropolymerizable moieties and functional [ 5 0 _ T D $ D I F F ] carboxy, amine, or hydroxy groups), template molecules, and suitable cross-linking monomers [16][17][18][19][20][21][22][23][24][25][26][27].…”

Functionalized polythiophenes: Recognition materials for chemosensors and biosensors of superior sensitivity, selectivity, and detectability

“…Apart from these tailor-synthesized thiophene derivatives, commercially available thiophene derivatives have also been used for imprinting of analytes as such atrazine [180][181][182], nicotine [183], and terbutylazine, even in an aqueous solution [184]. With X-ray photoelectron spectroscopy (XPS) (Fig.…”