Search

A novel poly(3,4-ethylenedioxythiophene):poly(styrene-sulfonate) (PEDOT:PSS) composite film with superior stability in water, adhesion and flexibility, which is very critical for maintaining the long-term stability in water of the PEDOT:PSS film electrode, was easily prepared by introducing a water-soluble, anionic, non-toxic and biocompatible biopolymer (sodium carboxymethyl cellulose, Na-CMC) into a commercially available aqueous dispersion of the conducting polymer (PEDOT:PSS dispersion). The high conducting PEDOT:PSS-CMC film exhibited good flexibility and long-term stability in water after being soaked in water for 35 days. The high performance film electrode with excellent adhesion, long-term electrode stability in water (retaining almost 99.4% of its original activity for 105 days), and electrochemical properties was prepared facilely by drop-coating, and displayed good synergistically enhanced electrocatalytic ability towards the anodic oxidation of harmful substances and nutritional ingredients in edible agro-products, which were employed for its application in electrochemical sensors. The simultaneous or individual detection of maleic hydrazide, salicylic acid, nitrite, sunset yellow, and tryptophan was successfully realized using PEDOT:PSS-CMC/GCE, and exhibited superior sensing stability. All satisfactory results indicated that the introduction of CMC into PEDOT:PSS could improve the flexibility, adhesion, long-term electrode stability in water and electrocatalytic ability, which would provide a promising platform for the application in electrochemical fields of the high performance film electrode, especially the application in electrochemical sensors. [ABSTRACT FROM AUTHOR]

Abstract: A commercially available aqueous poly(3,4-ethylenedioxythiophene):polystyrenesulfonic acid (PEDOT:PSS) as the immobilization matrix of biologically active species for the development of sensing and biosensing devices has not been widely reported due to its swelling and disintegration in aqueous solution. In this paper, a lowly swelling and disintegrating PEDOT:PSS composite films as the electrochemical biosensing platform was successfully developed by the incorporation of the biocompatible binding agent and common ionic liquid. Nafion was selected as a binding agent, mainly because Nafion could provide the biocompatible environment for biologically active species, improve the adhesion and binding force between films and electrode interface, and prevent peeling off of both enzyme molecules and films. 1-Butyl-3-methylimidazolium tetrafluoroborate, one of common ionic liquids, was used for the secondary dopant and enhancer to improve the water-resistance and electrochemical properties of PEDOT:PSS films. Ascorbate oxidase was used as a mode for the development and application of the electrochemical biosensor. The prepared PEDOT:PSS composite modified electrode exhibited the pronounced water-stability. Moreover, the fabricated biosensor displayed an excellent bioelectrocatalytic activity to the oxidation of vitamin C, fast current response, high sensitivity, wide linear range, low detection limit, high bioaffinity and specificity, and satisfactory results in practical application, indicating that the fabricated biosensor has good electrochemical biosensing performance. Meanwhile, the excellent water-stability, repeatability, reproducibility, storage stability, and electrochemical biosensing performance also make PEDOT:PSS composite modified matrix an interesting candidate for the sensing and biosensing application in the near future. [Copyright &y& Elsevier]

Abstract Two novel chiral 3,4-dihydro-2 H -thieno[3,4- b ][1,4]dioxepine (ProDOT)-based electrochemical sensor, employing a pair of glassy carbon electrodes modified with chiral poly(2-Phenyl-propionic acid 3,4-dihydro-2 H -thieno[3,4- b ][1,4]dioxepin-3-ylmethyl ester) (PProDTM-PP), were utilized for the enantioselective detection of chiral 3,4-dihydroxyphenylalanine (DOPA). The enantioselective recognition between chiral PProDTM-PP modified glassy carbon electrodes and chiral DOPA was studied by using different electrochemical technologies. The redox activity and electrochemical stability of chiral PProDTM-PP was good. (R)-PProDTM-PP and (S)-PProDTM-PP showed higher peak current responses toward D -DOPA and L -DOPA, respectively. Furthermore, the recognition efficiencies of chiral PProDTM-PP are between 1.48 and 1.89, which is higher than chiral PEDOT-based electrochemical sensors (around 1.10). The chiral PProDTM-PP provides an alternative to chiral recognition. [ABSTRACT FROM AUTHOR]