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Öğe Biological Activity and Optical Sensor Properties of Green Synthesis Polymer(Wiley-V C H Verlag Gmbh, 2022) Bahceci, Dilek Senol; Demir, Neslihan; Kocaeren, Aysel AydinIn this study, 4-amino-3-hydroxy-1-naphthalene sulfonic acid (Monomer) was converted to its enzyme-catalyzed oxidative polymerization (Poly-enz) in dioxane solvent by horseradish peroxidase enzyme (HRP) in the presence of hydrogen peroxide as oxidant. For the analysis of the monomer and its synthesized Poly-enz, H-1-NMR, C-13-NMR, FT-IR, TGA, and SEM measurements were determined. In addition, the optical ion sensor properties of Poly-enz against metals such as Ag+, Cd2+, Co2+, Hg2+, Ni2+, Pb2+, Zn2+, Cu2+ were examined with UV-Vis spectrophotometer. It was observed that Cu metal showed sensory properties. DNA cleavage and DNA binding activities of monomer and Poly-enz were done using by agarose gel electrophoresis and UV-Vis methods, respectively. It was seen that the Poly-enz interacted with DNA electrostatically. This enzymatic polymer was found to cleave pBR322 plasmid DNA both hydrolytically and oxidatively as well. The antioxidant activities of the compounds were examined by three different methods (DPPH, ABTS, FRAP) and it was found that the Poly-enz showed high antioxidant activity compared to its monomer. Antimicrobial activities were studied against various bacterial and yeast cultures by the minimum inhibition concentration (MIC) method. It was observed that the antimicrobial activities of the enzymatic polymer in different microorganisms increased depending on the concentration.Öğe Electrochemical Fe3+ Ion Sensor Applications on Different Electrode Surfaces(Maik Nauka/Interperiodica/Springer, 2023) Kocaeren, Aysel AydinThe carbazole compound (C-C-8) containing aromatic ring with 8 carbon alkyl group (C8) was synthesized. The thiophene-derived compound that was abbreviated as (T) was synthesized, and (CT-C-8) was obtained by adding of (T) to the starting compound (C-C-8). Additionally, the electrochemical polymers of CT-C-8 were synthesized and accumulated onto different surface types such as an indium tin oxide (ITO) coated glass, aluminum (Al) layer, copper (Cu) sheet and pen tip electrode (PTE). The electrochemical syntheses of the polymers were performed by using 0.05 M NaClO4 as an electrolyte in acetonitrile (AN) solvent. The electrochemical behaviors of the polymers were also investigated by taking the cyclic voltammeric measurements with a triple electrode system, and the electrochemical behaviors of the coated polymers on different electrode surfaces were also researched in the presence of Fe3+ and Fe(2+ )metals. According to the obtained voltammogram results, it can be said that the electrochemically synthesized polymers on different electrode surfaces were sensitive to Fe3+ metal and they could be used as an electrochemical sensor for all electrode surfaces as mentioned above. For the performed electrochemical measurements, the oxidation and reduction peak values obtained for different electrode surfaces were different from each other. When it is desired to examine the electrochemical property of a material, there is a need to search for more useful and economical insoles, since the conductive surface like ITO is deformed after repeated applications and expensive. This study, which offers an alternative conductive base to replace ITO, is important in this regard.Öğe Electrochemical polymer synthesis using thiophene and pyrrole/carbazole: Their electrochemical behaviours and capacitor performance(Elsevier Science Sa, 2024) Kocaeren, Aysel Aydin; Bahceci, Dilek Senol; Kizilkaya, Bayram; Dogan, FatihIn this study, carbazole-derived monomers were synthesized on ITO-coated PET via electrochemical reactions and conductivity measurements of the resulting polymeric films were performed by UV, FT-IR, NMR, TG-DTG, SEM and AFM analyses. Their spectroelectrochemical properties were investigated. The carbazole (C) based thiophene (Th) polymer abbreviated as pThC and its copolymer with pyrrole (Py), named as pThC-Py were obtained by electrochemical polymerization method. The surface stability of the resulting polymer films was good depending on time. The contact angle (CA) between the water and theco- polymer surface was determined by dropping 6.09 mu L of pure water and CA average was calculated as 68.19 degrees < 90 degrees. According to the thermal analysis data of the polymers, the thermal stability of the pThC-Py was better than pThC as it had higher thermal decomposition temperature. Comparisons of electrical conductivity measurements of the polymer films were made depending on the temperature (25, 50 and 90 degrees C). Due to