A novel lactose biosensor based on electrochemically synthesized 3,4-ethylenedioxythiophene/thiophene (EDOT/Th) copolymer

Abstract

In this study, a new lactose biosensor has been developed in which the 3,4-ethylenedioxythiophene/thiophene (EDOT/Th) copolymer is used as a transducer. The EDOT/Th copolymer was deposited on the glassy carbon electrode to be used as the working electrode. In addition to the working electrode, the three-electrode system was used in both the electrochemical synthesis and in the biosensor measurements. Lactase (β-galactosidase) that catalyzes the breakdown of lactose into monosaccharides (glucose and galactose) and galactose oxidase that catalyzes the oxidation of the resulting galactose were attached to the copolymer by a cross-linker on the modified working electrode. The response of the enzyme electrode to lactose was determined by cyclic voltammetry (CV) at +0.12 V. Enzyme electrode optimization parameters (pH, temperature, enzyme concentration, etc.) were performed. Fourier transform infrared spectroscopy, scanning electron microscopy and CV methods were used to support copolymer formation. In addition, the characteristics of the enzyme electrode prepared in this study (Km, 0.02 mM; activation energy Ea, 38 kJ/mol; linear working range, up to 1.72 mM; limit of detection, 1.9 × 10−5 M and effects of interferents [uric acid and ascorbic acid]) were determined.

Electroactive and Stretchable Hydrogels of 3,4-Ethylenedioxythiophene/thiophene Copolymers

“…In this study, the P­(EDOT- co -Th) copolymers were synthesized through chemical oxidation polymerization according to the literature procedures. , The various molar ratios of the EDOT and Th monomers were utilized to prepare a series of P­(EDOT- co -Th) copolymers (the different feed ratios of EDOT/Th monomers were 9:1, 7:3, 5:5, 3:7, and 1:9, as shown in Table ). We used Fourier transform infrared spectroscopy (FT-IR), thermogravimetric analysis (TGA), dynamic light scattering (DLS) and contact angle measurement techniques to investigate the properties of P­(EDOT- co -Th) copolymers.…”

Synthesis and characterization of a new benzobisoxazole/thiophene derivative polymer and the effect of the substituent on the push/pull properties

“…The difference between the oxidation and reduction potentials is shown in Table 1, where the variation between the oxidation and reduction peaks was observed (close to Δ 1 = 0.3 V and Δ 2 = 0.1 V), which indicates the partial thermodynamic stability of the co‐polymers. On the other hand, when studying the loss of electrons that occurs during the oxidation process, we observe the high kinetic reversibility of each of these processes, and therefore, this new class of material could be used as an electrochemical sensor 56–59 with biocompatibility property (due the addition of thiophene and benzobisoxzole homopolymers) 33–35,38–40 …”

Synthesis and characteristics of some new polythiophene containing α,β‐unsaturated carbonyl groups

“…1 H-NMR [500 MHz, d6-CDCl3, (ppm), J (Hz)]: 7.37 dd, J = 3, J = 5 (H4); 7.41 dd, J = 5 (H5); 7.61 d, J = 1.5 (H2); 7.79 d, J = 16 (H6); 7.3 d, J = 15.5 (H7); 7.94 d, J = 8.5 (H10, H10'); 7.47, d, J = 8.5 (H11, H11'). 13 C-NMR [125 MHz, d6-CDCl3, (ppm)]: 121.3 (C2), 128.9 (C3), 127.1 (C4), 125.2 (C5), 129.8 (C6), 129.4 (C7), 189.3 (C8), 139.1 (C9), 138.7 (C10, C10'), 138.1 (C11, C11'), 136.6 (C12). Calculation for C13H9OSCl: M = 248.5 au.…”

“…[ 1‐5 ] Their chromic characteristics make these polythiophenes outstanding possibility for the fabrication of organic light emitting diodes, [ 6,7 ] organic photovoltaic devides, [ 8,9 ] cells gas, [ 10 ] biomedical applications, [ 11 ] and sensors. [ 12,13 ]…”

“…[1][2][3][4][5] Their chromic characteristics make these polythiophenes outstanding possibility for the fabrication of organic light emitting diodes, [6,7] organic photovoltaic devides, [8,9] cells gas, [10] biomedical applications, [11] and sensors. [12,13] There are many ways to improve properties and solubility of polythiophene, in which, substituted side chains have been presented at the 3-position of thiophene ring to achieve new monomers capable of improving soluble polymers. A lot of studies on synthesized thiophene bearing long groups, [14][15][16] which is a prerequisite for the polymerization of polythiophene derivatives with more regioregular polythiophene backbone.…”