The effect of pulse electropolymerization on the electrochemical properties of polythiophene films

Spectro-Electrochemical Properties of A New Non-Enzymatic Modified Working Electrode Used for Histamine Assessment in the Diagnosis of Food Poisoning

We successfully prepared a non-enzymatic sensor based on a graphene-thiophene composite for histamine detection. The self-assembling properties of the thiophene onto Au support and the high electrical conductivity of graphene encouraged the choice of this type of composite. The composite was deposited via electrochemical polymerization onto the Au layer of a screen-printed microelectrode. The electropolymerization and electrochemical detection of histamine were both achieved by cyclic voltammetry. Two types of electrolytes were used for the electrochemical detection: (a) phosphate buffer solution (PBS), which showed low-intensity redox peaks for histamine; and (b) trichloroacetic acid (TCA) 0.01 M, which showed improved results over PBS and did not damage the microelectrode. For the concentration range of 100-200 mg/kg, the sensor shows a linear regression pattern for the oxidation peak fitted on the equation Ipa = 123.412 + 0.49933 ×x, with R2 = 0.94178. The lowest limit of detection was calculated to be 13.8 mg/kg and the limit of quantification was calculated at 46 mg/kg. These results are important since by monitoring the amount of histamine in a food product, early onset of spoilage can be easily detected, thus reducing foodborne poisoning and food waste (by recycling products that are still edible).

Cation exchange behavior during the redox switching of poly (3,4-ethylenedioxythiophene) films

Poly (3,4-ethylenedioxythiophene), PEDOT, films were synthesized at room temperature by potentiodynamic and potentiostatic step deposition in aqueous solutions containing EDOT monomer and LiClO4. In some solutions, the effect of small amounts of sodium dodecylsulfate, SDS, on the polymerization rate of EDOT and on the stiffness of the obtained PEDOT film was studied. The obtained PEDOT films were transferred in aqueous solutions containing cations with different molar mass, such as H+, Li+, Na+, K+, and Cs+. The apparent molar masses of the exchanged species during potentiodynamic experiments were determined by in situ microgravimetry. These measurements underlined the importance of the electrolyte chosen for electropolymerization process. It is known that SDS anions can be trapped inside the polymer layer during electropolymerization, providing them with a cation exchange behavior. However, even if the PEDOT films were deposited from an electrolyte without SDS, they still acted as cation exchangers.

Optimal strategy based on radiation chemistry for facile and direct synthesis of poly(3-thiophene acetic acid) polymers in water and dichloromethane

γ-Induced polymerization was used as a novel method to easily synthesize nanostructured PTAA polymers in water and dichloromethane.

Electrochemical synthesis of poly(3-thiophene acetic acid) nanowires with water-soluble macromolecule templates

The interactions between template molecules and monomers play a key role in the formation of PTAA nanowires.