Abstract Six novel azomethines with substituted thiophene central core were synthesized and their... more Abstract Six novel azomethines with substituted thiophene central core were synthesized and their properties are reported. They were obtained by the condensation reaction between 2,5-diamino-thiophene-3,4-dicarboxylic acid diethyl ester and various aldehydes. The imines were characterized by NMR and FTIR spectroscopies and by elemental analysis. DSC measurements revealed that the prepared compounds are molecular glasses (except for one) with high T g varying from 94 and 183 °C. Their redox properties were investigated in solution by cyclic voltammetry and differential pulse voltammetry. It was found that all imines were electrochemically active and showed low values of energy band gap ranging from 1.61 to 1.78 eV. Photoluminescence measurements indicated that they emitted light in solution with quantum yield (Φ PL ) in the range of 1.2–14.3% and in solid state as film and blend with poly(methyl methacrylate) and binary blend with poly(9-vinylcarbazole) (PVK) and (2-(4-tert-butylphenyl)-5-(4-biphenylyl)-1,3,4-oxadiazole) (PDB) with Φ PL form 0.24–1.77% and from 0.52% to 1.66%, respectively. The density functional theory (DFT) was applied for calculating their geometries and frontier molecular orbitals. Their electroluminescence ability was examined in guest-host diode with structure ITO/PEDOT:PSS/PVK:PBD:imine / Al and emission of light with maximum of emission band from 626 to 674 nm was observed. This work demonstrates, to the best of our knowledge, the first example of light emitting devices based on thiophene azomethines as active layer component.
Current trends in the field of neural tissue engineering include the design of advanced biomateri... more Current trends in the field of neural tissue engineering include the design of advanced biomaterials combining excellent electrochemical performance with versatile biological characteristics. The purpose of this work was to develop an antibacterial and neuroprotective coating based on a conducting polymer - poly(3,4-ethylenedioxypyrrole) (PEDOP), loaded with an antibiotic agent - tetracycline (Tc). Employing an electrochemical technique to immobilize Tc within a growing polymer matrix allowed to fabricate robust PEDOP/Tc coatings with a high charge storage capacity (63.65 ± 6.05 mC/cm2), drug release efficiency (629.4 µg/cm2 ± 62.7 µg/cm2), and low charge transfer resistance (2.4 ± 0.1 kΩ), able to deliver a stable electrical signal. PEDOP/Tc were found to exhibit strong antimicrobial effects against Gram-negative bacteria Escherichia coli, expressed through negligible adhesion, reduction in viability, and a characteristic elongation of bacterial cells. Cytocompatibility and neuroprotective effects were evaluated using a rat neuroblastoma B35 cell line, and were analyzed using MTT, cell cycle, and Annexin-V apoptosis assays. The presence of Tc was found to enhance neural cell viability and neurite outgrowth. The results confirmed that PEDOP/Tc can serve as an efficient neural electrode coating able to enhance charge transfer, as well as to exhibit bifunctional biological characteristics, different for eukaryotic and prokaryotic cells.
Novel dyes based on the phenothiazine system D/A–π–D–π–A exhibit that elongation of π-conjugation... more Novel dyes based on the phenothiazine system D/A–π–D–π–A exhibit that elongation of π-conjugation is advantageous in the design of efficient photosensitizers.
In this work novel bisheterocyclic derivatives of alkylcarbazole with A–CZ–A architecture are inv... more In this work novel bisheterocyclic derivatives of alkylcarbazole with A–CZ–A architecture are investigated (CZ stands for alkylcarbazole). The study presents their opto-electronic and electrochemical properties which influence on the possibility of their prospective application. Monomers undergo electropolymerisation with formation of conducting layer of polythiophene derivatives, while presence of chalcone moiety hampers the process. Two-step oxidation processes of polymers results in generation of polaron and bipolaron types of charge carriers on the macromoleculs’ chains. The charge is delocalized over center and side subunits (bithiophene or bithiazole one) in first stage of oxidation. It is possible to influence on the properties of the polymers and their composition by variation of synthesis condition like solvent polarity and applied potential boundaries. Obtained conducting polymers show high stability under ambient conditions. Their energy gap values are estimated with electrochemical and spectroscopic methods.
Abstract In this work we report the synthesis, electrochemical and optical properties of five new... more Abstract In this work we report the synthesis, electrochemical and optical properties of five new, star shaped compounds containing both carbazole and triphenylamine moieties, further endcapped with thiophene or 3,4-ethylenedioxythiophene units. Electrochemical, UV–visible spectroscopy and fluorescence methods were employed to study the properties of these compounds as well as their electropolymers. The basic characteristics such as the band gaps, HOMO and LUMO values, absorption and emission maximum wavelengths of the monomers and the polymers are reported and discussed.
