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    Electrochemical behaviour of acrylamide polymers functionalized with some schiff bases
    (Gazi Univ, 2011) Deletioglu, Didem; Hasdemir, Erdogan; Solak, Ali Osman; Sari, Nursen
    CV, SWV and CA have been used to investigate the electrochemical behaviour of 2-hydroxy-5bromobenzaldehyde polyacrylamide (PABSB), 2-hydroxy-5-chlorobenzaldehyde polyacrylamide (PACSB) and 2-hydroxy-5-methylbenzaldehyde polyacrylamide (PAMSB) at the mercury electrode in aqueous media. The bromo-and chloro-derivatives were electroative while the halide-free compound, the methyl-derivative, was not. The analysis of the experimental data supports the formation of anion radicals as a result of C-X bond cleavage. Following the electron transfer step, a protonation reaction was thought to be occuring through the EirrC mechanism. The large polymeric molecules are adsorbed at the mercury electrode as expected contributing the adsorption current component to the diffusion one.
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    Preparation and characterization of poly(indole-3-carboxaldehyde) film at the glassy carbon surface
    (Elsevier Science Sa, 2010) Deletioglu, Didem; Hasdemir, Erdogan; Solak, Ali Osman; Ustundag, Zafer; Guzel, Remziye
    Indole-3-carboxaldehyde (In3C) monomer was oxidized by electrochemical methods at the glassy carbon (GC) electrode in 0 05 M tetrabutylammonium tetrafluoroborate in acetonitrile with the aim to prepare a modified electrode Modification was performed using cyclic voltammetry (CV) scanning from 0 0 V to 2 0 V at a scan rate of 50 mV s(-1) for 10 cycles in 1 mM In3C monomer solution The modified GC surface (In3C-GC) was characterized by CV response of potassium ferricyanide and ferrocene redox probes as well as by the electrochemical impedance spectroscopy The modified surface was analyzed by reflection-absorption infrared spectroscopy and compared with the spectrum of the monomeric In3C Elemental composition of the surface was determined by X-ray photoelectron spectroscopy Contact angle measurements was also performed to check the changes in hydrophobic character of the bare GC and compared to that of In3C-GC surface Thickness of the oligomeric/polymeric film was investigated by ellipsometric measurements and a surface confined polymerization mechanism was proposed (c) 2010 Published by Elsevier B V
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    Simultaneous Determination of Dopamine and Uric Acid in the Presence of Ascorbic Acid at the Indole-3-Carboxaldehyde Modified Glassy Carbon Electrode
    (Bentham Science Publ Ltd, 2010) Deletioglu, Didem; Hasdemir, Erdogan; Solak, Ali O.
    Indole-3-carboxaldehyde (In3C) molecules were deposited on the glassy carbon (GC) electrode by electrochemical methods in acetonitrile (containing 0.05 M TBATFB). Deposition of In3C was performed by cyclic voltammetry scanning from 0.0 V to 2.0 V at a scan rate of 50 mV s(-1) for 10 cycles in 1 mM In3C solution. The modified surface (In3C-GC) was characterized by cyclic voltammetric response of ferrocene as a redox probe. Elemental composition of the surface was analyzed by X-ray photoelectron spectroscopy (XPS). The applicability of this modified surface was then investigated for the determination of dopamine (DA) and uric acid (UA) in the presence of ascorbic acid (AA) using differential pulse voltammetry. Detection limits were calculated as 1.70 mu M for DA and 4.99 mu M for UA. The linear ranges of the calibration curves were found between 10 mu M -100 mu M for both DA and UA in the presence of 100 mu M AA. The proposed method was applied to the determination of DA and UA in pharmaceutical preparations and urine samples with satisfactory results.