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    Electrochemical polymerization of 2-aminothiazole
    (Springer, 2011) Ciftci, Hakan; Testereci, Hasan Nur; Oktem, Zeki
    Electrochemical polymerization of 2-aminothiazole (AT) was studied in acetonitrile with tetrabutylammonium tetrafluoroborate (TBAFB) as the supporting electrolyte via constant potential electrolysis (CPE). The redox behavior of AT was investigated in the same solvent-electrolyte couple by cyclic voltammetry, CV. CPE of AT produced a soluble conducting polymer on the electrode surface. The effects of temperature, monomer concentration and polymerization time on the rate of electrochemical polymerization were also studied. The structural analyses of the polymer were carried out by H-1-NMR, FTIR and UV-VIS spectroscopies and elemental analysis. Thermal properties were studied by DSC and TGA. Conductivity measurements were carried out by four-probe technique and the number average molecular weight, M (n), of the polymer was determined by cryoscopy.
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    High iron content of Ankaferd hemostat as a clue for its hemostatic action of red blood cell origin
    (Lippincott Williams & Wilkins, 2015) Akar, Nejat; Ardicoglu, Yasemin; Oktem, Zeki; Erduran, Nuran; Haznedaroglu, Ibrahim C.
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    Polymers from renewable resources: synthesis and characterization of poly(2,5-dihydro-2,5-dimethoxy furan)
    (Scientific Technical Research Council Turkey-Tubitak, 2012) Ciftci, Hakan; Oktem, Zeki; Testereci, Hasan Nur
    The cationic polymerization of cis, trans-2,5-dihydro-2,5-dimethoxy furan (DHMF) was studied in the presence of HClO4, in acetonitrile. Different reaction parameters were investigated such as initiator concentration and temperature with duration. Obtained polymers were soluble in dimethylsulfoxide (DMSO) and dimethylformamide (DMF) and the M-n value was calculated as 2700 g/mol by cryoscopy. The FT-IR and H-1-NMR results indicate that the polymerization proceeds via ring opening. Thermal properties were studied by DSC and TGA.
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    Preconcentration and electroanalysis of copper at glassy carbon electrode modified with poly(2-aminothiazole)
    (Gazi Univ, 2011) Ciftci, Hakan; Testereci, H. Nur; Oktem, Zeki
    Conducting poly(2-aminothiazole), PAT, was synthesized in acetonitrile with tetrabutylammonium tetrafluoroborate, TBAFB, as supporting electrolyte via constant potential electrolysis, CPE. Glassy carbon, GC, electrode was modified by immersing the electrode in a DMSO solution of PAT. Preconcentration of copper on polymer matrix was carried out at -0.7 V. The effects of preconcentration time and pH and Cu(II) concentration of the preconcentration solution on the stripping peak current of copper were studied.
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    Preconcentration and electroanalysis of silver at pt electrode modified with poly(2-aminothiazole)
    (Maik Nauka/Interperiodica/Springer, 2013) Ciftci, Hakan; Testereci, Hasan Nur; Oktem, Zeki
    Conducting poly(2-aminothiazole) (PAT) films were electrodeposited on a platinum disc electrode surface by constant potential electrolysis of 2-aminothiazole (AT) for the stripping voltammetric determination of Ag(I). Ag(I) was preconcentrated on the polymer matrix by dipping the modified Pt electrode (PAT-Pt electrode) into Ag(I)(aq) solution. Effects of the film thickness, reduction potential, pH, preconcentration time, Ag(I) concentration and the interference of some other metal ions on the oxidation peak current of silver were studied. Cu(II) interference observed to be significant for the stripping voltammetric determination of Ag(I). The detection limit was calculated on the basis of signal to noise ratio of 3 as 2 x 10(-7) mol L-1.
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    Ring opening polymerization of 2-aminothiazole with iron(III) chloride
    (Springer, 2013) Ciftci, Hakan; Testereci, Hasan Nur; Oktem, Zeki
    Poly(2-aminothiazole), PAT, was synthesized by the chemical polymerization of 2-aminothiazole, AT, with FeCl3 center dot 6H(2)O in 1,4-dioxane. The effect of temperature, monomer, and initiator concentration and polymerization time on the rate of polymerization was studied. The structural analysis of the polymer was carried out by elemental analysis and H-1-NMR, FTIR, and UV-VIS spectroscopies. Thermal properties were studied by DSC and TGA. Conductivity measurements were carried out by four-probe technique and the number average molecular weight, M (n), of the polymer was determined by cryoscopy.
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    Voltammetric determination of Hg(II) at poly(2-aminothiazole) modified platinum electrode.
    (Parlar Scientific Publications (P S P), 2011) Ciftci, Hakan; Oktem, Zeki
    Conducting poly(2-aminothiazole) (PAT) film was electrodeposited on platinum disc electrode surface by cyclic voltammetry of 2-aminothiazole (AT) for stripping voltammetric determination of Hg(II). Hg(II) was pre-concentrated on to polymer matrix by adsorption upon dipping the modified electrode into Hg(II) solution. The effect of electrolysis time, number of electropolymerization cycles, pH, preconcentration time and Hg(II) concentration on the determination of Hg(II) were studied. A linear relation between the peak current and Hg(II) concentration was obtained in the range of 0.1-1.1 mg L-1. The relative standard deviation was calculated as 1.37% at 0.5 mg L-1 Hg(II) (n=6). The detection limit was estimated as 0.025 mg L-1 by means of 3:1 current-to-noise ratio. The interferences of Ni(II), Cu(II), Pb(II), Zn(II), Cd(II) and Fe(III) were investigated in the determination of Hg(II). The optimized method was successfully applied to the determination of Hg(II) in the River Kizilirmak samples by means of standard addition method.