Abstract Six novel azomethines with substituted thiophene central core were synthesized and their... more Abstract Six novel azomethines with substituted thiophene central core were synthesized and their properties are reported. They were obtained by the condensation reaction between 2,5-diamino-thiophene-3,4-dicarboxylic acid diethyl ester and various aldehydes. The imines were characterized by NMR and FTIR spectroscopies and by elemental analysis. DSC measurements revealed that the prepared compounds are molecular glasses (except for one) with high T g varying from 94 and 183 °C. Their redox properties were investigated in solution by cyclic voltammetry and differential pulse voltammetry. It was found that all imines were electrochemically active and showed low values of energy band gap ranging from 1.61 to 1.78 eV. Photoluminescence measurements indicated that they emitted light in solution with quantum yield (Φ PL ) in the range of 1.2–14.3% and in solid state as film and blend with poly(methyl methacrylate) and binary blend with poly(9-vinylcarbazole) (PVK) and (2-(4-tert-butylphenyl)-5-(4-biphenylyl)-1,3,4-oxadiazole) (PDB) with Φ PL form 0.24–1.77% and from 0.52% to 1.66%, respectively. The density functional theory (DFT) was applied for calculating their geometries and frontier molecular orbitals. Their electroluminescence ability was examined in guest-host diode with structure ITO/PEDOT:PSS/PVK:PBD:imine / Al and emission of light with maximum of emission band from 626 to 674 nm was observed. This work demonstrates, to the best of our knowledge, the first example of light emitting devices based on thiophene azomethines as active layer component.
Current trends in the field of neural tissue engineering include the design of advanced biomateri... more Current trends in the field of neural tissue engineering include the design of advanced biomaterials combining excellent electrochemical performance with versatile biological characteristics. The purpose of this work was to develop an antibacterial and neuroprotective coating based on a conducting polymer - poly(3,4-ethylenedioxypyrrole) (PEDOP), loaded with an antibiotic agent - tetracycline (Tc). Employing an electrochemical technique to immobilize Tc within a growing polymer matrix allowed to fabricate robust PEDOP/Tc coatings with a high charge storage capacity (63.65 ± 6.05 mC/cm2), drug release efficiency (629.4 µg/cm2 ± 62.7 µg/cm2), and low charge transfer resistance (2.4 ± 0.1 kΩ), able to deliver a stable electrical signal. PEDOP/Tc were found to exhibit strong antimicrobial effects against Gram-negative bacteria Escherichia coli, expressed through negligible adhesion, reduction in viability, and a characteristic elongation of bacterial cells. Cytocompatibility and neuroprotective effects were evaluated using a rat neuroblastoma B35 cell line, and were analyzed using MTT, cell cycle, and Annexin-V apoptosis assays. The presence of Tc was found to enhance neural cell viability and neurite outgrowth. The results confirmed that PEDOP/Tc can serve as an efficient neural electrode coating able to enhance charge transfer, as well as to exhibit bifunctional biological characteristics, different for eukaryotic and prokaryotic cells.
Novel dyes based on the phenothiazine system D/A–π–D–π–A exhibit that elongation of π-conjugation... more Novel dyes based on the phenothiazine system D/A–π–D–π–A exhibit that elongation of π-conjugation is advantageous in the design of efficient photosensitizers.
In this work novel bisheterocyclic derivatives of alkylcarbazole with A–CZ–A architecture are inv... more In this work novel bisheterocyclic derivatives of alkylcarbazole with A–CZ–A architecture are investigated (CZ stands for alkylcarbazole). The study presents their opto-electronic and electrochemical properties which influence on the possibility of their prospective application. Monomers undergo electropolymerisation with formation of conducting layer of polythiophene derivatives, while presence of chalcone moiety hampers the process. Two-step oxidation processes of polymers results in generation of polaron and bipolaron types of charge carriers on the macromoleculs’ chains. The charge is delocalized over center and side subunits (bithiophene or bithiazole one) in first stage of oxidation. It is possible to influence on the properties of the polymers and their composition by variation of synthesis condition like solvent polarity and applied potential boundaries. Obtained conducting polymers show high stability under ambient conditions. Their energy gap values are estimated with electrochemical and spectroscopic methods.
Abstract In this work we report the synthesis, electrochemical and optical properties of five new... more Abstract In this work we report the synthesis, electrochemical and optical properties of five new, star shaped compounds containing both carbazole and triphenylamine moieties, further endcapped with thiophene or 3,4-ethylenedioxythiophene units. Electrochemical, UV–visible spectroscopy and fluorescence methods were employed to study the properties of these compounds as well as their electropolymers. The basic characteristics such as the band gaps, HOMO and LUMO values, absorption and emission maximum wavelengths of the monomers and the polymers are reported and discussed.
Uploads
Papers by Sylwia Golba