increasing temperature, the electrical conductivity of pThC-Py film was read as 29.3 S/cm at 90 degrees C, and also the electrical conductivity values of the pThC-Py were determined as 1.92 x 10(-2) S/cm at 25 degrees C and 14.2 S/cm at 50 degrees C. Because of the high electrical conductivity of the pThC-Py, its capacitor performance was tried to be determined from cyclic voltammetric measurements. According to the voltammetric results, the power density (P) and the energy density (E) values of the synthesized substance were calculated as 290.532 W/g and 9.684 Wh/g, respectively. This indicates that the amount of energy the material storable is relatively high. Moreover, it is possible to say that it can be included in the classical capacitor class and in the supercapacitor category by improving its features. Moreover, since the electrical conductivity of pThC-Py is quite good, it is thought that it may be suitable for use in electronic devices.Öğe Investigation of Permeability Against Some Metals with a Functional Thiophene Based Polymeric Membrane Sensor(Wiley-V C H Verlag Gmbh, 2024) Kocaeren, Aysel Aydin; Karakurt, EmineThere are many advantages of using membranes in the separation of wastewater, but their uses are limited because they are not reusable due to blockages in the membrane. In this study, alginate-based poly(ethyl-methacrylate) (PEMA) polymeric membranes containing previously synthesized IOS, which are known to be selective against Fe3+, were prepared and their permeability against heavy metals such as Cd2+, Co2+, Cu2+, Fe3+, Hg2+ and Pb2+ were investigated. The properties of membranes characterized by UV-Vis and FT-IR spectrophotometry, were investigated with analysis techniques such as SEM, contact angle measurements, TG-DTG, DSC and AFM. As a result of the measurements taken from the UV spectrophotometer of the filtrates passed through various aqueous ion solutions of the membranes as mentioned above, it was concluded that the ion to which the membrane was most selective was the Fe3+ ion. Moreover, it could be said that thanks to the repeated filtration processes the membrane prepared retained some Fe3+ ion in each measurement and could be used many times in the filtration process. Resultantly, it is possible to say that the polymeric Fe3+ membrane sensor produced may be suitable for use when it is necessary to remove Fe3+ ion from a polluted aqueous environment.Öğe Optical Sensor Applications of Carbazole Derivative Polymers Containing Different Aliphatic Groups Against Fe3+ Metal Ion(Maik Nauka/Interperiodica/Springer, 2022) Kocaeren, Aysel Aydin; Bahceci, Dilek Senol; Dogan, FatihThe carbazole derivatives containing aromatic rings with long alkyl groups such as C-6, C-8, C-10 and 3,4-bis(4-iodophenoxy) thiophene are synthesized. The products of carbazole derivatives and 3,4-bis(4-iodophenoxy) thiophene interaction were polymerized using FeCl3 oxidant. The structural characteristics of the synthesized compounds were obtained by FT-IR and NMR spectroscopy. UV measurements are performed to determine the optical changes of the copolymers in the presence of metal ions such as Ag+, Cd2+, Co2+, Cu2+, Fe2+, Fe3+, Hg2+, Li+, Ni2+, Pb2+, Zn2+. The selectivity of Fe3+ is investigated by recording of the absorbance changes of Fe3+ solutions prepared at different concentrations. The effect of pH is also investigated in optical sensor studies. According to UV measurements, the materials containing thiophene and carbazole units can be considered as candidates for sensor production due to their selectivity towards Fe3+ ions.Öğe Surface properties and electrochemical synthesis of carbazole derivative polymers(Springer Int Publ Ag, 2024) Kocaeren, Aysel Aydin; Uzun, BeyzaIn this study, carbazole-derived polymers were synthesized on ITO (indium tin oxide)-coated PET (Polyethylene terephthalate) via electrochemical reactions and conductivity measurements of the resulting polymeric films depending on temperature were actualized via four-point probe system. Their characterization processes were carried out by UV, FT-IR, NMR, TG-DTG, SEM analyses. Spectroelectrochemical measurements were performed for investigating their electrohromic properties. Homopolymer (P-6C) of carbazole-derived monomer as well as copolymer with thiophene were obtained by electrochemical polymerization method. Based on the CV measurements taken, the resulting copolymer film had good stability on the electrode surface. According to the thermal analysis of the homopolymer, its final degradation temperature was 297 degrees C and its residue amount at 800 degrees C was calculated as 18%. Comparisons of conductivity measurements were made depending on the temperature of the polymer films (25, 50 and 90 degrees C). The electrical conductivity values of the thiophene-carbazole derivative copolymer (6C-T) were decreased depending on the temperature (13.7 S/cm at 25 degrees C, 1.99 x 10-2 S/cm at 90 degrees C). The conductivity of carbazole derivative homopolymer product (P-6C) was recorded to increase 10 times with increasing temperature. In the SEM image of P-6C a large and small, non-homogeneous surface with rounded corners was observed. Also, in the SEM image of the copolymer with thiophene (6C-T), small structures with rounded corners originating from thiophene and a non-homogeneous flat surface were seen. As a result, it has been revealed that the copolymer obtained from thiophene and carbazole derivatived compound could be used as a component in electronic devices due to its high conductivity value.Öğe Synthesis, characterization of polymeric ligand-metal complexes and their biological activity properties(Elsevier, 2023) Kocaeren, Aysel Aydin; Bahceci, Dilek Senol; Demir, Neslihan; Dalgic, Busra; Karatag, ElifnurNew members are joining to the Schiff bases family every day. In our study, firstly a new Schiff base was abbreviated as ligand (L) that was synthesized via condensation reaction between 3-aminonaphtalen-2-ol and 2,3-dihydroxybenzaldaheyde. Then, poly-ligand (PL) was obtained in basic medium in the presence of ammonium persulfate (NH4)2S2O8 via poly-condensation reaction by using L. Metal complexes were synthesized from the interaction of PL with various metal species such as Zn2+, Hg2+, Ni2+, Pb2+and Cu2+. The structures of compounds were confirmed by FT-IR, UV-Vis, 1HNMR and elemental analysis. Their SEM images were recorded at different sizes. Looking at the SEM images, it can be seen that the [Hg(PL)2] metal complex is similar to the red blood cells. Thermal analyses of PL and its metal complexes [M(PL)2] were performed. The biological properties such as DNA binding-cleavage, antioxidant and antibacterial activities of all synthesized compounds were investigated. According to the results, it was determined that such properties of its metal complexes were better than PL. For example, when the oxidative cleavage activity was examined, it was determined that [Cu(PL)2] complex completely cleaved the DNA and also it denatured all DNA at higher concentrations (& GE;100 ppm). DNA binding for the poly-ligand and its metal complexes bounded to CT-DNA in electrostatic mode. The antioxidant activity results showed that [Hg(PL)2] complex had a high inhibition value of 78.70 & PLUSMN;0.55% at 100 ppm. The [Hg (PL)2] complex was much more effective against all bacterial strains. The antibacterial activity of [Cu(PL)2] and [Zn(PL)2] complexes showed the highest activity against B. subtilis strain at the concentration of 62.5 & mu;g/mL. DNA binding was determined from the UV-Vis spectra of the interaction of the PL and its metal complexes with CT-DNA. According to these UV-Vis results, it can be said that the poly-ligand and its metal complexes bounds to CT-DNA in electrostatic mode.Öğe Thiophene-containing Schiff base polymers: synthesis, characterization, and anti-bacterial properties(Springer, 2023) Kocaeren, Aysel Aydin; Karatag, ElifnurWe synthesized the Schiff bases and their polymers, which contain thiophene units. For the synthesis process, first, hydroxynaphthalene di- and triol-derived Schiff bases that are abbreviated as (A1) and (A2) were prepared by a common condensation reaction. Second, their polymers named as B1 and B2 were separately synthesized from the oxidative polycondensation of the Schiff base monomers with (NH4)(2)S2O8 in an aqueous alkaline medium. The new polymeric structures that are abbreviated as B1-S and B2-S, containing thiophene groups, were synthesized by HBr elimination using B1 and B2 polymers. The characterization processes of the synthesized products were carried out using spectroscopic techniques such as FTIR, UV-Vis, H-1 and C-13 NMR, TG-DTG analysis, and MALDI-TOF MS. According to the TG analysis results, except for A2, the thermal stabilities of the other compounds were good since they left about 50% residue at 800 degrees C. SEM images of the compounds were recorded at different sizes, and also they were found to be quite different from each other. For example, A1 was like a ball. Additionally, A1, A2, B1, B2, B1-S, and B2-S were tested for their anti-bacterial activities against some bacteria types. Minimum inhibitory concentration (MIC) method was used for the anti-bacterial activity tests. The MIC test results showed that the synthesized polymers could be used as antimicrobial agents for surfaces with P. vulgaris NRRLB-123 bacteria at lower concentrations such as 15.625 and 31.25 mu g/mL. [GRAPHICS] .
